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Overseas Jack Rebuild Help Tutorial.

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Hiball

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HiBall: THANK YOU THANK YOU THANK YOU !!!! your tutorial helped me figure out that all that was wrong with my 1991 vintage Sears 2 1/4 TON floor jack, was the "back-off" of the overload....(or maybe just "junk" in the fluid, not sure....but after taking it apart, draining all the fluid, and figuring out WHERE the 2 (small and bigger) ball bearing went, then new jack oil, that fixed it !!! little went in 1st, then the larger one, under the hex-head bolt...

model # 9-50110 or 214-501100 ??
works like new, now !!!

It has worked well, just occasional-shade-tree use, until the last few weeks....I had bought it new in '91 or '92

Really needed that jack, and did NOT look forward to buying a new (very-likely-inferiorly-made-one) !!!!

Sincerely, Jim Jensen St. Augustine, FL

Glad everything worked out.. Remember to use jack stands and only use the jack for lifting the load.
 
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Jimmer4590

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I have two imported floor jacks, that I would like to rebuild. One is a Craftsman 3 ton model # 875.501390 it leaks, and does not fully lift. The other is also a 3 ton, I don't know who made it, its model # 45426. I hope by the photos someone can identify it. My hope is that someone can recommend a place to buy the correct seal kits for these jacks. Thanks
 

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EDGAR

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Both jacks use the same Torin pump. Should be basically the same parts in both jacks, although there have been some variations over time in these pumps. These pumps are the same pump presented at the beginning of this tutorial.

As far as o-rings, these will have to be sourced in your local hydraulic store or online. The only company selling kits for these jacks is OTC. They have a model OTC 1503A and OTC 1504A which use these pumps. But, as I mentioned above , there are some variations on the pumps, so these kits may or may not have the same parts as your jacks.

Below see a parts breakdown for the OTC jack.

http://www2.otctools.com/otctools.com/newcatalog/products/522982_E.pdf
 

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jacked_72

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I've got two Shinn Fu jacks that I recently picked up. One was a 1988 Sears and the second was a MVP Superlift G-630MW. I got them both working without need of replacing the cup seals that they both have, but I contacted Shinn Fu USA in the process of reworking them looking for seal kits. I was told that on the Sears jack that they don't carry parts for anything that old and on the Superlift (which is probably only 5-8 years old) that they don't have seal kits for anything sold in retail stores. Luckily, I don't need either seal kit as it turns out, but I just wanted to let people who have Shinn Fu jacks (which sounds like a lot of people since they rebrand a ton of jacks) know that the chances of getting seals from the manufacturer are slim.

I don't know that anyone would care, but I took a couple of pictures of the main cup seal in the Superlift, wich is a quick raise jack. The Sears model had a similar cup seal, but I didn't measure it.
 

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65GoatMan

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Your tutorial looks helpful and I am going to attempt to repair a floor jack I paid $225 for just five years ago that has leaked all over my garage floor twice.
It's a Mac One Pump to Load 3 1/2 ton (JSA350MA) Chinese pile of junk.

I have to admit the Mac Tool salesman came to my house, picked up the leaking jack, got is supposedly repaired, only to have it leak on my floor about a year later.

I contacted Mac and purchased a seal kit for $19. If I had not have paid so much for this jack I probably would have chucked it and bought a $60 jack from Sam's Club. It's likely the same jack painted a different color without the Mac Tools sticker.

My question is if there is anything I can check to determine the cause of the leak before taking this jack apart and re-sealing it. I suspect that I will end up rebuilding it. Also, is there anything unique to look out for while rebuilding a one-pump floor jack?

Thanks for your time.
 

HCRCnow

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To find out what part is leaking. Clean the jack, fill it again with fluid, jack it up, then find a clean place and a clean piece of cardboard. Put the jack on top of the cardboard, then wait over night. Then hunt down the leak. Look at the places the drips are on the cardboard.
 
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Hiball

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To find out what part is leaking. Clean the jack, fill it again with fluid, jack it up, then find a clean place and a clean piece of cardboard. Put the jack on top of the cardboard, then wait over night. Then hunt down the leak. Look at the places the drips are on the cardboard.

I would like to add, make sure you fully inspect the underneath.. I've witnessed oil seep from the pump piston and run underneath the jack and fall off at the opposite end. Hydraulic oil is crazy like that... LOL
 

Alexbn921

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Hi
Thanks to Hiball I decided to tear apart my 4 year old Craftsman 2 ton aluminum jack. It started leaking right away and then would not lift to full height. I have not used it in 2 years and finally decided to tear it apart. Nothing to lose at this point.


Pulled out the ram unit. It was only held in by a couple bolts and a pin.

Pump piston was leaking so off it came.


I replaced all the O-rings and cleaned everything. I laid out all the parts so I won’t miss anything.


I DID MISS SOMETHING.
This morning I found a small ball bearing on the floor this morning. Any Idea where it goes?
I’m thinking it goes all the way to the right side. It’s the only one without a ball. Other than that it seems to work fine and doesn’t leak at all.
 
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Hiball

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Hi
This morning I found a small ball bearing on the floor this morning. Any Idea where it goes?
I’m thinking it goes all the way to the right side. It’s the only one without a ball. Other than that it seems to work fine and doesn’t leak at all.

The far right valve is the Quick Lift Valve, Some of those valves did utilize a Upper and Lower seat. If you look down in the Valve bore how many seats do you see? What does the tip of that Cone piece look like? Does it have a Upper seat? It doesn't appear to be pointy, Size of the Ball?.
 

crackedback

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Oct 9, 2012
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Great thread!

I have this same sears jack pictured below, purchased in the late 70's, early 80's is my guess. It's decided to not hold pressure. Pump and arm rises then falls right away with no weight applied.

I tried like crazy to get the can off. No dice, need a better wrench cheater bar.

The port with the screwhead is peened on both sides. Not sure on a good approach to get that removed.

 

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Hiball

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Great thread!

I have this same sears jack pictured below, purchased in the late 70's, early 80's is my guess. It's decided to not hold pressure. Pump and arm rises then falls right away with no weight applied.

I tried like crazy to get the can off. No dice, need a better wrench cheater bar.

The port with the screwhead is peened on both sides. Not sure on a good approach to get that removed.


A good hand impact will make quick work of those peen dots.
 

EDGAR

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Since the jack is so old, there is a high probability of a broken u-cup seal. You should try to remove the big nut just to check before proceeding with the peened cap, although if the u-cup is broken, depending on the size of the broken pieces you may need to flush the pump to remove any small cup piece that can later jam the working valves. Flushing the pump requires the removal of all caps.

Urethane u-cups keep breaking into smaller pieces more and more over time, so sometimes one can find in the cylinder just little pieces of u-cup that look more like coarse gravel than a seal. If the break was recently, you will find maybe a couple of breaks at most. And even if by chance, the u-cup is not broken, it should be changed for a new one as u-cups, in general, don't last as long as yours has.

Just remember to make a mark on the big nut so when mounting it back, you can take it back to the position it was when assembled at the factory. This more or less, would be close to the torque applied at the factory to this part. The easiest way of removing the big nut is by using a 18" pipe wrench with a five feet pipe as a cheater bar.
 
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crackedback

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Ram and seal. It was cracked and dried out very badly.





I have a neighbor at a hyd shop that busted the tank loose. Nice to have giant socket and a industrial sized air gun. He suggested that I not mess with the peened cover. I may not listen... LOL He doesn't deal with these anymore or have any of the metric seals. His comment was to use it as a boat anchor. :)

There were a lot of pieces and some gritty residue, so it needs a good flush.
 
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Hiball

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PM Responded too Crackedback.

And Don't fret over that Peened Cover, Its not Brain Surgery, Underneath that cover is simply the Working Valve. Id also say your Jack is worthy of a Rebuild, As you can see it uses a Real Ucup and based off the Service its already provided you owe that Jack. LOL.. If you search GJ you will only find Good time stories about those Old Green and White sears jacks, its not a uncommon theme to hear stories of 20+ years of service, Mainly because they do utilize a such a Hefty Ucup.
 
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crackedback

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It really died about 5 years ago, just sitting in the corner in time out since then! I have a bleeding china freight one too... that will be next.

I'd love to get this old sears dog up and running again.

Thanks again for taking the time to cover this stuff, help out and give guidance. :thumbup:
 

noquarter

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Jun 9, 2012
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This has got to be one of the most epic posts of all time! Hello all. I'm a long-time lurker, but I wanted to pitch in one little bit of advice that might help some of you. I have one of those Sears 2 Ton Japanese Jacks model 328.12160. I found it on Craigslist for $10 and figured I'd just dive in and try to fix it. The how-to here shows an allen screw that you remove next to the twist valve that you twist to lower the jack, etc. Mine has a slotted screw with about a 1/16" slot 3/4" long. I called NAPA looking for a drag link socket that would fit. Nothing doing. I was trying to figure out how I could make a tool to remove this screw and do it cheap. I needed a hardened piece of steel about that size but what would work? Well I work at a hardware store and found this tool made by Vaughan. Look at this: http://www.doitbest.com/Nail+pullers-Vaughan+Bushnell-model-222-doitbest-sku-356670.dib

It's a mini-bar for pulling tack nails. I bought it, took a flap disc and put it in my angle grinder and ground the tapered end flat (the short end and not the long end.) Using a hammer, I tapped it into the slot and it fit nice and snug. With nothing but my bare hands, I was able to break this slotted bolt loose.

It's a pretty cheap tool you can buy and modify and it worked really well for me.

Enjoy my 2 cents. :)

NoQuarter
 
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noquarter

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Well thanks to Hiball, another jack has been rebuilt. Only having stumbled across Hiball's posts earlier in the week and using them for motivation, I bought a 2 Ton Sears floor jack on Craigslist for $10. It would pump up without a load but the minute a load was put on it, nothing worked. I ordered a seal kit from a shop in Long Beach, CA (and the $55 price tag is because you're paying for the time and research it took to throw $8 worth of seals in a bag and ship them out - and I'm okay with that because I don't have time to wait for the local places to order all the seals I need.) and it showed up yesterday. Earlier in the week I had removed the cylinder from the jack. This afternoon I finished disassembling the jack innards, cleaning, resealing, and reassembling the jack. When I went to the local O'Reilly Auto Parts to buy a quart of jack oil, they told me there was a 3 ton jack in the dumpster out back I could have if I was willing to fetch it out (more on that later.) I had enough foresight to chuck the caster wheels in a bucket of 20w-50 oil earlier in the week and then let 'em drip dry into a bucket of sawdust. I greased the stationary wheels and rolled the completed jack under the trailer hitch of the 2005 F150 delivery truck. It lifted the truck like it wasn't even there! A tip of the hat to Hiball for giving me the confidence to turn my $10 floor jack into a usable quality piece of shop equipment. I never did find out why the old jack wouldn't pump and hold before. All the seals looked good, however I do suspect the main lifting seal had shrunk and was allowing hydraulic fluid to simply go around it.

The rest of the story on that 3 ton dumpster jack - when I found it, it was in a plastic case and I didn't see the fresh red paint all over the one side of the case so now I have a nice wide red stripe across my overalls and my jacket. This is one of them smaller jacks you can throw behind the seat of a pick-up. Still it's beefy and rated at 3 ton. The pumping pin is sheared off for some reason (it was stuck the guys told me) so I'll dig into it and see if it can be fixed. :)

I'm a happy camper and sorry for the wordy post. I'm just happy to have fixed me a nice jack to use and got a free one to fix up to boot. If the ladies don't find ya handsome, at least they can find ya handy. :)

NQ
 
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noquarter

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Thanks for the kudos there Hiball. I'm asking the forum for help on where to locate parts for this jack. http://www.oreillyauto.com/site/c/d...N0768_-1_2385&keyword=jack&pt=N0768&ppt=C0373

It's an ACDelco 34119 and I can only assume that there is some main jack builder that slaps other people's names on this jack and sells them. The trick is going to find who makes them. One of the google search results listed a pdf of a Gardner Bender JH15, but it doesn't look quite right. I'm looking for a parts breakdown so I can order replacement parts. Thanks!

NQ
 
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EDGAR

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You did not mention what is wrong with your jack. Is it leaking oil from the ram? Is it leaking oil from the pump piston? More often than not, the seal that goes first in this type of mini jacks is the one in the pump piston. When this happens, the pumping performance deteriorates, sometimes even up to the point of the pump piston not being able to draw oil from the oil tank. The most common sizes for these pump piston seals, assuming it is using only an O-ring as seal, are 2mm x 8mm for a 11mm diameter piston and 2mm x 9mm for a 12 mm piston. Of course, this can vary with the different manufacturers and the tonnage rating of the jack, as some even use 1.5 mm cross section O-rings and others use 2.5mm O-rings. In others, the o-ring is used as a rod seal (the o-ring is in a groove in the cylinder, not mounted on the piston) which calls for different sizes depending on application.

Older jacks used only an u-cup, later that was changed to a combination of an u-cup and an o-ring. Still later it was changed to only the o-ring since it is a bidirectional seal while the u-cup works better in one direction and was also cheaper to manufacture.

As for as finding a seal kit for this jack, or a parts breakdown, the chances are from slim to nil. You will have to take it apart and measure the seals and hope that you can get aftermarket substitutes online or at your local hydraulic shop. Depending on how old or new is you jack, the main seal can be an u-cup or an o-ring and o-ring retainer combination. It might be easier, and cheaper, to find an o-ring for this application than an u-cup.

Be aware that 1.5mm/1.6mm and 2.5mm O-rings can be substituted with 1/16" and 3/32" cross sections O-rings. Also, 3.5mm may be substituted with 1/8" O-rings. As for 2mm, these are harder to find in local hydraulic shops as many only want to carry inch O-rings. Harbor Freight has a small metric o-ring kit that has the 2mm size. The larger kit, in a blue box, has 1.78mm O-rings which may work, or leak, depending on the application. But find out what you need before buying.

Online, there is a site called "theoringstore" that carries a lot of sizes of O-rings and u-cups.

http://www.theoringstore.com/
 

noquarter

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Hello Edgar and thanks for your post! I have a follow-up for all of you.

I hit the trail hard and actually emailed O'Reilly Auto Parts and blatantly asked them where they get the jacks from. Surprise surprise they emailed me back, said they don't stock replacement parts, and that they get them from Test Rite Products Corp. I looked that company up and called their Arkansas number. Matt, who answered, said that some parts are available and to call a certain phone number. It's basically the same as www.americancustomerservice.com where you can find user manuals with basic parts breakdowns for various items. Among other things, they show an aluminum Goodyear racing jack which looks just like the small 1.5 ton Harbor Freight jack. The common theme that I'm noticing is that the hydraulic part of the jack is shown as one assembly and to try and track those parts would require back tracking to China and knowing how to speak Chinese.

For now, the problem seems to be that when you pump the jack, the main ram goes out and then if put a little pressure on it while lifting up on the handle to pump, it goes back in. All the seals look just fine. What had happened is that the piston that pumps was rusty and became lodged in the cylinder. The guys at O'Reillys managed to extract it, clean it up, install it, and then a piece that hooks piston pump to the handle broke. I can fabricate my own - that's not a problem. I did disassemble the entire hydraulic pump portion of the jack last night and cleaned it all up. The innards feature the o-ring in a cup method of sealing. The only thing I'm concerned about is that someone else was in the jack before me and I have no idea if they've left out any parts. Immediately below the piston that pumps fluid, is a round plate that looks like a thin washer with a square hole in it. Below that I can see a ball bearing that sits on a seat, but it's easily dislodged and rattles around when you shake the empty pump. I can't help but think there is some significance to the square-holed washer like another part is missing or supposed to be in there.

I'm tempted to go to O'Reillys and buy this jack, bring it home and take out the piston to see what is in there. Then once I've identified what is missing, look for replacements, and reassemble the jack and return it to get my money back. I hate doing that because it's taking advantage and not really a legimate use of the return policy. I'm so close to getting this old jack working again, but without diagrams and parts lists, it's extremely difficult.

I have a chainsaw chain I need to sharpen so I'm gonna go out to the shop and see if I can monkey with it some more. Thanks for any suggestions and help. It'd make my day to get this jack going again.

Erin
 
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Hiball

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Hello Edgar and thanks for your post! I have a follow-up for all of you.

I hit the trail hard and actually emailed O'Reilly Auto Parts and blatantly asked them where they get the jacks from. Surprise surprise they emailed me back, said they don't stock replacement parts, and that they get them from Test Rite Products Corp. I looked that company up and called their Arkansas number. Matt, who answered, said that some parts are available and to call a certain phone number. It's basically the same as www.americancustomerservice.com where you can find user manuals with basic parts breakdowns for various items. Among other things, they show an aluminum Goodyear racing jack which looks just like the small 1.5 ton Harbor Freight jack. The common theme that I'm noticing is that the hydraulic part of the jack is shown as one assembly and to try and track those parts would require back tracking to China and knowing how to speak Chinese.

For now, the problem seems to be that when you pump the jack, the main ram goes out and then if put a little pressure on it while lifting up on the handle to pump, it goes back in. All the seals look just fine. What had happened is that the piston that pumps was rusty and became lodged in the cylinder. The guys at O'Reillys managed to extract it, clean it up, install it, and then a piece that hooks piston pump to the handle broke. I can fabricate my own - that's not a problem. I did disassemble the entire hydraulic pump portion of the jack last night and cleaned it all up. The innards feature the o-ring in a cup method of sealing. The only thing I'm concerned about is that someone else was in the jack before me and I have no idea if they've left out any parts. Immediately below the piston that pumps fluid, is a round plate that looks like a thin washer with a square hole in it. Below that I can see a ball bearing that sits on a seat, but it's easily dislodged and rattles around when you shake the empty pump. I can't help but think there is some significance to the square-holed washer like another part is missing or supposed to be in there.

I'm tempted to go to O'Reillys and buy this jack, bring it home and take out the piston to see what is in there. Then once I've identified what is missing, look for replacements, and reassemble the jack and return it to get my money back. I hate doing that because it's taking advantage and not really a legimate use of the return policy. I'm so close to getting this old jack working again, but without diagrams and parts lists, it's extremely difficult.

I have a chainsaw chain I need to sharpen so I'm gonna go out to the shop and see if I can monkey with it some more. Thanks for any suggestions and help. It'd make my day to get this jack going again.

Erin

Some of those small trolley jacks did utilize a reservoir feed valve/ball in the actual Pump cylinder.

Does This Exploded view diagram mimic your jack?
 
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noquarter

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That's pretty much it Hiball. I had a nice reply typed to you and my login timed out and I lost it. BLAH! I gotta get in the habit of copying what I type before submitting it so if it bombs out I can just paste it back in the reply window.

The only thing I can figure out is that I couldn't remove #46 to verify if #38 was present. That's where that 2nd ball is hidden - couldn't seem to find it and I bet that's why pressure is feeding back into the pump cylinder. Mine is almost the same but it's just a straight shaft with no pumping cup on the end - yeah - really cheap. I'm missing #23 completely as well. It looks like there is some kind of metal plate in the bottom of the jack which must contain the ball bearing? The flap is not depicted in the diagram. Since I found the screen loose in the jack, I'm wondering if a piece lodged under #38 and is holding it open. Looks like another draining and tear down. I gotta try and get #46 removed - it was on there tight! Thanks for your help Hiball. I will keep you all posted.

I'm really enjoying this learning experience because I never really understood how jacks worked. Even though this AC Delco jack is disposable, it's really fun getting a mental grasp on what is going on. That mental process is what helps you diagnose problems. Understanding it is 9/10ths of the repair.

NQ
 
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Hiball

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That's pretty much it Hiball. I had a nice reply typed to you and my login timed out and I lost it. BLAH! I gotta get in the habit of copying what I type before submitting it so if it bombs out I can just paste it back in the reply window.

The only thing I can figure out is that I couldn't remove #46 to verify if #38 was present. That's where that 2nd ball is hidden - couldn't seem to find it and I bet that's why pressure is feeding back into the pump cylinder. Mine is almost the same but it's just a straight shaft with no pumping cup on the end - yeah - really cheap. I'm missing #23 completely as well. It looks like there is some kind of metal plate in the bottom of the jack which must contain the ball bearing? The flap is not depicted in the diagram. Since I found the screen loose in the jack, I'm wondering if a piece lodged under #38 and is holding it open. Looks like another draining and tear down. I gotta try and get #46 removed - it was on there tight! Thanks for your help Hiball. I will keep you all posted.

I'm really enjoying this learning experience because I never really understood how jacks worked. Even though this AC Delco jack is disposable, it's really fun getting a mental grasp on what is going on. That mental process is what helps you diagnose problems. Understanding it is 9/10ths of the repair.

NQ

Its Possible if someone else has messed with the Jack, that the Overload isn't set properly. If its too light it will allow you to push the Ram back in and not lift a load.

You can get a general idea of what your dealing with by removing the safety cap #33 and using a screwdriver turn the 34 completely clockwise (while counting the turns) and see how many complete revolutions you have till it bottoms out. It should be roughly 1 1/2-2 turns out and requires a test station to set properly but you can get it close. If that doesn't fix your problem, remove #34 and check to see if all the components are there, maybe the PO lost some parts?

After re-reading your Post, if you have a Flap when looking down into the cylinder, It should be held on with a Phillips screw and under that flap there is a seat and should be a ball. The flap needs to be positioned to prevent the ball from exiting the Seat, but let hydraulic oil in. The purpose of this ball/Seat is to maintain pressure inside the cylinder till its called upon to exit via the release vein.
 
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EDGAR

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About #38, the ball, it should be there as there is a washer type cover under the cylinder that keeps the ball captive. If the problem is not the overload bypass, as Hiball mentions, it could be precisely that ball #38 that is leaking. I have seem some of the small jacks do the same as you stated and the problem was the ball. Sometimes it can be something is stuck to the seat but other times is the ball itself. If you remove the cylinder, look at the ball with a magnifying glass looking for any nicks, dents or rust. The ball is chromed, so it should look bright and it should have a smooth looking surface and should be perfectly round; anything less and it could leak. If it looks dull grayish, change it. Just know that a new ball should be tapped a couple of times so it seats correctly in its seat. This should be done preferably with a brass punch or anything softer than the ball.

That ball #38 is the one way valve for the ram. When you pump the handle, the ball allows the oil to into the cylinder behind the ram but as soon as you stop pumping, that ball closes against its seat. This ball is holding the weight you are lifting, so it has to seal perfectly, otherwise the arm will come down.

As for the ball under the pump piston, that is the only part there; only the ball. In your jack, the ball is held captive by the copper washer that seals the pump cylinder. In other jacks, the ball is loose and can come out if the jack is turned over. This ball is also a one way valve and it allows the oil to come from the oil tank into the pump cylinder when you lift the handle (by suction) but as soon as you push the handle, the ball seats and the oil inside the pump cylinder is redirected towards the ram. This ball does not has to seal perfectly, but if it leaks a little, you will be pumping less oil behind the ram, taking longer to lift a load.

IMPORTANT: make a mark in the cylinder before you remove it. When reinstalling it, take that mark back to at least where it was before, that way you are close to the torque value for the cylinder when installed at the factory. If you are able, try to go past that mark position just a little bit just to compensate for the already used sealing washer. If it were a new sealing washer, you might get away with less torque, but since you don't know if the old washer is going to end up in the same position in relation to the cylinder as when it was installed, you may need more torque so the cylinder seats correctly over the washer. If the cylinder leaks, because it was not tightened correctly, it is going to be most difficult to diagnose, as everything else, like the seals and the balls, is blamed for the leak before anyone thinks about the cylinder leaking.

All about valve seats: check second page for info about tapping the balls.

http://www.ohiohydraulic.com/enerpac/VALVE SEAT CHART INFORMATION.pdf
 
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noquarter

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Many thanks to the both of you (Hiball and Edgar.) Keep in mind that I have already disassembled and cleaned this jack out previously and as Edgar and the diagram verified, there is nothing more than a washer and ball (28 and 29) under the piston (24). I indeed monkeyed with the overload. It was 7 half-turns from bottoming out when I first took it apart. I even tightened it all the way down (not forcefully - just with the same firmness you bottom out adjusting screws with on carburetors) and the reaction is still the same where something is allowing what I just pumped, to be fed back into the piston. If I had the handle connected (I'm just pumping up and down with a vise-grip currently) it would be the same effect as shoving the handle back up right after I pushed down. That to me points to a failure of 38 so I will drain the oil and take everything from 52 on down off. I will also make a light score mark so that I know where 46 was torque-wise. I had applied quite a bit of force with a pipe wrench and it left a pretty good score mark in 46 - not that it's crucial to the operation of the jack but I could very well end up destroying it if I'm not careful. If something is jammed around 38, I'd like to think I could blow it out with the airgun, however if the problem is corrosion, then it really does need to have an eyeball inspection to verify what is going on. As far as I'm concerned, that HAS to be where the problem lies. Fluid is going right back out past this seal. If it wasn't, the jack would stay pumped up.

Back to the drawing board and I will keep you all updated. Thanks for the lessons!

NQ
 

crackedback

Member
Joined
Oct 9, 2012
Messages
5
Got the old sears jack rebuilt. It now goes up and will at least hold 200#. Haven't had a chance to use it on a car. It hasn't dropped any fluid.

Used a HF impact driver and 2lb hammer to get the peened cover off.

Going to use it tomorrow rebuilding the front end on my Aspen R/T.

Used a HF impact driver and 2lb hammer to get the peened cover off.

Hiball, thanks again for the parts and guidance. :beer:
 

noquarter

Member
Joined
Jun 9, 2012
Messages
10
Good for you crackedback! It's amazing how this little tutorial spawned a plethora of guys who can now rebuild their jacks or at least attempt the rebuild. Anything that gets you out of the "system" of disposal and giving up more of your hard-earned bucks is worth its weight in gold.

UPDATE: The AC Delco 3 ton jack is now fixed...or at least fixed good enough. Before work this morning I disassembled the jack and popped the fill plug so it would have all day to drain. I pulled out all the pieces and parts and immediately noticed that it looked like I didn't get everything lined up quite right down the overload hole (and dang it I tried so hard too!) Anyway, I kept on keeping on and with a 5 foot cheater managed to unscrew the cylinder from the base. All that lay in the bottom though was a plate that didn't seem to have a way to remove it. I figured at the very least I'd just blow out all the passages and when I did the plate flew out. I immediately stopped, listening for the #38 ball bearing to bounce around. Imagine my surprise when it stayed in the hole! Lucky break #1.

I once again blew out all the passages and had a good look at everything and I just wasn't satisfied with the dull colour of the ball seats. I was trying to figure out how I would shine then up when an old tip from my Grandpa came to mind. We used to use drill bits spun between our finger and thumb to clean up seats in old carburetors. Spinning a nice sharp still bit back and forth with your finger and thumb is *very* effective if you have patience. I cleaned up the overload seat and the somewhat questionable seat on #38. Reassembly was a snap until I dropped the tiniest ball for the overload! I froze and listened and heard it ding on a piece of metal on my shop seat. I got down and scavenged all around and nothing - man I was pissed! I tipped the seat on it's side a dustball with a ball bearing in the middle of it fell out of the base somewhere - whew! - lucky break #2. I used a dab of grease to hold the ball in place and using the magnet reinstalled the the overload assembly.

I filled up the jack with fresh hydraulic oil, reassembled the cylinder to the frame and wheels, I pumped the piston with my vice-grips and it worked! Not bad for a FREE dumpster find 3 ton AC Delco jack. I'm stoked and many thanks to Hiball and Edgar here.

Of course the true test will be jacking up a load. At least this time the pressure from the cylinder wasn't going back and forcing my jack handle to shoot up after every stroke.

The only thing I really need to figure out is how to replace the missing #23 which is the clip that interfaces the pumping piston to the handle sleeve #20.

This thread is epic. Thanks for allowing me to share my story with you all here.

NQ
 
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Hiball

Well-known member
Joined
Apr 30, 2009
Messages
14,026
Location
Missery
The only thing I really need to figure out is how to replace the missing #23 which is the clip that interfaces the pumping piston to the handle sleeve #20.

This thread is epic. Thanks for allowing me to share my story with you all here.

NQ

I might have a replacement clip if you can give me some measurements.
 

noquarter

Member
Joined
Jun 9, 2012
Messages
10
Sounds like a plan Hiball. It's going to be somewhat vague as I can't really get a tape measure in there and I really don't know what the original part looks like. I can however get the measurements such as the I.D. of #20, the diameter of the pin #22, and the groove thickness and diameter on #24. Would all of those help? Thanks again Hiball!

NQ
 

noquarter

Member
Joined
Jun 9, 2012
Messages
10
Hey Hiball - I went out to the shop tonight and started taking measurements on the jack. Then I started thinking about making my own clip and after about an hour of monkeying around with a scrap piece of steel using a vise-grip, hammer, bench vise, and a couple of files, I was able to make the missing piece. I need to make a jack handle next, but the jack now holds my weight and it functions very well. Thanks for your offer to sell me the clip and for your previous posts which led me to this point.
 

PA1018

New member
Joined
Dec 15, 2013
Messages
4
Location
Bucks County, PA
Hi, great discussion. First time poster from beautiful Trenton NJ. My old import jack would only go up slightly and then drop. Forget about putting any load on it. Took it all apart, seals looked fine, then I found this on the base of the ram. Busted U cup. Measures 11.5 Tall, 22 i.d., 39.5 o.d. (all mm).

Hiball, is this something I can order from you? Please PM or whatever is easiest. Thanks for all the info!



 
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Hiball

Well-known member
Joined
Apr 30, 2009
Messages
14,026
Location
Missery
Hi, great discussion. First time poster from beautiful Trenton NJ. My old import jack would only go up slightly and then drop. Forget about putting any load on it. Took it all apart, seals looked fine, then I found this on the base of the ram. Busted U cup. Measures 11.5 Tall, 22 i.d., 39.5 o.d. (all mm).

Hiball, is this something I can order from you? Please PM or whatever is easiest. Thanks for all the info!

Pm sent..
 

noquarter

Member
Joined
Jun 9, 2012
Messages
10
Crackedback - lovin' the picture of the Aspen up in the air. Congrats!

As a follow-up letting all of you know my jack is completed. I used an 18" piece of 1/2" gas line (like the non-galvanized version of water pipe) and drilled 2 holes to add 2 5/32" roll pins. One forms the pressure release valve tool and the other pin is used to locate the handle in the jack.

The old AC Delco jack was lifting a 1932 International 1 1/2 ton truck over the weekend.

Thanks again for the help.

NQ
 

30dodgeboy

New member
Joined
Feb 5, 2007
Messages
3
I am pretty much in the same boat as what PA1018 posted above...

A friend gave me an older Sears 2 ton floor jack, its a little bigger and much better made than the 1999 Craftsman 3 ton that I have been using. This jack had a broken gear on the lowering valve (just how does someone do that?!?) so I welded a couple new teeth on and tried it out, Seemed to go up well, but slowly crept down without any load on it. With my 200# on it, it crept more slowly. With about 2000# on it it creept way too fast, like about an inch and a half per second. Handle stayed put and additional tightening of the handle (lowering valve) did not affect the creeping so I had an idea of where to look specifically and tore into it. Aside from a layer of sludge in the bottom of the reservoir and other low places, it looked pretty good. Pretty well made. I like the spring-loaded ball valve to prevent over-extension, and the two screen filters to keep the trash out of critical areas. Its construction looks very similar to what PA1018 posted above. Anyways, I washed all of the parts and after inspection, I see a small 1/8" long crack in the "lip" of the piston's U-cup. The U-cup is a harder whitish plastic and measures 0.863 ID by 1.577OD and has number N80X X molded in it. Any chance you can point me where to get one of these?
Thanks, Art
 
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Hiball

Well-known member
Joined
Apr 30, 2009
Messages
14,026
Location
Missery
I am pretty much in the same boat as what PA1018 posted above...

A friend gave me an older Sears 2 ton floor jack, its a little bigger and much better made than the 1999 Craftsman 3 ton that I have been using. This jack had a broken gear on the lowering valve (just how does someone do that?!?) so I welded a couple new teeth on and tried it out, Seemed to go up well, but slowly crept down without any load on it. With my 200# on it, it crept more slowly. With about 2000# on it it creept way too fast, like about an inch and a half per second. Handle stayed put and additional tightening of the handle (lowering valve) did not affect the creeping so I had an idea of where to look specifically and tore into it. Aside from a layer of sludge in the bottom of the reservoir and other low places, it looked pretty good. Pretty well made. I like the spring-loaded ball valve to prevent over-extension, and the two screen filters to keep the trash out of critical areas. Its construction looks very similar to what PA1018 posted above. Anyways, I washed all of the parts and after inspection, I see a small 1/8" long crack in the "lip" of the piston's U-cup. The U-cup is a harder whitish plastic and measures 0.863 ID by 1.577OD and has number N80X X molded in it. Any chance you can point me where to get one of these?
Thanks, Art

PM Replied to.
 

G20-Budo

Well-known member
Joined
May 31, 2013
Messages
987
Location
Chandler, AZ
HiBall, I just wanted to not only thank you for creating this jack thread, but also for being so helpful to us GJ members with all of your information and replies! I'm considering rebuilding one of my old floor jacks now. :)
 
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