Lincoln Jack 93667 C Service Jack Question

[doogdoog]

Aloha,
I bough a 4t Lincoln 93667C service jack used, from a retiring transmission shop owner. It worked when I bought it but I had it in storage for about 20 yrs. I tried to use it but manually operating the handle, the jack only pump up and then stops it hits the load. I tried the air assist and it works fine and lifts the load. I am thinking that when the jack rises without a load that it is the fast lift to get to the load faster. Am I correct? It has two rams, a small one and a larger one so is the smaller one the high pressure lifter one? There are 4 plugs on the ram, 1 small plug and 3 bigger plugs. Is the small plug for the high pressure ram? Any thought on the problem?
Thank you,
doogdoog

 

[doogdoog]

Anyone???

 

[doogdoog]

Anyone??????

 

[doogdoog]

I removed A plug and removed a 5/16" ball and then a 3/4" ball stop plug and a 7/32" ball. Every thing looks good but I cleaned the balls and tapped the ball with a brass rod to make sure that it was seating correctly. I thought that it would cure the problem but it still exists. I am sure that it is drawing oil from the reservoir but I would think that there has to be a very bad leak to not even trying to lift a load. The only thing that I can think of now is the small piston. Any thoughts? I also want to remove the release stem but there is X in the picture preventing this. Do I have to split the jack sides to remove it?

Mahalo,
doogdoog

 

[doogdoog]

I found out that I would have to split the jack to remove the release valve stem and sure is a lot of work for such a simple thing. Any jack people familiar with this type of jack???? Anyone?????

Mahalo,
doogdoog

 

[doogdoog]

Aloha,
Anyone know of a good forum about fixing jacks? I have some questions about my service jack to help fixing it.

Mahalo,
doogdoog

 

[Hiball]

Aloha,
Anyone know of a good forum about fixing jacks? I have some questions about my service jack to help fixing it.

Mahalo,
doogdoog

You would be hard pressed to find a forum with more hydraulic Jack resources than GJ. The info is out there, one must simply put some search time in. In your particular case, you admittedly have a jack that sat for 20 years, there is no magic pill. It could be that the power side Vees are kaput, could be a valve issue on the power side, but my suggestion based off the info given is a complete tear down and inspection. Yes... It's a job to split the frame, Manufactuers like Walker didn't want the average joe working on there stuff.

 

[doogdoog]

Aloha Hiball,
I posted a reply to your post but I guess I didn't post it or somehow it got lost so I am re-posting. Thanks for the reply and sorry about the repeated postings but I was getting worried that no one would reply to it. The air assist side lifts the load and also holds it in position so great for that. I have checked all the balls and seats under the four plugs and the seats and balls are in good condition. The large piston lifts the saddle to the load but the small piston fails to lift the load. Does the safety valve have separate fluid path from the air assist side and the small piston side? Do you think that it could be the safety valve that is the problem? I will check the vee on the small piston but I will have to make a spanner wrench first. The very last resort will be tearing down the jack and that looks like a lot of work. LOL. Thanks again Hiball and hope to hear from you soon.

Mahalo,
doogdoog

 

[Hiball]

Aloha Hiball,
I posted a reply to your post but I guess I didn't post it or somehow it got lost so I am re-posting. Thanks for the reply and sorry about the repeated postings but I was getting worried that no one would reply to it. The air assist side lifts the load and also holds it in position so great for that. I have checked all the balls and seats under the four plugs and the seats and balls are in good condition. The large piston lifts the saddle to the load but the small piston fails to lift the load. Does the safety valve have separate fluid path from the air assist side and the small piston side? Do you think that it could be the safety valve that is the problem? I will check the vee on the small piston but I will have to make a spanner wrench first. The very last resort will be tearing down the jack and that looks like a lot of work. LOL. Thanks again Hiball and hope to hear from you soon.

Mahalo,
doogdoog

The Air assist side doesn't hold the load, the ball/seat has that responsibility. Since the Jack is working on the Air side, that eliminates the Main ram seal (although 20 years in storage gives me the creeps). It's either a missing Component, improper order in the valve for the power side, Kaput Vee's on the power piston. It's physically possible to inspect the power side piston without splitting the frame, it will require unhooking the linkages, reccomend elevating the rear of the Jack, unscrew the gland and pulling "straight out". It will take some manipulation to remove and reinstall the packing using this method, but it can be done.

 

[doogdoog]

Aloha Hiball,
Thanks for the reply and I will try to remove the small piston to check it out as soon as I make the spanner wrench. I could probably use a screw driver or punch but I don't want to hammerjang the gland nut. I checked all 4 the plugs and their contents and it looks like everything is there and in the right order according to the drawings. Do you think that there is a possibility that the overload safety valve is at fault for the high pressure pump side? Just asking because my 1 1/2T lincoln was overloaded and it popped the safety valve. It would not reset by itself so I took it in for repairs but the owner would not tell me what he didbut he did tell me that I owed him $150.00, LOL.

Mahalo,
doogdoog

 

[doogdoog]

Aloha Hiball,
Yes! Ok Hiball, I removed the small piston and pulled out the piston. The end of the piston only had the point where the cup goes and nothing else. I tried to look into the cylinder but could not see any part of the cup or whatever else that was attached to the end of the piston. According to the drawing, there is suppose to be:
1) (232968 back-up washer)
2) (232969 U-cup)
3) (204301 washer)
4) (2 213152 packing ring)

Is this correct? How big is the back-up washer? I didn't see it in the cylinder or maybe it is stuck at the end of the cylinder? Would you know if the piston had a leather cup or some synthetic type of cup? Looks like the problem may be solved but now to locate the parts. Any good parts place to look at? I hope I don't have to purchase the whole rebuild kit for these few items.

Mahalo,
doogdoog

 

[Hiball]

Aloha Hiball,
Yes! Ok Hiball, I removed the small piston and pulled out the piston. The end of the piston only had the point where the cup goes and nothing else. I tried to look into the cylinder but could not see any part of the cup or whatever else that was attached to the end of the piston. According to the drawing, there is suppose to be:
1) (232968 back-up washer)
2) (232969 U-cup)
3) (204301 washer)
4) (2 213152 packing ring)

Is this correct? How big is the back-up washer? I didn't see it in the cylinder or maybe it is stuck at the end of the cylinder? Would you know if the piston had a leather cup or some synthetic type of cup? Looks like the problem may be solved but now to locate the parts. Any good parts place to look at? I hope I don't have to purchase the whole rebuild kit for these few items.

Mahalo,
doogdoog

My guess is that it along with Ucup is still in the bore, the Ucup is probably in pieces. The back up washer is probably about the thickness of a nickel. Obviously it's your Jack, but at this point and knowing the history of sitting in storage for 20 years. I can promise you the main ram Ucup isn't far behind from disintegrating, when jacks sit and don't get used, that's extremely hard on them, the seals lose the elastomers that keep them pliable and they fall to pieces. The next thing to worry about is that more than likely parts of that pump piston Ucup has likely made its way into the valve system, regardless you will have a devil of a time getting the bore cleaned without the luxury of having the valve clear so you can back flush the system.

 

[doogdoog]

Aloha Hiball,
Thanks for the reply and I was wondering if that washer could be jammed up in the bore so if it is the thickness of a nickel do you know the approx. diameter? I looked into the bore but couldn't see it. Do you know if a rebuilt kit comes with both leather cups and synthetic cups? The reason I am asking is because back in the day, I ordered a repair kit for a bottle jack and they asked me if it was leather or synthetic. I pulled out the ram and it was leather so they sent me a leather cup. Are they interchangeable?

Mahalo,
doogdoog

 

[American Locomotive]

The small ram piston is the one that lifts it quickly, and the large piston will be the one that handles the load.

 

[doogdoog]

Now this is very confusing because the jack lifts until it reaches the load and then stops. The small piston didn't have any cup on it so I don't think that it could lift the saddle to the load. I could be wrong but I am thinking like how a 2 stage air compressor works for ex. the large piston loads the small cylinder and then the small cylinders piston compresses further to a higher pressure to ease the load. Now you got me thinking but I still think the small piston is the high pressure side because of the copper gasket that it uses.

Mahalo,
doogdoog

 

[Hiball]

The small ram piston is the one that lifts it quickly, and the large piston will be the one that handles the load.

With all due respect, that is not correct.

 

[Hiball]

Aloha Hiball,
Thanks for the reply and I was wondering if that washer could be jammed up in the bore so if it is the thickness of a nickel do you know the approx. diameter? I looked into the bore but couldn't see it. Do you know if a rebuilt kit comes with both leather cups and synthetic cups? The reason I am asking is because back in the day, I ordered a repair kit for a bottle jack and they asked me if it was leather or synthetic. I pulled out the ram and it was leather so they sent me a leather cup. Are they interchangeable?

Mahalo,
doogdoog

The diameter will be the same as the pump piston, kits vary from supplier to supplier, so it will be best to ask them personally. The leather Vees and Ucup are not interchangeable, you will need to have the Ucup.

 

[doogdoog]

Aloha Hiball,
What holds the U cup and washer from coming off of the pointy piston part? When I took the piston out, there wasn't anything there so I am not familiar of the setup so would it be U cup, washer? What holds the U cup and washer on the piston? Does the washer come with a rebuild kit and if not, would I be able to buy it separately? I went to the HPS supply site but it says that their store is closed so do they have another site?

Mahalo,
doogdoog

 

[Hiball]

Aloha Hiball,
What holds the U cup and washer from coming off of the pointy piston part? When I took the piston out, there wasn't anything there so I am not familiar of the setup so would it be U cup, washer? What holds the U cup and washer on the piston? Does the washer come with a rebuild kit and if not, would I be able to buy it separately? I went to the HPS supply site but it says that their store is closed so do they have another site?

Mahalo,
doogdoog

The fat side of the point holds the Ucup on, in turn the Ucup holds the backup washer on behind it. HPS doesn't or didn't have a online site, it will require a phone call be made. In regards to what is included in the kits, again it will vary from supplier to supplier, its best to Ask to make sure there isnt any surprises.

 

[doogdoog]

Aloha Hiball,
Thanks for the information but let me get this straight, "The fat side of the point holds the Ucup on, in turn the Ucup holds the backup washer on behind it. ". The washer goes on the pointy side first and then the U cup?

Mahalo,
doogdoog

 

[American Locomotive]

With all due respect, that is not correct.

Are we talking about the pump, or the lifting ram? because it doesn't make sense for a small ram to do the heavy lifting, but it does make sense for the small piston pump.

 

[doogdoog]

I made this simple spanner to remove the gland nut and also this little funnel. Yes, I know you could use a punch, brass punch, screwdriver etc but I like making tools. The diam. of the wire is about approx. 7/32" and it is piano wire (hard stuff).
Mahalo,
doogdoog

 

[Hiball]

Are we talking about the pump, or the lifting ram? because it doesn't make sense for a small ram to do the heavy lifting, but it does make sense for the small piston pump.

We've been talking about the pump Pistons, in this particular Jack it has "2", one is the power side (small one) and the other one is the speed side (bigger one).

 

[doogdoog]

Aloha Hiball,
I have a stupid question to ask about the small piston U-Cup and washer. I received a repair kit today but there seems to be a lot of parts and I would assume some would be for other similar jacks. Since I didn't have any U-cup or washer when I removed the piston, I don't know what to replace it with in the kit. I will send a picture of the kit that I alphabetized and was wondering if you could point out the ones to use. There are several nylon washers, 3 hard leather cups? not too sure, and some other parts. Can you describe the parts needed for the piston or point it out on the picture?

Mahalo,
doogdoog

 

[mikegt4]

I just completed a rebuild of a Lincoln 12T bottle jack. My rebuild kit covered several related models and running changes. It makes sense to package parts for different versions together instead of a kit for each iteration of a design. It can allow you to take advantage of running improvements.

When I disassembled my jack I matched each part with a new one that was an exact match then figured out which new part replaced an unmatched old part, some where completely different but worked well. Size usually is a good indicator of where the part is intended to go.

 

[doogdoog]

Aloha mikegt4,
That's what I did long ago, matching part for part on earlier rebuilds but when I pulled the piston, there wasn't any U-cup or washer to follow. I can guess on which U-cup but I was thinking that the backup washer was steel and the kit only has nylon and some black rubber looking rings. There's a white nylon washer approx. 5/8" in diam. and about 1/16" thick but it looks too thin to backup the cup. Well thanks anyway andhappy days with your jack.

Mahalo,
doogdoog

 

[doogdoog]

Aloha Hiball,
I ordered a rebuild kit and the U-cup looks ok but the backup washer doesn't. I slipped the backup washer over the pointed end of the small piston but it would not go over the last land because the ID is a little small. The washer measures 1/16" in thickness and I think should be 1/16" thicker to make it 1/8". I looked at the website where I bought it from and it shows a picture of a small piston with the backup washer and U-cup installed and the washer looks like 1/8" thick. What do you think?

Mahalo,
doogdoog