Need help! Maxjax Pump Replacement or Fix.

[deee46]

Hello guys, 5 year old maxjax pump finally bit the dust and i need help in a replacement or fix if any, issue is its not pumping fluids enough to lift anything, if i disconnect the quick disconnect and start the pump, fluid comes out but not powerful enough.

a coworker has a working maxjax power unit so we tested it on his cart and all is well, i even tried to swap the flow divider and its not the issue as mine works and vice versa so 500% its the pump.. also tested just 1 post with the same result only goes up 5 inches max ..

anyways a fix perhaps? but most probably a replacement.

1: can i replace just the pump? there are no marking on my pump so i cant google what i need to buy? tried calling benpak but i just put on hold for about 45min and i just hang up.


2: or can i replace it with a different pump say the one from ebay or amazon? 220v and higher capacity? i wont be using the cart anyways and will be mounting the pump in the wall? will it work?

eg :"Happybuy Hydraulic Pump 220V Hydraulic Car Lift 2.2KW with 10L Steel Oil Reservoir Tank Hydraulic Power Unit for Auto Repair 2950PSI"

Thanks all in advance.

 

[finn]

The pump and motor are typically proprietary designs On these things and it usually isn’t cost effective to replace individual components, if they are even available, with the possible exception of a high price commercial lift like a Mohawk.

The good news is that the pump-motor power packs seem to be universal and readily available. There are numerous Chinese knock offs which may or may not be the same unit with different labels.

I paid a little more and got an SPX Stone online to replace the pen Chinese power unit on my Bendpak which had a shorted motor field winding.

Prices and shipping charges were all over the map.

 

[Christos]

Resurrecting an old thread, but I have the same question. I bought an older MaxJax new, installed it, and it is not able to lift cars. It lifted my old VW Jetta, which weighs very little, but anything heavier would not lift. I suspect a problem with the pump. I did bleed the cylinders many, many times, no luck. Any other suggestions?

My next plan is to disassemble and clean the pump, but just in case, can I use a replacement such as the cheaper units from Amazon? They seem to run at a higher pressure (2950 psi) than the MaxJax original, would that be a problem?

Here is one, for example: https://www.amazon.com/dp/B074XL4S5Z/?tag=atomicindus08-20

 

[AC-WC]

As frustrating as it is I would either get back on the phone with Bendpak OR send them an email. They have the parts and knowledge and should be pretty good to work with once you get them to respond.

 

[Christos]

Perhaps you are right. I tried talking to them three years ago when I first installed the lift (long story, different house and a move during COVID), but all they would say was that I was not the original owner and warranty does not apply and wanted to sell me a new motor/pump assembly for $500. I was so frustrated I decided there was no point talking to them anymore.

I need to take the pump apart. It could be something very simple, such as dirt caught in the check or relief valve.

But the general question remains. Are we able to use a different motor/pump assembly with the MaxJax?

 

[jonesg]

But the general question remains. Are we able to use a different motor/pump assembly with the MaxJax?

why not, I wouldn't choose the cheapest one, in fact I'd pay the extra $50 and buy the one from bendpak.

 

[Christos]

Which one? Some Chinese power units are under $200, Bendpak seem to be over $600.

 

[finn]

As frustrating as it is I would either get back on the phone with Bendpak OR send them an email. They have the parts and knowledge and should be pretty good to work with once you get them to respond.

When my motor failed, BendPac answered my email within a day. Unfortunately, the pump was available only as a pump and motor assembly. No individual parts.

 

[finn]

Perhaps you are right. I tried talking to them three years ago when I first installed the lift (long story, different house and a move during COVID), but all they would say was that I was not the original owner and warranty does not apply and wanted to sell me a new motor/pump assembly for $500. I was so frustrated I decided there was no point talking to them anymore.

I need to take the pump apart. It could be something very simple, such as dirt caught in the check or relief valve.

But the general question remains. Are we able to use a different motor/pump assembly with the MaxJax?

Yes. I chose an SPX Stone. It was cheapest through Best Buy Automotive, and was a direct fit for the BP Chinese original. All ports and mounting holes lined up.

SPX Stone is a name brand, Mexican Sourced, and not the cheapest.

 

[mike93lx]

Which one? Some Chinese power units are under $200, Bendpak seem to be over $600.

The one that matched on flow and pressure. If you don't have specs for those, you have to guess

 

[Christos]

You are assuming that finding the specs to compare is easy. I wish.

Let me contribute some material. The first is a picture of the label on my power unit. Important numbers:
Wuxi Deli Hydraulics Co.
www.wx-dl.com
P/N: YBZ5-E0.8B 8F 1/AMQOT4
Pressure: 1920 psi
Tank: 1.56 GAL
RPM: 3450

The second document is a catalog of power units from the same company (Deli). The one that seems to match more closely to mine is on the second page, fourth from the bottom (it has an F0 instead of an E0 in the part number).

Visually, my power unit looks identical to this one: https://www.bendpak.com/car-lifts/hydraulic-power-units/e12b3f1/ but the specs are different (this is apparently a 220V, lower RPM unit). Also, this Bendpak unit is over $700.

Or I can buy this one, for $180.99: https://www.vevor.com/hydraulic-pow...ack-220v-3hp-s3-auto-universal-p_010853977791 This has a more powerful motor and lower motor speed.

I hope you can see my confusion and why I am asking for alternatives. How important is it to match the specs exactly? Will I blow my cylinders/hoses if I use a different unit?

 

[finn]

After looking at how simple these power packs are, I suspect the most important spec for a lift application is the tank size, to match the hydraulic capacity of your cylinders.

They consist of, from memory, an electric motor, coupling to drive the pump, aluminum pump housing, gerotor pump elements, spring loaded check valve (relief valve) , release lever to lower the lift, and a couple of ports in the pump housing for hose connections.

Take yours apart and spend a few minutes figuring out how it works.

The only things that can really go wrong is the motor may burn out, the aluminum housing could score, debris could jam the gerotor elements, or the relief valve could leak because debris got on the seat.

 

[mm08822]

Look at the working pressure ratings on the hoses. Stay way below the burst pressure.

The flow rate can be calculated by estimating how fast the lift raised and calculating 2x the volume of a cylinder.

Knowing the volume of the cylinders and hoses + ~10 - 25% would give you reservior capacity.

If the new pump unit doesnt come with a pressure regulator, you may want to consider adding one if your replacement pump is capable of much higher pressures than the original.

 

[nadogail]

Call your local Hydraulic Repair Shop, they will be able to answer your questions and supply replacement parts.

 

[Christos]

Thanks everyone, great discussion. I will disassemble the unit and see if I can fix it. As finn said, these things are not very complicated. I will report back in a week or two.

FYI, I tried taking it to a tractor repair shop and they adjusted the check valve, charged me $100 and returned it to me pretty much in the same condition. I have to find a better and more honest shop.

 

[mm08822]

Thanks everyone, great discussion. I will disassemble the unit and see if I can fix it. As finn said, these things are not very complicated. I will report back in a week or two.

FYI, I tried taking it to a tractor repair shop and they adjusted the check valve, charged me $100 and returned it to me pretty much in the same condition. I have to find a better and more honest shop.

Search floor jacks, hydraulic jacks in GJ. There are several mentions of hydraulic parts shops selling seals, gaskets. See if one of those places can identify pump, etc. Send pic and detail of the lift it is from.

 

[Christos]

I was finally able to investigate more. I currently suspect the release valve. When the lift is under load, I can hear a periodic "squirt" sound, which I believe is coming from the valve (I used a mechanic's stethoscope). I was able to remove the valve and inspect it (see picture), but could not see anything obviously wrong. I squirted some brake fluid through the holes with the valve both open and closed and reinstalled, but that did not make a significant difference (maybe it got slightly better in the sense that the lift went a bit higher before stalling).

The valve seems to be an M19x1.5 and the overall length is about 62mm. I found several on eBay that seem to match, but they all ship from China (long shipping delay). I ended up ordering one from Amazon that is longer (72mm) but otherwise seems similar. We will see it it matches, and more importantly, if it fixes the problem.

If anyone has any thoughts on other things to try I am all ears.

 

[Christos]

Well, I got my Halloween present!

First, I replaced both the lowering valve and the relief valve with a pair I bought on Amazon. Note that I bought a 72mm lowering valve, but the lift needs a 62mm valve (see picture in my previous post). Nevertheless, the 72mm valve worked, although the lowering handle was sticking out. However, that made very little difference. But then, After opening the oil cap and with the lift running but stalled, I noticed quite a bit of fluid leaking back into the tank from the direction of the adjustable relief valve. Not good.

I first tried to adjust the valve, and found it tight all the way (I assume maximum pressure - not good). So I decided to remove the adjustable relief valve. The first picture shows what I found. Look at the tip, as you can see the o-rings were torn. There was a black and a clear one, and both were damaged (see the second picture). You can also see some metal shavings that came out with the valve, probably from when it was tightened all the way.

Two new green o-rings later (both identical, I did not have a clear one) and the lift is now working! It lifted a small car all the way up with no problem. I backed up the adjustable relief valve a bit but did not adjust it, I need to hook up a pressure gauge for this. It is probably too high. I even put back the original lowering valve.

The tag on the lift says it was made on 09 5, which I assume to mean Sept 2015 (or is it 2005?). I bought it from the original owner in 2018 who never installed it. It did not work then, and I was never able to fix it until today. Life and a move three years ago got in the way, so the lift sat for three years. I finally installed it a few weeks ago at the new house and really got down to investigating the problem. It is such a relief (and frustration) to find that the problem was so simple (I even had the 0-rings) and get it to work for the first time in five years!

 

[AC-WC]

A less than 50 cent cost for materials -that's a win in anybody's book!

 

[The Cobbler]

great story that I can relate to.
life gets in the way of so many things. procrastination adds to the pile in my case.
Just think how proud you are for being able to fix it for a few $$$ vs buying a new pump. that's a total win in my opinion.
I know when I figure something out like that, I am pleased that I know what I know

 

[Mr onetwo]

Well, I got my Halloween present!

First, I replaced both the lowering valve and the relief valve with a pair I bought on Amazon. Note that I bought a 72mm lowering valve, but the lift needs a 62mm valve (see picture in my previous post). Nevertheless, the 72mm valve worked, although the lowering handle was sticking out. However, that made very little difference.

Could you post up the part numbers or links to what you bought on Amazon please?

 

[Christos]

Here is what I ordered on Amazon:

https://www.amazon.com/dp/B0CCLM3CZV/?tag=atomicindus08-20

But that's not what I got. I received a valve that was black and different shape, see picture. It worked, but the handle no longer fit properly on the pump body because of the longer valve. It can, however, thread on and it's reasonably secure.

My investigation revealed that there are two lengths for these valves: 62mm and 72mm. The Maxjax has a 62mm valve. Then, there is the thread diameter and there are also two options: 19mm and 20mm. I ordered the 19mm based on my measurements, and even though it seemed a bit loose, it fit.

There are also handles for each of the lengths. If you search on eBay you will find them, see this for example: https://www.ebay.com/itm/285163860002.

If you don't mind the wait, you can order valves and handles from Allied Express. I ordered the 72mm handle and a 62mm valve from there since it was cheap. I will update this post once I receive them.

Here is the valve: https://www.aliexpress.us/item/3256...st_main.5.54e11802Kx9uMa&gatewayAdapt=glo2usa

and here is the 72mm handle: https://www.aliexpress.us/item/3256...t_main.11.54e11802Kx9uMa&gatewayAdapt=glo2usa

If I can get the 72mm valve and handle to work I think I will go with that, since the original handle seems too close to the pump. We will see.

 

[bb29510]

stone manufacting

 

[murphthelab]

Resurrecting (again) this old thread. Struggling with a sudden power unit failure, original MaxJax. I have the 110v unit, and when power button is activated, it "shudders" and makes a kind of rattling sound. The nearby lights (on same branch circuit) flicker, suggesting the motors influx current is repeating or cycling along with the shudder. No lift at all. No reason to assume and blockage in the flow divider or the lines.

Likely culprit? Motor? Seized pump?

Maxjax power unit replacements are now up to $825!

I would certainly entertain rolling the dice on a ~$200 Vevor type power unit, but no such thing as a bolt-on or even direct replacement seems to exist. Everything other than the Maxjax ($825) unit opens a pandora's box. Metric/SAE fittings mismatch. Potential flow/pressure mismatch. Most units would force me to go to wall-mount, requiring new hose and accessory purchase.

I would go to wall mount, but why can't there be a power unit that matches closely to what Maxjax uses? There are SO MANY units out there. Crazy a match is not easily found.

 

[murphthelab]

A bit more detail. I opened the switch box on the power unit. The button switch connects to a wiring junction device, which looks like a soft-start perhaps? Picture is attached. The shuttering sound I heard was this junction device clicking, as the green part raises up and down rapidly. Like a magnetic engagement that won't stay engaged.

So far unable to locate a replacement product, or a technique for verifying whether this switch-junction device is the problem, or the problem is behind it in the motor.

Thanks for any ideas or suggestions.

 

[Snip's]

Quick Google search found this...

Can't tell if yours is NC or NO


https://www.finglai.com/products/contactors/contactors/CJX2/CJX2-1801-220V.html

 

[murphthelab]

Thanks for that. Just before seeing your response, I tried manually pushing down the plastic contactor piece, and the pump and lift started working. So good news there. My power unit is 110v, and after a bit of hunting, I found and purchased the item in the attached from Amazon. Be here tomorrow. And yes, my switch is normally open, so confident this is NO.

Will report back whether this fixes it. I guess theoretically it could still be a low voltage condition on the branch circuit causing this shutter.