MaxJax Flow Divider

[spazegun2213]

Alright folks, I come seeking hydraulic knowledge. I bought a used MaxJax (because I already had the mounting/bases for the old one) cleaned it up added new quick disconnect fittings, bled the thing and it lifts uneven... like they all do.

I had this problem with my last one and would lift to the first hole, lower, and left again for a full height lift. Same on the way down since it never worked right... but it was in spec, lol.

This one is just out of spec and the higher ram is ~1.75" above the other at the first hole (~1.5" is spec... so not bad). The problem follows the hose, which means its probably the flow divider / combiner.

I've read people trying this control valve and also just replacing the flow divider with something like this but I've never heard if it fixes the problem or will cause more problems with other parts.

I realize I can buy one from Maxjax, but at $300 (cost+tax+shipping) its more expensive than just about anything else out there (given the specs listed on the maxjax site). This is surely the easy button, but given I've had problems with 2 lifts now I wouldn't be shocked if this part makes the problem better, but doesn't fix it.

So I'd love to hear from anyone that has replaced parts on their maxjax with aftermarket, or anyone that knows about hydraulics...

Thanks guys!

 

[petee_c]

My maxjax used to lift level. I installed it myself back in 2011...

I've been using it lately, and even lifting light vehicles like my NB miata, it's going more and more uneven... It's close over 4" out of level by the 1st stop, I lower the car down to the 1st stop to get it level, and then continue on to the final height....

Did you ever resolve this? A new flow divider is $275USD, with shipping and duties, it'll be pretty expensive getting one sent up to Canada...

I wonder if the flow divider is something that can be rebuilt... I've got to think a seal is gone in there somewhere letting fluid travel more on one side, but I haven't tried taking it apart....

 

[Denwood]

I replaced one flow divider and it still lifts about an inch slower on the far side from the pump (I've extended that line about 10 ft). Better bet is the control.

 

[firebirdparts]

I guess you understand how it works, right? You want synchronization by volume, and so the way to get that is a little gear pump that has two outlets. There maybe some fluidic ways to do it, but the little divider from Summit should work in principle.

If there's air in there, then it'll squish and that is going to throw you off in an otherwise perfect system. Which means, oddly enough, you could calibrate it by having the same amount of air in both sides. I don't recommend that. It should bleed without all that much confusion. You can bleed in both directions, if you want to, and need to bleed uphill. I know everybody who owns these things gets good at that.

You could consider adding some features to the controls to allow you to level it manually. That would require you to not screw it up, of course. The jack doesn't know you exist, so

 

[lolaetype]

I assume you've bled the system and have no fluid leaks Do you have a place in your area that rebuilds hydraulic equipment? If so you might take the flow divider to them and explain the problem. See if they have a solution.

I've only had my Maxjax for two years and it lifts evenly. And the way I have mine set up I have 35 feet of hydraulic hose feeding one side and 3 feet feeding the other.

 

[petee_c]

Yeah, i bled the system a few times... it helped a bit. I have not bled it recently, but will try it again when i get home.

I've had it installed for just over 10 yrs. I have extra hose on both sides, running up to the rafters and down to the pump.

Now, the one post always seems to lag the other by a couple seconds when I first start the lift.

Coming down, it's fairly even... Tires will touch down maybe 1 second sooner on the one side then then the other.

 

[petee_c]

I replaced one flow divider and it still lifts about an inch slower on the far side from the pump (I've extended that line about 10 ft). Better bet is the control.

Denwood,

did you get the maxjax flow divider or source something else locally?

 

[Denwood]

MaxJ, sent me a replacement. It pretty much did exactly what the first one did..lifts the far post about an inch slower. My shop is also sloped one inch to the side though, so it's a non issue. The car is actually lifting "level", however I have to run the pump a bit longer to top out the offending post.

I have my posts set up so the pads are level, meaning the posts are not quite plumb.

 

[petee_c]

the flow divider linked in the OP says min inlet flow 8gpm; max inlet flow 16gpm....

the maxjax one says max inlet 3.5gpm

the 110v pump on the maxjax must be slower than most pumps?

Flow Divider

The MaxJax® cast-iron geared flow divider provides precise, equalized lifting by taking a single input flow and dividing it into two separate fluid circuits. The specially designed flow divider is a positive-displacement fluid control device with precise flow division of hydraulic power from one...

www.maxjax.com

 

[petee_c]

the flow divider linked in the OP says min inlet flow 8gpm; max inlet flow 16gpm....

the maxjax one says max inlet 3.5gpm

the 110v pump on the maxjax must be slower than most pumps?

Flow Divider

The MaxJax® cast-iron geared flow divider provides precise, equalized lifting by taking a single input flow and dividing it into two separate fluid circuits. The specially designed flow divider is a positive-displacement fluid control device with precise flow division of hydraulic power from one...

www.maxjax.com

i'm thinking about putting https://www.amazon.ca/dp/B0000AX3M1/?tag=atomicindus04-20 on the faster side....

 

[Denwood]

That should work, and in my opinion is the better solution vs another flow divider.

Here is one of the models linked from an older thread on this issue:

Dynamic JP-FC Micrometer Adjustment Knob 3/8-NPT

Dynamic JP-FC Micrometer Adjustment Knob 3/8-NPT. Usually ships in4 days. Buy it and Save at GlobalIndustrial.ca

www.globalindustrial.ca

 

[petee_c]

i'm thinking about putting https://www.amazon.ca/dp/B0000AX3M1/?tag=atomicindus04-20 on the faster side....

well that item fixed it. I also needed a 3/8NPT male/male adapter, and a union of sorts if your fast side is on the same side as the input to the flow divider. It took a couple of short lifts with the arms unloaded to get the arms to be close to each other , and then I put the miata up on it. I got the arms to be within an inch of each other at the top with a couple minor adjustments.

I need to the put Golf up on it next to do the oil change... Don't know if i will need to adjust it further for different weights of vehicles.

 

[petee_c]

lifted the 2015 Golf TDI - curb weight ~ 3100lbs. Reached the top rung within 0.5" of each other without needing to adjust the valve further.

The Miata probably weighs about 2300 lbs.

Will be interested to see how the lift does in terms of evenness when the q7 goes up (over 5000lbs), or the riding mower 600lbs for changing the blades.

 

[NewShockerGuy]

Older thread but wanted to check in to see if you have to keep adjusting the valve based on what you are lifting?

IE: When you lift something that is 5000lbs did you adjust it more only to find out that the side with the valve on it then lifts even slower if there is something lighter than the 5000lbs?

Thanks,
-Nigel

 

[petee_c]

Coming back here, because it seems like I have to adjust the valve occassionally to even out the the lift arms.

We've added 2 EV's (~5000 lbs) to the stable, and it does seem to make a difference between lifting them vs the VW Golf or NB Miata. I may look at an aftermarket flow divider with a lower flow rating to solve the uneven issue.

My latest research seems to be pointing to the fact that the maxjax flow valve is rated for a lot higher flow than what is needed, and the 'flow-by' (like blow-by for oil consumption) in the valve is too much for the volume that is actually moving in the system....

According to the interwebs, the maxjax requires 7 quarts of Fluid, and takes about 50-60 seconds to go from the floor to max height, so that's right around 2GPM flow. The maxjax replacement flow valves are 3.5GPM

 

[Bill-banger]

Old thread, just revived, so I want to chime in. My MaxJax is about 15 years old now, ive added extension hoses and better quality dry couplers, both cylinders were replaced under warranty, and I replaced the ATF with hydraulic fluid, ISO 32 several years ago.
My lift has always raised unevenly, and gotten worse over the years. I hesitate to buy a new divider valve(now $424), but I did buy an aluminum one from a hydraulic supply firm awhile back but have yet to install it. I've bled relentlessly, no help.

So I've lived with this problem all this time and really would like to solve it, most discussions are years old as is this one. It seems BendPak fixed most issues that Dannmar had but they won't help with our original units, can't say I blame them. Any suggestions are welcomed.