Hydraulic reservoir seal? Missing?
 

My '94 Funlite seems to "purge" itself of some valuable (and messy!) ATF fluid if I don't let it down in short, well-paused bursts. It appears to be leaking from the top of the hydraulic pump itself, almost as if my fluid reservoir cap is missing a small o-ring of some type.

Anyone know anything about this?

According to the PO, he had noticed the same thing. Seems unusual to me. Other Hi Lo models we looked at (some much older than this one) raised and lowered with ease - without the big fluid mess in the driveway.

Anyone know anything? Am I missing a small seal of some kind?

And one more thing, while I'm asking -

The PO said he preferred to NOT lower the top all the way down. Ever. He got it close, then called it good.

Does this seem unusual to anyone? I don't understand why he would do that? Is it related to the hydraulic pump? I have been lowering it all the way down - with no problems. What's the protocol here?

Put it all the way down, or the weight of the top is resting on the cables, won't hurt the cables as much as the stress on the cable anchor points on the top half and the pulleys.

Agreed! The top needs to be resting on the supports at the base - all weight off the cables.

- Jack

I would just call J&R, there must be something, either an adjustment to slow it down when going down or like you said a missing something, but the tank does have to breath...

it sounds like the vent is acting up,or is over filled.

I'll get out my manual and see what I can find as far as vents; I'm assuming they just allow air to be purged from the lines/system - is that right?

I can also slow down the descent speed - but according to my manual, this shouldn't need to be done very often, or at all. Manual calls for about 12 seconds for the lowering of the top, and that's roughly where I'm at.

Where should I look for vents? On the pump itself? It looks the reservoir cap should be an air-tight seal - but the ATF still comes running over, fwiw.

i just looked at parts sheet that came with my 1999 the fill plug is also the vent part number 03866

here is a copy of the pump with parts number.

There is an adjustment on how fast it comes down, think it is in the manual, will have to check.
Yes the down valve can be adjusted and it is in the manual, how to adjust.

I wonder if this cap/vent can be cleaned. Anyone ever found a plugged vent hole in their cap?

I did read in the manual that the descent speed can be increased/decreased...but I'm more concerned about why the fluid is pushing out. I think the rate of descent is ok for now. I THINK. Haha!

the VENT/cap lets air in while oil is sucked from resivior to fill the cylinder, and when cylinder is going down, oil rushes back into resivior. if it was no vent the resivior would have to crush like a can when up, and expand like a baloon when down.

My guess, and it was only a guess, that possibly fluid dumps into top of resivior, and if flowing too fast (described by you, that if you stop a few times it doesnt leak?) my idea was maybe it is being forced by air rushing out the cap/vent? Makes sense if slowing the top lowering process is a fix to a symtom but not the touching the real problem?

More likely, there is a the real possibility, due to how hard it can be to check level, & that it is too high? you have to have it all the way down, to check oil, and from POSTERS on here, then you cant see in easy to check. My 5th wheel has an access door that is always accessable so it is easier to check when down.

So, does it gush out only at the last bit of lowering, when you dont do your 3 time pause while lowering? or does is gush out the whole time if you dont pause? that would help the diagnosis, if it would leak if you dont stop but leaks all the way down, maybe slowing it will stop it from being blowing out? if it only leaks a bunch at last bit, it could be too full?

I am just guessing withwout being there, and I am not some expert, but I deal with hydraulics on other things from time to time on the farm.

All good points/questions, Sting32 -

Do you think the fluid level might be too high? I'll have to check this eve after I round up some alternate ways to check the fluid levels.

After I adjusted the cables last night (so that the top would raise evenly), I noticed that it took longer than normal to "lock" the safety bar in place. I had assumed (after seeing the fluid run all over the pump) that it was in fact LOW on fluid - but perhaps it has too much!

My top still needs to come up about 1/4" or so - maybe 1/2" (I'm anal like that) - but I'm wondering if I've maxed out my hydraulic system. That is, I'm over-filled on fluid but still not able to raise it enough to latch the safety catch.

My gut instinct says that I'm low on fluid, as it's pushing it out the pump upon lowering the top, and that's also the reason why it's taking longer to latch the safety. I'll try and fill the reservoir again this evening, and at the same time slow down the descent speed to see if I can't find a happy medium. Something that raises/locks the safety latch relatively quickly, and something that allows the top to lower without purging fluid all over the place.

Does that make sense? Kind of confusing, I realize...

There is the possibility that some one put the wrong fluid in and it is foaming. This would cause it to blow out the vent. If it was mine I would put the top down suck all the fluid out of the tank and put Dexron in, I would do this a couple times, if this doesn't fix the problem, I would slow it down some, if it fixes the problem, what does a few more seconds mean.

Are you sure the reservoir wasn't overfilled at some point? The level should be about an inch down from the top when the trailer top is in the down position. I know it is hard to check when in the down position but that is when it must be done.

No, I'm not sure. I'm going to check it this evening to see what I find.

I hope it's not going to take a flush/refill - that sounds somewhat cumbersome. But if it's necessary...

The fluid should gush out only one or two times of lowering before all the excess gets forced out. After that there should not be enough left to overflow the reservoir. If it keeps coming out after that there must be other problems.

:mad:

OK - in the past few hours, here's what I've learned:

1) My hydraulic pump is definitely leaking, and it's definitely coming from the filler cap. I lifted it up then used the manual drop to bring her down so I could watch from up front. Sure enough, there came the fluid.

2) I know the fluid level was relatively close, as I'd just refilled and checked it. It measured to within an inch on the top of the hydraulic cylinder after adding ATF.

3) I adjusted the descend speed to what I believe is the absolute LOWEST it will respond to. I know this because I initially went too far, and the solenoid that triggers the lowering valve was not functioning. I backed out the cap screw until it just BARELY made contact - lowered it - and still saw fluid coming out the filler cap/vent cap.

Because it was late (and dark), I didn't refill it and try the lowering procedure in short bursts - but according to the PO, if it's lowered in short 2- or 3-second bursts, the fluid won't come gushing out.

Could there be air in the lines causing all this?

Furthermore, I timed the lift time this evening just to give me a benchmark. 40 seconds with the lower fluid level, 37 seconds once I'd filled the reservoir. Granted, the battery might be less than 100%, but it had been on the charger for about 2 hours at that point. Not sure what state my battery is in, honestly - but it was purchased brand new just last week.

Just as a point of reference, I looked at an '83 Hi Lo, 21' model - and it raised and lowered PERFECTLY - literally the 12-second lift/lower, just as promised in the near 30-yr-old literature. Granted, the owner was very detail oriented, and knew how to care for his stuff, which I'm not sure I can say for the PO of my '94 Funlite.

Here's my concern: if the lifting/lowering takes so much pampering/babying, what's going on? Why is this not working as it should be? Where's the bottleneck in this whole system? I can't find any other ATF leaks anywhere, so I'm rather convinced it's losing all its fluid out the filler cap.

And another detail - the hyd. pump cycles through loud "squealing" sounds as it's raising the upper; it becomes louder, then cycles through it, then maybe 12-15 seconds later, here it comes again. I noticed it maybe 3 or 4 times during the lifting cycle. Any thoughts on this? Is that air in the lines? It sounds as though the hyd. pump is working much harder during these times. It may not be, but it sounds like it is.

Bend lift rod underneath? I haven't noticed it. And wouldn't that make it squeal/howl at roughly the same time in the lift cycle each time? That's not necessarily the case with this thing.

That's a lot to toss out there - but I'd love to know what you think.

Do you keep your fluid level an inch down from the top? My manual reads "within an inch" from the top. I added ATF to within about 1/2" of the top.

Just re-reading and noticed that little detail...

That level is with top down and the pump does not pump while it is going down only in going up. It uses the weight of the top to lower it you are just opening a valve with the switches to let the fluid back into the tank.