# Engine hoist problems



## Caps18 (Jun 8, 2008)

I am borrowing an engine hoist that rarely gets used (hasn't been used in the last 8 years...), but it seems that it is having problems holding. The arm slowly drops back down after you work really hard to pump it up. Well pumping it seems too easy compared to other jacks I have used.

I have tried to bleed the air out a few ways, and I have filled up the cylinder with hydraulic oil. I am not sure if I have been successful at getting all of the air out. I'm not sure if there is a bubble in the small pump piston from when it got turned upside down. I've tried opening up the release valve and pumping it like the manual says to get the air out.

http://www.ehow.com/how_7880063_refill-engine-hoist-hydraulic-cylinder.html

Is there something else I should try to get this to work?

Thanks


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## TigerNut (Dec 18, 2009)

Caps18 said:


> I am borrowing an engine hoist that rarely gets used (hasn't been used in the last 8 years...), but it seems that it is having problems holding. The arm slowly drops back down after you work really hard to pump it up. Well pumping it seems too easy compared to other jacks I have used.
> 
> I have tried to bleed the air out a few ways, and I have filled up the cylinder with hydraulic oil. I am not sure if I have been successful at getting all of the air out. I'm not sure if there is a bubble in the small pump piston from when it got turned upside down. I've tried opening up the release valve and pumping it like the manual says to get the air out.
> 
> ...


If the arm slowly drops then you may have a blown seal somewhere in addition to trapped air. But first, it can take quite a bit of effort to get the trapped air out. You might try tapping the cylinder (with a large screwdriver or a hammer handle) as you pump, in order to encourage the air to migrate.

Most engine hoists have a large mechanical advantage and it will take pretty much no effort to pump up the beam by itself. When I'm raising my hoist to take up chain slack I usually don't even put the lever handle on, I just wobble the end on the pump directly by hand. It's faster and it keeps me from smashing the handle into something


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## Woodsmith (Jun 5, 2008)

I would suggest bleeding and topping up the oil first as that is the easiest first step. Make sure the hydraulics are clean and the oil isn't taking any debris in with it.

If that doesn't make any difference then it is likely to need new seals.

In the meantime don't trust it to be safe in use as it could give up completely under load.


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## Caps18 (Jun 8, 2008)

Sadly, it looks like I might have to take the hydraulic jack apart to see what kind of seals it has. This was supposed to be a simple thing.


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## Coley (Jul 26, 2007)

If you are borrowing it, don't take it apart, take it BACK!


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## Caps18 (Jun 8, 2008)

We don't use it anymore at work so they won't want to fix it, and that still leaves me with the same problem of not being able to remove the engine block that is in the way.


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## Woodsmith (Jun 5, 2008)

If it belongs to work then I wouldn't try fixing it.




I would make them an offer for it at scrap value!
When I owned it then I would fix it!


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## dragonsgate (May 19, 2012)

It could be as simple as the pressure release screw but if it has set for eight years with out ever being used it is likely the fluid has thickened and the check valve is not seating. If no water has gotten inside causing rust it may be as simple as disassembling cleaning and reassemble.


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## onegreenev (May 18, 2012)

Go buy one.


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## dragonsgate (May 19, 2012)

onegreenev said:


> Go buy one.


That’s no fun and it kind of takes the “Y” out of DIY.


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## TigerNut (Dec 18, 2009)

That's the pragmatic answer. 
http://www.harborfreight.com/1-ton-capacity-foldable-shop-crane-93840.html

$200. You're going to spend a lot more than that on the other tools you will need before you're done (nevermind the cost of the EV components), and you WILL be removing and reinstalling the motor/transmission a couple of times. 

You might be able to rebuild your cylinder and pump, but it will take a long time and it will also require tools that you probably don't have right now.


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## onegreenev (May 18, 2012)

Dang, beat me to the punch. Yes the point of DIY is the fun factor but also the cost factor. Cost trumps fun. I'd bet it would not be much fun trying to rebuild only to find out you need to buy one anyway. 

Go buy one. It will be yours. No more borrowing. 

They do come in handy. 

Pete


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## dragonsgate (May 19, 2012)

$200. You're going to spend a lot more than that on the other tools you will need before you're done (nevermind the cost of the EV components), and you WILL be removing and reinstalling the motor/transmission a couple of times. 

You might be able to rebuild your cylinder and pump, but it will take a long time and it will also require tools that you probably don't have right now.[/QUOTE]

Valid points. However if Caps can finagle the cherry picker for free or next to nothing he should be able to tear the cylinder down and put it back together with the same tools that he should have on hand for working on the vehicle. The pump is quite simple and of the half dozen hydraulic jacks I have worked on most of the problem was dirt in the system and I reused the “O” rings. If time is of essence then the best bet is buy one. I wouldn’t be surprised if you don’t wind up having problems with the harbor freight lift.


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## Caps18 (Jun 8, 2008)

I did find that the screw that I believe is used to bleed the small cylinder pump had a rubber o-ring on it that was broken. So I replaced that. 

I also tightened the blots where the arm pivots. 

Now it will hold it's own weight up (the arm doesn't fall back down), but it still doesn't lift a heavy load. Or the engine block still weighs more than 750 lbs...


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## onegreenev (May 18, 2012)

750 lbs? Mine picks up 2 tons. Must be an old lift.


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## Caps18 (Jun 8, 2008)

It only goes up to 1500 if the arm is retracted. It's max is 750 if the arm is extended.

And yes, I wouldn't be surprised if it is from the 70s or 80s looking at the manual that came with it.


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## Duncan (Dec 8, 2008)

Get one of the cheap ones - mine came with a free engine build stand 

I could not buy the steel it is made of for the price! 

Extremely useful things I use my to move all sorts of things - 

the last task it had was to hold the back legs of a pig I was butchering

(I'm not skilled in this art and the joints are not ~ pretty - but they are delicious)


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