Forklift help

[kwkracing]

I have a older clark forklift and the mast works perfect for lifting up and down, but it always leans forward as soon as you let go of the control lever.

If you pic up a load and you tilt it back, as soon as you let go of the lever it starts tilting forward till it extends the two cylinders all the way forward. It will tilt forward or backward perfectly, just as soon as you let go, gravity pulls on the mast and forward it comes.

Where do you think my fluid leak is, in the spool valve or in the tilt cylinders?

Thanks keith

[cepx111]

Is this a trick question? :wink:

I'm gonna go with the spool valve, if the cylinder was bleeding by that much, something tells me it wouldnt be working right at all but what do I know>Cp

[Harbone]

spool valve is hung open so it thinks you have the tilt lever forward all the time. might be a simple "take apart and clean" fix.

[kwkracing]

Do you know if the spool valve has some o rings or sealing rings on it? The mast does not fall forward, but after about 30 secs it has tilted all the way forward. Thanks again.

[Harbone]

depends on the forklift, some of them are not servicable and you have to replace the unit, some are seals and some are o-rings. the only way to find out is to dig into it. if its bleeding off slowly like you say, its probably a torn seal or oring. couls also be a piece of dirt caught in the valve...

[deward]

Okay, I have to ask; has this affected your 1/4 mile times? Is it faster with the forks tilted forward or tilted backward? LOL.

[TheRabbit]

If it still tilts back fine, it's probably in the valve or even the linkage sticking. Most the time the valve body is covered in a bunch of dirt so it's easy to hang up or get dirt in it. You could put a pressure guage on it to check it to be sure.
It could happen, but not common for both cylinders to go bad at the same time.
BTW I hate working on forklifts. You have to bend over almost all the time no matter what your doing to 'em.

And I think your 60' times will be faster with the forks tilted down. lol

[lively]

if you install AMC control valves it will go alot slower --but -- you probably have TOYOTA valves and they stick in foward all the time and you loose control :oops: :lol: :lol: :lol:

FORK LIFTS ARE A PAIN IN THE UUUUHUH AT TIMES

[kwkracing]

i actually just put a gm powersteering pump and a gm alternator on it. 8)

[lively]

i had a forklift i used that had been converted to the one wire alternator and POWER STEERING,TOO--IT MADE THINGS ALOT SIMPLER 8) 8)
alot easier when you needed to repair things :oops: :oops:

[Tod74]

I printed this and showed the maint guy at work that works on ours. He said the cylinders more likely than the spool valve

[rob41willys]

I've been a forklift mechanic for many years and it is probably the piston seal in one of the tilt cylinders. If you can cap off the cylinders individually just cap one side off and see if it bleeds down if not it is the other side

[kwkracing]

I have not had a chance to work on it, but im going to check the tilt cylinders. i assume it has two sets of seals inside since its dual acting? I replaced the seal in the main cylinder years ago, so should be similar?

[rob41willys]

It will have some type of seal on the piston depending on how old the forklift is and a seal on the gland end of the cylinder. Very easy to replace and can be done without even removing the cylinder from the machine.

[kwkracing]

its around a 60 model I will post a picture tonight.

Thanks

[kwkracing]

Clark it40

http://a.imageshack.us/img225/1272/img8824d.jpg

http://a.imageshack.us/img339/8016/img8823f.jpg

[lively]

NHRA CERTIFIED CAGE/FRONT AIRDAM/EXTRA TALL SIZE TIRES ON THE FRONT[RICER!!]/NICE OUTFIT---LET'S SEE--ABOUT A 3 MINUTE 1/4 MILE AT 9 MPH 8) 8)

[kwkracing]

You just made me laugh so much!!! Im going to laugh every time i look at the old forklift! Especially the nhra cert cage!

[lively]

IT might not look the purdiest-but--it will still get the job done 8)
hope you find the problem :wink: :wink:


THEN YOU CAN HOOK THE NITROUS UP :? :? :? :lol: :lol:

[kwkracing]

I have been using it for about 8 years and it always keeps going, just needs a little push every now and then. i finally got tired of the generator not charging and no power steering, so i took the factory stuff off and put a gm power steering pump and 3 wire gm alternator. Its ugly but works and makes me money.

http://a.imageshack.us/img51/9132/redjs.jpg

If anyone has a picture of what the cylinder looks like apart that would be awesome! Should the hydraulic shop have the seals for it, Is it common for them to be a stockable seal and not a special order thing? Its been about 5 years since i rebuilt the main cylinder and i really dont remeber doing anything but knocking that nut off the top, pulling the shaft, taking it to the hydraulic shop and they slid on a big seal and i put it back together. should be the same except it will have two seals on the double action tilt cylinder? Thanks so much

[lively]

NICE work on the ps and alt.--did you run a ram for the steering or change the hydraulic system to fit??

[kwkracing]

no, it used a saginaw steering box stock!!!! It has the steering box under the floor below the column and has a five foot steering arm going to the back. All i had to do was make a bracket and get a hydraulic hose made.

http://a.imageshack.us/img685/1034/carc.jpg

http://a.imageshack.us/img291/1189/car2aj.jpg

Sorry the pics are so small, but i thought you would get a laugh out them

[fla1976]

Just one thing,,, Where the hell are you going with my car?

[kwkracing]

about 3 miles, from your house to my shop. I decided to carry it down the street instead of loading it on the trailer.