Truck Repair k100 cab lift

treeline

Member
I have a 1980 k100 love it the best truck I ever drove. having a problem with the cab lift system. The right side goes up much faster then the left so much so that the body twists to the point I`m afraid the mounts will break. pistons are only one year old, pump is new, lines are good. thought I had a bad piston so I took them out switched them to see if the problem reversed but had the result. same issue on the same side. has anyone come across this problem?
 

Mike

Well-Known Member
Staff member
It's not binding or hanging on anything on the way up?

Has it sit for a long time without being lifted?
 

Mike

Well-Known Member
Staff member
Another thought. Are one of the cab locks not releasing (or releasing slower than the other)?
 

treeline

Member
there is only one cab lock, works fine, it`s not binding anywhere. system was working fine last fall sat through the winter
 

treeline

Member
I noticed on some posts that some systems have something called velocity fuses mine just has straight t fittings, but it worked fine up until now
 

treeline

Member
you guys are pretty much my last resort, tried everything I could think of, my only option seems to be to buy a whole new set up and start from scratch. but was hoping not to have to spend all that money to replace a system that`s basically brand new already. thanks for the help
 

Hammer166

Instigateur №166™
you guys are pretty much my last resort, tried everything I could think of, my only option seems to be to buy a whole new set up and start from scratch. but was hoping not to have to spend all that money to replace a system that`s basically brand new already. thanks for the help
So the cylinders are just teed together? Are you sure? Because if both cylinders have same pressure on them, the only explanation for a crooked cab is more load on one side than the other. Teed together cylinders are basically a pressurized water level.
 

Hammer166

Instigateur №166™
Another thought. Air in system on low side? If there's any type of flow division in the system, air can cause what's happening.
 

treeline

Member
yes just teed together, that`s why i thought I had a bad cylinder so I switched them from side to side but nothing changed, had the same issue. do you think velocity fuses would help? Can`t figure out why one side is getting more pressure than the other
 

treeline

Member
tried bleeding them doesn`t seem to be any air. might not be doing it wright though not sure how to bleed this system
 

r3gulator3

FLATBED GANGSTER
Supporter
If any kind of debris is stuck the velocity fuse of the side that won’t go up, can cause this.
 

treeline

Member
thanks but why would I still have the same problem on the same side after switching the cylinders? I think i`m going to scrap this whole set up and start over with all brand new everything. Can`t think of anything else to do
 

Sudmuriwai

New Member
As the cab goes forward the steering shaft has to extend. Check that it's not binding. You could also disconnect the steering shaft from the steering box and see if that makes a difference. Hope this helps
 

Ontario Outlaw

Hozer Witta Hood
Supporter
thanks for the help guys checked the steering shaft and that was it. it was binding freed it up and all is well. ol weezy is back to normal. Thanks again. I attached a few pics if anyone is interested
We love old iron, thanks for the pics!
 
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