How effective Is the power steering on the "H" series trucks

[greywuuf]

I just spent all day cracking lines and lifting the front off the ground on my beat old H70 and bled and filled and excersized and fiddled with the power steering and the best it seems to do is makes it "possible" to turn the wheels while sitting still. Like both hands pulling hard ...but at least possible......do I still have issues?

[C10 - C90 Bill]

Turning the wheels while sitting still is something I personally would never do, but if you are driving it and it pretty much feels like semi-power steering, I would say that would be pretty normal. My '71 9500 had great steering. Power enough to help you along, but not so much that you couldn't feel the road. Same with my '67 7500 as well.

[greywuuf]

Hmmm, having never driven a semi.....I don't guess that helps me much, and until I get a few other things fixed and replaced I won't have it on the road.....So I dunno. I guess I will have to wait and see.

[rkn463]

Check to make sure that the steering knuckles turn freely on the kingpins. We bought a farm tractor that had been sitting for years, thought the hydraulic steering had gone bad but it turned out the kingpins were dry and seized.

-Richard

[greywuuf]

Thank you Richard, great advice but not the problem in this case......had it up on jacks and everything moves free and easy.

[68 CRACKERBOX]

it should steer easy setting still if everything is working right.like with one hand.they have a real good power steering on them.

[greywuuf]

Originally Posted by 68 CRACKERBOX

it should steer easy setting still if everything is working right.like with one hand.they have a real good power steering on them.

Dang it!, well no. Good......I mean crap I have work to do.
Thank you for the response....

[jdl71]

Originally Posted by greywuuf

Hmmm, having never driven a semi.....I don't guess that helps me much, and until I get a few other things fixed and replaced I won't have it on the road.....So I dunno. I guess I will have to wait and see.

I don't think he meant semi as in semi-tractor, rather semi as in sort of.

[C10 - C90 Bill]

Originally Posted by jdl71

I don't think he meant semi as in semi-tractor, rather semi as in sort of.

That would be correct.

[greywuuf]

Hmmm, ok well it drives down the road kinda all right even before I serviced and bled the steering, however I can't steer it well enough to get out of the driveway. I litteraly thought something had locked up....it wasn't it is just so incredably hard to turn the wheels that is is dangerous ...unless you are rolling....and then because it is like forty eleventh seven turns lock to lock you have three point (or more) even standard intersections.

[rkn463]

Originally Posted by greywuuf

Hmmm, ok well it drives down the road kinda all right even before I serviced and bled the steering, however I can't steer it well enough to get out of the driveway. I litteraly thought something had locked up....it wasn't it is just so incredably hard to turn the wheels that is is dangerous ...unless you are rolling....and then because it is like forty eleventh seven turns lock to lock you have three point (or more) even standard intersections.

That just doesn't sound right - keep in mind I've never even seen one up close...

What I do know is that the FSM that I have for my 89 donor truck has specific tests that will diagnose if the pump is good and if the steering box is working right. Note the tests require a high pressure gauge made for testing hydraulic pressure. My manual doesn't cover the H series but the takeaway here is that a factory service manual is an invaluable tool. May be a total booger to find one for your truck. (Booger wasn't my first choice of words )

-Richard

[greywuuf]

Pretty sure I don't need a FSM for this.....it is a fairly simple hydraulic system. It would be handy to know what pressure the system operates at .....but if it is a pressure problem it is because it is WAY low.....like nearly zero. It appears to be a fairly standard vane style PS steering pump and has been left dry and operated that way enough times that it is likely just shot.

[rkn463]

Originally Posted by greywuuf

Pretty sure I don't need a FSM for this.....it is a fairly simple hydraulic system. It would be handy to know what pressure the system operates at .....but if it is a pressure problem it is because it is WAY low.....like nearly zero. It appears to be a fairly standard vane style PS steering pump and has been left dry and operated that way enough times that it is likely just shot.

What I liked about the FSM was that it listed pressure as well as how to diagnose a gear box with an internal leak. I expect at you are right about the pump if it was run dry. You may want to put an inline filter in the low pressure side of the system. If the pump was run dry and ground up inside I would be worried about metal shavings being circulated through the gear box.

Let us know what you find.

-Richard

[greywuuf]

Pulled the high pressure line off of the steering gear and fired it up....no flow .. so the pump is either clear dead of blocked (if it was blocked it means it is near dead anyway as I can not imagine blocking 1000psi hydraulic line)