55.2-59 59 P/S CPP conversion

[dew468]

I have installed the CPP kit (400box) on my 59 with the original pump from the chevy. I spent hours with and with-out vacuum to bleed the system and seem to have all air out. sys still doesn't work, acts like no power at all. Is this pump powerful enough to runs the box or is pressure too low. I haven't found a pressure requirement for the 400 box anywhere. suggestions?

[mikebte]

Are you referring to the original power steering pump on the back side of the generator?

[dew468]

no this is the pump that came on the 327 from a 65 El Camino

[mikebte]

I would try and operate the steering with the front tires off the ground, a good back and forth should have it bleed good enough to work.
If no luck check your pump pressures and make sure the pump is working. I would think most power steering pumps that chevy offers would have enough to move the 400 box.

Mine is a 90s pump so I have no experience with the older pumps.

Someone else did have issues more recent. May look over his experiance and see if it is the same type of pump.
http://67-72chevytrucks.com/vboard/s...d.php?t=775413

[1project2many]

This article shows a 55-57 car conversion and does not mention changing pump pressure or flow.

https://www.classicchevy.com/assets/...evy/53-231.pdf

[dew468]

Thanks for the responses

[dsraven]

suspect the pump as the other post ended up being. if you have bled the system and there is no air in the system (little bubbles or a frothy looking fluid) then it would seem like the pump isn't working or possibly has a stuck open relief valve. lots of times the new or rebuilt pump has vanes that stick in their slots so the pump doesn't move fluid like it should. check to ensure the lines are connected properly as well. (to the correct ports on the box).

[dsraven]

check post 19 of the above mentioned thread, it has a diagram of what the vanes look like.
they should be out against the body of the pump to move the fluid correctly but a burr or a tight fitting vane could stick and cause low pressure from the pump. does the pump whine or is it quiet?

[mr48chev]

What are you using for power steering fluid? Automatic trans fluid while it functions doesn't work well in GM power steering. At least the older designs of Saginaw box and pump. If you have used that the best thing I can suggest is going to a GM dealer's parts counter and getting Genuine GM power steering fluid. When I worked in Pontiac dealer shops years ago I did all the power steering work and cured more than one makes noise power steering unit by flushing out the trans fluid and putting in the correct power steering fluid.

Front wheels off the ground/floor is a must when working the air out. Truth is I have never had one out of all that I had apart that I had trouble getting the air out of the system. That includes those that I had the box torn apart to the last recirculating ball.

Since the pump came off a donor rig it might be worth it to pull it off and check it out. Unless it sat for a long time without fluid in it or got hit hard on the end of the shaft there shouldn't be much problem. Being run dry is probably the hardest thing on the as the side plates get galled and don't seal well. I can write out step by step instructions for taking one apart and putting it back together if you need them. It isn't hard in the least but can be a bit tedious.

[dew468]

I've rebuilt many of these pumps myself. All vanes were de-burred and operate smooth. I don't have anymore air in the system and hoses are right. It can only be pump or box. The box is new but that really doesn't matter these days. Still trying to figure it out before the dynamite comes into play.

[dsraven]

when you hold it on the lock, turned hard one way, does the pump work at all? does the hose get pressured up and try to jump/move or straighten out some to be in a straight line under pressure and then when you let the steering wheel turn a bit the line slacks off some (the system will go to about 1500 psi so the hose will likely move if the pump is putting out)? if not it could be a poor pump or a bad relief valve. have you looked at the valve and possibly the fitting screwed into the valve to ensure everything is right?
here are a few links to some info. the first and second are videos explaining how to test the pressure in the system. the third explains how a power steering box works. the rest are just info on relief valves etc. hope it helps. its for a ford but most will work the same.

https://www.youtube.com/watch?v=h9rgkZ_R-Mc

https://benchworksteering.com/tech-t...-relief-valve/

https://www.youtube.com/watch?v=AeXj35aOK7k

http://www.gmtruckcentral.com/articl...rsteeringmods/

https://www.hotrod.com/articles/ccrp...ering-secrets/

http://www.corvette-restoration.com/...-pump-rebuild/

[dew468]

Thanks for the links. I have an old pump I'm gonna take bypass out of and modify like the article says and see what happens.

[dsraven]

is the old pump you have like the new pump? is it a known good pump? maybe swap it in and see if it fixes the problem?

[dew468]

The pump was working on the other car with no problem

[dsraven]

what about just swapping the pump then? you know it works already

[dew468]

The one on the truck is the good one I know works. I have an extra one I'm gonna pull the pressure valve from and try the modification on it.

[AZ59apacheguy]

Originally Posted by mikebte

I would try and operate the steering with the front tires off the ground, a good back and forth should have it bleed good enough to work.
If no luck check your pump pressures and make sure the pump is working. I would think most power steering pumps that chevy offers would have enough to move the 400 box.

Mine is a 90s pump so I have no experience with the older pumps.

Someone else did have issues more recent. May look over his experiance and see if it is the same type of pump.
http://67-72chevytrucks.com/vboard/s...d.php?t=775413

That was my truck. And it finally did work and it still does, but it starts to wine after a while. I am beginnin to think that the reconditioned pumps you buy from Rockauto, ebay or Amazon are junk. Not sure where to buy now......

[dew468]

I've rebuilt tons of these pumps, they are really simple to do. I'm thinking it might be a bad box. I'm gonna try the modified valve first before I go any further.

[tmoble]

if it's acting like no power assist at all, disconnect the pressure line at the box, point it into a large pan and start the engine. be ready to shut it off again quickly. See what it pumps. it's real easy to install the valve incorrectly. One popular deal is to install the o-ring in the wrong groove.

here it is properly installed:
https://www.speedwaymotors.com/Musta...-GPM,5852.html

this is the most common error with these hoses and pumps. Don't ask how I know this.

[1project2many]

Originally Posted by AZ59apacheguy

That was my truck. And it finally did work and it still does, but it starts to wine after a while. I am beginnin to think that the reconditioned pumps you buy from Rockauto, ebay or Amazon are junk. Not sure where to buy now......

Junkyard. 100,000 mile working OE pump is far more reliable than 0 mile crapshoot brand rebuild.

[dew468]

Originally Posted by tmoble

if it's acting like no power assist at all, disconnect the pressure line at the box, point it into a large pan and start the engine. be ready to shut it off again quickly. See what it pumps. it's real easy to install the valve incorrectly. One popular deal is to install the o-ring in the wrong groove.

here it is properly installed:
https://www.speedwaymotors.com/Musta...-GPM,5852.html

this is the most common error with these hoses and pumps. Don't ask how I know this.

Thanks for the info, I'm gonna check that and make sure.

[dew468]

Originally Posted by tmoble

if it's acting like no power assist at all, disconnect the pressure line at the box, point it into a large pan and start the engine. be ready to shut it off again quickly. See what it pumps. it's real easy to install the valve incorrectly. One popular deal is to install the o-ring in the wrong groove.

here it is properly installed:
https://www.speedwaymotors.com/Musta...-GPM,5852.html

this is the most common error with these hoses and pumps. Don't ask how I know this.

Thanks for the info, I'm gonna check that and make sure.

[dew468]

well it was a bad NEW box. CPP decided to replace it. should be here tomorrow.

[dew468]

got new box. now need health and dry weather to see if it's gonna work.