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Power Steering Suggestions PLEASE

69MyWay

Well-known member
Joined
Jul 3, 2001
Messages
4,364
Location
Auburndale, Florida
Corvette
1969 Killer Shark
Okay guys, kicked the 2002 Autox season off with a bang, and looking forward to much more this year.

In any event, last year I notice on the stock engine that the power steering would get awful weak and noisy by the end of a run and on the longer tracks, gone all together by the end (runs in excess of 60 seconds).

So, when I was changing the engine I drained, flushed, and filled the power steering with Valvoline Syntech fluid.

All kinds of ugly crud came out.

The car is equiped with a power steering cooler.

So, when I raced it on Sunday after the second run (40 second or less track) the pump was really whinning. I never lost power assist, but got gosh aweful noise coming up.

After it cooled down, it is quite as a mouse.

Any suggestions? The pump has over 150K miles on it as well as the rack. No leaks that I am aware of, and no other problems. No noise when I start it cold in the mornings.
 
sounds like a viscosity problem, and the pump vanes are maybe putting a grove into the pump ring. might want to check temp of fluid after your run or when this noise happens.
a pressure check would help too.
tom
 
Chris

Which one of your cars??!!!!

Now for whatever it's worth..the OLDER style
PS pumps(C-3) had a restrictor in the output side of them...maybe there is something akin to that in the C-4.

What RPM range are we at?


Mike
 
Are there any Kinks in the cooler lines?

Or any belt slippage?

Mike
 
Mike,

This is on the 90 model.

One interesting note is Nikki hit a dog with the car several years ago and put a banana shape to the power steering cooler. No kinks though. I was able to push it back into shape. It is a large tubed cooler, and nothing appears unusual.

As far as viscosity goes, what else could I try?

ie., different brand, or additive?

Would Type F ford trans fluid thicken things up?

Yes, it only acts up when it gets heated up on the race course. Never notice any problems otherwise. No belt slip that I am aware of. I even tossed the frisbee (no pun intended) to cut down on the rotating mass and possibility of over heating/slipping the belt on the water pump pulley during aggressive up and down acceleration. I thought it was burning a spot in the belt and making it slip. Nope, it wasnt.
 
Looking

In da book for Idea's
BRB
Mike
 
Lucas Oil

Chris,

I've run across the Lucas Oil products and they have a Power Steering Fluid that's supposedly awesome. I haven't tried it but have heard from many people that it, along with all of the other lucas products, get great results. If anyone else has used them or knows about their performance, I'd like to know what you think. Here's the link for the homepage, Lucas Oil
And this is the only site that I've found to purchase Lucas Oil online, GimmeLucas.com

Good Luck,
Anthony
 
On the side of the pump

There is a FLOW control valve you might want to remove it or open up the valving. Ah HAH

this is part of the discharge line fitting

So It's probably the same conceptually as a C-3 Pump.. the HIGHER the pressure the more restrictive it gets..

Will keep reading

Mike
 
Well without one on the bench

It's kinda tough..
( page 3B1B-2 93 shop manual)

There are 2 valving points.

Logical order.. Spring, 1st valve, 2nd valve out to rack

( This is all theory at this point)

It lools like the spring keeps the two valves at a certian distance apart.. but lets two holes line up at low speed ( which is your pump discharge) but as the revs get higher It might press the valves closer to restrict flow and keep pressure down internal of the rack so you don't blow seals.

The holes are about the same size as a lifter oil hole and I'll bet there are 2 holes.

The valve fitting is on the discharge line so remove the hose ( hard line ) from the pump
remove the fitting on the side of the pump
and take a look.

Mike

So check it out...
 
One word. Foam. If you could stop on the course and look in the reservoir when the whining is happening you would find that a large amount of the fluid has turned to foam. The hard usage and high pressures of the fluid being forced through the valves ect. causes it to foam during competition. The pump is whining because it is pumping air (cavitation). The foam returns to liqued again shortly after the high demand stops.

I'm not sure what the C4 pump looks like but if it mounts directly to the reservoir like the older GM pumps there were some larger reservoirs on trucks, if you have the room. If it has a remote reservoir then you might consider building a new one with a large capacity. Maybe even a gallon so it would always draw clear fluid from the bottom of the tank while the foam would stay on top.

On the older type a remote tank with a line going to a fitting on the reservoir cap and the return line moved to the remote tank would work. I would follow up on the fluid question too. There has to be a better product out there. I remember back when I used to get involved with this stuff that guys were doing mods to their pumps but I don't remember what. I only had solid axles and manual steering mid years.

Tom
 
I think there are three great ideas here. First, look for a better quality fluid (Lucas), second, check out my pump and see if the valve is getting stuck during the high RPM and high pressure vaults, then not dropping back, so it is getting way too low pressure when my revs are normal, thus making noise and being hard to steer.

Finally, I have been suspect of foaming. The C4 has a resevoir tank but it is not very large. I will have to see what the C4 road race guys use.


Alright, three great leads to check up on. I think this problem is almost sovled.

:beer
 
I'll bet you work your power steering harder in a tight autocross course than a road racer does. Check out the reservoir in the power steering kit sold by Performance Bodies www.PerformanceBodies.com . The KRC pump might be worth looking at too. Only 2.7 lbs and operates 70 degrees cooler than any other pump, so they say.They use them on Monte Carlo and Grand Prix size dirt track cars. You know they get a workout far worse than you would give them.

I wonder what they recommend for p/s fluid?
Tom
 
Lucas Oil

I used Lucas when 78 had a horrible ps leak. With Lucas Oil (ps fluid), I could go for 7-10 days before refilling the pump. Without Lucas Oil...3 days, maximum!
ps finally failed completely just before our move to GA, when we arrived in GA I finished ordering the parts I needed to replace the entire system and had it installed. Haven't needed Lucas, we don't drive 78 hard at all, but it saved me a good bit on ps fluid for the several months I was waiting for parts!
Heidi
 
I left an e-mail inquiry with Performance Bodies to see if there is any direct fit application.
 
Check the hoses at the P/S resivor I have seen loose hoses that did not leak but let air in and that is what it sounds like. If you have the original band type clamps you may want to try the aircraft type also if when removing the hoses from the resivor you see any problems with the hose surface replace the resivor. But it does sound like it's getting air in it you do need to check the hoses and connections. Also has the car had the P/S hoses updated? There is a bulletin, about P/S drown noise and depending on VIN number and P/S cooler you would replace different parts check bulletins 90-3-138 and 90-376-3B if you have problems finding a copy of these just give me you VIN number and syspension RPO number and I'll look it up for you.

David Fulcher
 
OK here is the scope, it's not an easy bulletin to understand which car get's what but here goes.

you would need a to replace the pressure inlet hose with the longer hose with a cable in it to tune it it's about twice as long and goes out past ther sway bar before hooking back to the ract the original on is much shorter, P/N 260271771

if you don't have a finned P/S cooler you would need to install one and the P/N is 26027162 cooler, P/N 11508600 4 screws

some cars would have required a steering rack but yours is not one of them. Can't say that this would help the problem you are having but it is good to know you have the best parts to start with I would still take a good look at your P/S resivor hoses and clamps.

David Fulcher
 
Thanks a million.

I will be right on top of this and sort it out before the next event on March 3!
 
Two added points:
That restrictor in the pump outlet is necessary; if you open it up or remove it, you'll get overheating of the p/s fluid.

And as suggested elsewhere, the pump whine is undoubtedly due to fluid foaming and pump cavitation, quite possibly due to something as simple as a bad return (low-pressure) p/s hose. I'd check that first. Bad hose will look just fine, but will collapse under heavy usage, restricting fluid return to the pump.
 
Quick update

Went racing again this weekend on a much larger track (double the track time needed to complete), and warmer outside temps. We decided to go last minute on Friday night, so I had not had time to really dig into the things we discussed here. I did top off the resevior (over filled it a tad by accident).

It worked perfect on Saturday. No noise, no bind, no extra pressure. It did puke out a little bit of the over full fluid.

Now I am really baffled, (but pleased) as I had planned on really fighting the steering by the end of the track. Not to mention, we had three full slolom runs as well as many 90 degree turns.

So, I won't complain for now. I do need to wash the spilled fluid off.

Then again, maybe it was a little low before, by overfilling it and it puking, maybe it has balanced out????



***Oops!**** I posted this message under Nikki's log in. I am sure you guys figured that out by now.

Chris
 

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