sperkins

At Roebling Road yesterday a P/S failure forced me to leave early.

I'm not much of a diagnostic person so hopefully you guys can lead me in the right direction. It was a club event so the first 3 sessions were mostly a joke running about 6/10's until I could get signed off for a faster group.
Once I got up to speed with the faster group, the P/S started acting up about 10 minutes into the session. It started with the tightening/bumping feeling in the steering wheel in turn 3. I tried to make another lap, but it just got worse so I pulled in the paddock. I cruised the paddock for a bit to cool the brakes so I didn't immediately stop and pop the hood to see if the fluid was cooked. Once I did check the fluid, it was extremely hot.
I was hoping that it had just boiled over so I went out on track the next session (about an hour later), but it was just as bad as I entered turn 1 so I packed it up and came home.

This is the first time I've ever run a 295 tire (Hoosier) on the front and the steering was noticeably stiffer than when I run 275's up front.

So.....
1. Is the pump fried and needs to be replaced?
2. Will a fluid swap suffice?

GettReal

Happened to me too... I had the same clunky feeling, .. easy fix right? replaced pump and added a PS cooler... same kinda feeling was still there, the rack was gone

Z11409

After new pump and cooler,change fluid after each track day. or--
www.turnone-steering.com.

if you play,you gotta pay

Bill Dearborn

The problem can be caused by the pump or the rack. Check both for leaks. I have gone through several pumps and racks. First replace one then a few months later replace the other. Symptoms are pretty much the same. Although when the seal on the pump fails you usually notice the problem after a significant loss of fluid unless it is a major blow out where the fluid blows all over the bottom left side of the engine and into the left front wheel well.

Bill

Timz06

I never had a problem with the PS on my vette. On my camaro, I burned up two pumps, and then went with the turn one pump, fixed the problem. Roebling killed my pump both times, tough with the long sweepers.

Why didn't you just drive without it? That's what I did, it only get's interesting when it cuts on and off in the turns

flink

I'm wondering if an underdrive pulley would help extend the life
of the PS system by simply spinning the thing more slowly?

sperkins

That's exactly what it was doing.

GrantB

I've never had a problem on the tight, twisty tracks I drive my FRC on with 8-9 degrees caster. It does have the big Z51/Z06 cooler on it, as well as an underdrive pulley, and I only run 275 street tires.

Z06_BluByU

Is this typical for stock C5Z's or is this more symtomatic of running larger sticky tires?!?! i.e. if the car is stock will the stock pump and cooler setup suffice..

:

MySR71

Hello all,

A couple of weeks ago I called the guys at Turn One. I wrote an e-mail to a friend with some notes from my conversation with guys there. They were very helpful. The following is part of that e-mail. You might find parts of it useful. Hopefully I got the prices right and info right.

(I called them because my power steering pump on my C5Z06 makes noise when hot. Changing fluids to Redline synthetic didn't really help. I've only run street tires, ie, no A6's, R6's, NT01's, RA1's, etc.)

I am in no way associated with Turn One.
__________________


When we put high loads on our steering systems at the track, this increases the pressure/loads on the power steering pump. The power steering pump does have a bypass valve built into it if the pressure/loads become too large for it to handle. However, once the power steering pump starts activating that bypass valve, it won't last very long before the pump fails.

Turn One offers a couple of different pumps for our cars. One is their standard pump and the other is an upgraded pump designed for people who run big, fat, sticky front tires on the front of their cars (this is the one I ordered of course). It sounds to me like their upgraded pump is:

1) Designed to operate at higher pressure
2) Requires less horsepower to operate
3) Will reduce power steering fluid temps for guys like us around 20 degF

The upgraded pump costs a little more than there standard pump. I don't recall the exact number but it was around $50. The upgraded pump costs $275. They also offer pumps for us with AN fittings rather than the fittings our cars use when stock. And they have an aluminum pulley for $65 which has slots cut into the pulley disk which allow access to the pump mounting bolts. This allows the pump to be removed without taking the pulley off.

I asked if he felt we needed a larger power steering fluid cooler. He said he didn't really know, but the magic temp for power steering fluid is 275 degF. So what we should do is do some hot laps and then come in and measure the fluid temp. If it is under 275 degF, we're fine. If it is over, then we need a larger cooler. Because the cooler is on the return side of the power steering circuit, the fluid running through the cooler is on the order of 30 psi so we don't need any type of cooler which can tolerate high pressures. A regular engine oil cooler is fine.

They do indeed rebuild power steering racks.

varkwso

I would flush the system with a good synthetic - consider it a form of faith healing.

It can be the rack or PS as mentioned. I eventually replaced the FRC pump with a Turnone - it was my pump. Tim is now running the first Turnone pump (and pulley) I had in my 94 Z28 so they seem to last forever.

NemesisC5

I've seen quite a few threads on PS failures, is it this way at the beginning of the season every year? Feels like an omen for me to install a cooler and fresh synthetic.

sperkins

I'll give that a shot and follow the funky flush procedure outlined by GM. Jeff - do you think this was related somehow to the larger tire? I was running old scrub R6's if that makes a difference.

Oh yeah....I've never even sucked the old fluid out of the resevior so I guess I had it coming.

hamdog

I have a '98 with less that 40k miles with 245/40 street tires up front. My pump went after two HPDE events last year. Tried flushing the system and using synthetic fluid but it still failed after the 1st session. Replaced the pump with Turnone and no issues since.
I would replace the pump and not risk losing a day or potentially a weekend at the track. It's a frustrating feeling to brake down not to mention the lost money in the registration, hotel etc.

fatbillybob

I think C5Z's already run a cooler for the PS. Has anyone thought about changing to a bigger reservoir and instead of having a pint of fluid up that to say a qt or 2? That will help the stock system run cooler too by having more fluid volume to throw off heat. Racers have tricked engines for years by doing remote oil filters and adding an extra filter which added a qt or more to the oil volume and that is worth a few degrees right there.

trackboss

I just removed my pump this weekend to send to turn one. Would have been a super simple job, but the retards at gm decided to mount the abs right in front of the pump with hard lines. I ended up removing the bracket and pushed the abs out of the way enough to get a pulley remover in there. I hate having to move the unit that much with hard lines. They could have at least used flex lines there for this purpose since they were set on moving it there from the back where it used to be on the early cars.
My question to those that have done this do you have any tricks to do this or do you do the same thing?

ghoffman

I had chronic P/S problems my C4. I had a hose blow, started a fire with the fluid on the headers (now I have a Halon fire extinguisher in all my cars)!, had the fluid boil out of the reservoir, and finally stopped when it got the proper factory P/S cooler.
With the C5Z, and now the C6Z, the factory cooler has been fine. The C5Z has never had a problem, and indeed Roy Benedetti has the C5Z now and got 3rd at Buttonwillow yesterday at an SCCA National. This is swinging new Hoosier A6's and running Royal Purple fluid with the factory p/s cooler. I have 35+ track days on the C6Z with no issues on Hoosier R6's. The point is, if you don't have the cooler, get it, if you do and still have problems make sure the basics are good before you get an aftermarket solution.

Z06_BluByU

stock C5Z with factory cooler. It hasn't been tracked.. I suppose it has the factory cooler.. just wondering if that will be enough if I ever decide to take it on the track..

beerkat

When my pump went out Varkwso suggest that I talk to the TurnOne folks. They said that it was most like my pump and not the rack. they said that the rack is pretty bullet proof. It is a pain in the butt to change the pump. Make sure your get their new pulley when you get the pump.

sperkins

I'm hoping I can convince the extended warranty company to let me put on the T1 pump if it needs replacing.