Author Topic: Power steering issue (Read 13125 times)

Cameron 77C3 · « **on:** October 28, 2006, 09:53:51 AM »

No it's not on my beast.

I have a mate who has a C4. He put it up on my hoist so he could change the old oil on the power steering. Drained it, ran the motor and moved steering from lock to lock to get as much fluid out as possible.

Filled her back up...and it groaned it's head off. He thought that it might be his pump as it was getting old so he decided to put the new one in. Same thing with the new pump.

Now there has got to be a trick here so what is it?

Chromie, any body.

Cam

[/align]

MADVET · « **Reply #1 on:** October 28, 2006, 10:23:16 AM »

Sounds like air in the system. Just turn the steering from lock to lock while keeping an eye on the fluid level, continue this until the sound goes away and bubbles stop frothing up in the reservoir.

Cameron 77C3 · « **Reply #2 on:** October 28, 2006, 12:41:34 PM »

Cavitation????

There was a lot of air in it as I could see the bubbles in the remote tank.

So how long does that take? He did do the lock to lock thing after filling. He drove home, about 20 minutes of winding road then next day to Yass but he said it was still noisy but getting a LITTLE quieter.

Is this normal on these beast? Is there no better or correct way to bleed the air off?

david_moore · « **Reply #3 on:** October 28, 2006, 02:51:15 PM »

Sorry I can't help here, am very interested to know more as the power steering in the '91 does howl its head off after 'spirited drivin'. And no, that does not mean after 'the four schooner handling' option has been purchased.
I have often wondered about the correct way to service the power steering on a C4. Wish i still had the '79.:22

Chromie · « **Reply #4 on:** October 28, 2006, 05:38:20 PM »

Yes cam madvette is correct
You have to run engine after each top up to the full mark of the power steering dip stick
Run engine while going from lock to lock on the steering
If pump is noisy after going from lock to lock shut down engine and check power steering oil level
and repeat this until level is at full
It is recommend that this be done with front wheels off the ground
The oil level should be checked again after 24 hours;-)

Chromie · « **Reply #5 on:** October 28, 2006, 05:40:07 PM »

If you have any power steering noise while engine s running and steering is not being used and the oil level is correct then the chances are that your pump is faulty
(exception is if you have just flushed the power steering oil out);27
Also some power steering pumps will be noisy if the oil is old, contaminated or incorrect type of oil used

Cameron 77C3 · « **Reply #6 on:** October 29, 2006, 03:50:55 PM »

So what your telling me it's a cow of a job and it takes time to get all the air out????

Chromie · « **Reply #7 on:** October 29, 2006, 07:51:37 PM »

No cam:b4
What I am saying is that it is a reasonably simple job based upon
1/ Equipment
2/ Experience
3/ Knowledge of the item you are servicing
4/ Some common sense
;42
And sometimes it can be messy when flushing out the power steering oil.:spook

Cameron 77C3 · « **Reply #8 on:** October 29, 2006, 08:10:53 PM »

Thanks Chromie.

We did all that, except the part of having the wheels off the ground. I'll pass it on and see what happens. It has to be a process thing as both pumps do it.

I have heard of additives that you can put in pumps to quieten them down. Any comments on these?

Chromie · « **Reply #9 on:** October 29, 2006, 08:40:10 PM »

Yes cam it could be a processing issue, but if both pumps do it then it maybe a mechanic issue especially if the first pump did not make any noises until after the oil flush.
The reason why the wheels are off the ground is to reduce strain on pump and steering linkages when going from lock to lock.
Also the true way to bleed power steering systems is to crank the engine over by starter motor until most of the air is out, but this puts too much strain on the starter motor especially old one's
So if you want to do it correctly, remove the spark plugs so the starter motor strain is reduced don't forget to remove the power wire from the distributor.
Sometimes power steering pumps will make a noise for a week after servicing/flushing/repairs depending upon mileage.
Hope this helps;-)

Cameron 77C3 · « **Reply #10 on:** October 29, 2006, 08:41:44 PM »

What about the additives that you can put in pumps to quieten them down. Any comments on these?

Chromie · « **Reply #11 on:** October 29, 2006, 08:52:46 PM »

Yes cam use them when you are thirsty
Doubt they will do any good but may do harm though
However if you might be changing the pump anyway due to noise what harm can it do
Just make sure that the pump is making the noise
Not the Air Pump, Water Pump or Alternator.;42

Cameron 77C3 · « **Reply #12 on:** October 29, 2006, 08:54:25 PM »

Funny bugger.;48

Thanks;42

Shane Finn · « **Reply #13 on:** October 30, 2006, 08:27:56 AM »

I have a similar problem on the '01 that I am about to attempt to sort out. I have never changed the PS fluid and it is now foaming which is apparently an indication of water contamination. The major problem is a serious groan in the pump after sustained high revs.

I have all the manuals for the car and reading the PS fluid flushing/bleed procedure they describe a process which uses a vacuum adapter on the reservoir to pull a vacuum on the system for 5 minutes to bleed the air.

I wonder if anyone actually follows this procedure? Would a steering specialist do this?

Chromie · « **Reply #14 on:** October 30, 2006, 10:44:52 AM »

yes zedohsix
The vacuum pump system is the best way to bleed power steering pumps
But no one has the vacuum pumps. So if you take it to a power steering place make sure that you make them show you the vacuum pump and watch them use it on your Corvette;42

Vette Obsessed · « **Reply #15 on:** October 30, 2006, 01:52:41 PM »

Hi guys, it's me who is having the power steering issues.

I suspect the aeration of the fluid is initially caused by the bleeding of the system (or improper method of doing it). The noise calms down after at least a day or two of driving.

This all started because the system ALWAYS gets loud when driving on curvy roads/tracks in a spirited fashion. I tried a few fluid flushes and different fluids to no avail - the groaning after filling the system is an additional issue to the "getting a steering pump groan when driving quickly on twisty roads".

The car has an oil cooler on the power steering and I am doubtful at this point that it is heat related (although I now have a cold air feed for the oil cooler now (thanks again for the help with that Cam ;42) I have not been able to test it conclusively yet).

The only time I haven't done this process with the wheels off the ground was at Cameron's although the noise has always been the same after filling the reservoir.

At this point I am thinking it is a pump or rack issue (the aerating fluid on twisty roads/racetrack issue that is).

Quote

Originally posted by david_moore
Sorry I can't help here, am very interested to know more as the power steering in the '91 does howl its head off after 'spirited drivin'. And no, that does not mean after 'the four schooner handling' option has been purchased.
I have often wondered about the correct way to service the power steering on a C4. Wish i still had the '79.:22

I'll let you all know when I get to the bottom of it David. I've had this issue since I got the car and am now committed to eliminating it. :24

After recent experience with an additive, I am inclined to say to avoid using them - whilst I think I used too much additive vs oil, I have just blown two lines on my power steering system in two consecutive days since using additive in the system (which is VERY thick).

Chromie · « **Reply #16 on:** October 30, 2006, 02:23:47 PM »

hi obsessed
If a pump makes a noise for a long period, no amount of flushing will cure it as the damage is already in the pump.;50
Rack will not cause a pump noise only a clunk, vibration or oil leaks.;37
What you need is a new/reconditioned pump.
As far as the additives are concerned ;51 with what you have stated.:v
Make sure that you allow plenty of time to fit the new pump
Prime the pump before fitting(put pump in oil and drive the shaft with a drill and see how the flow is (be prepaired for a mess as they pump large volumn of oil):spook
Read your hand book for correct oil type (I use TQ111):24

Chromie · « **Reply #17 on:** October 30, 2006, 02:27:54 PM »

Oh and special note
Always check your oil level with engine running
First check it cold and not running
Then hot and not running
Look at the level in the resivour make note of it's height then start the engine and look at the level again. Some if not most pumps should have the oil level checked while engine is running.
BE CAREFULL NOT TO TOUCH THE BELT OR ANY OTHER MOVING ENGINE PART.;28;34

david_moore · « **Reply #18 on:** October 30, 2006, 06:28:08 PM »

Great info chromie! I have done all that you have mentioned 'cept the vacuum stuff with steering specialists. I find it v difficult to find a mechanic that can be trusted and knows what they are talking about, but I am the original ultra cynic. I know they exist, but just not in my 'hood. Have had the pump at several specialists and am assurred it is quite ok. However, it still howls, groans and growls after 'sustained high revs' (ZEDohSIX).
I really think there is a problem with the pump, and from what you say, your info points to this. I am interested in how many others have this problem with their C4. Perchance is it particular year models of C4. A mismatch of steering rack to pump on lhd to rhd conversion?
Hey VO did you say your C4 has a cooler in the power steering system? I did put one on the ol'79 C3 but it was to stop the paint peelin off! well it stopped the odd leak anyway. But seriously, I thort the steering rack system was a lot more advanced, the power steering in the old 1983 commodore I have, beautiful.
As even a C4 corvette can really get movin, it would be nice to be sure about the steering, so many have told me it is ok, but I dunno..;49

Chromie · « **Reply #19 on:** October 30, 2006, 09:34:51 PM »

I find this power steering noise issue strange:b4
As I have not come accross this problem in my travels with vehicles and I have done a few Corvettes:grr
So my thoughts on this matter is as follows;49
Assuming things associated with the steering componets are fitted correctly.
1/ Heat interference ie exhaust too close to pipes (solution test line with a thermo gun and see how hot the oil is after a hard run) you may need to insulate the line from heat as an oil cooler may cool the oil too much and cause early failure.
2/ Faulty power steering lines/fittings/hoses (meaning dags/sharp objects inside the line causing airation or sharp bends/calapsed hoses causing restrictiuon)
3/ Poor quality oil/incorrect oil level.
Note all power steering pumps will make a noise when on full lock as this it the pressure relief valve dumping oil.
I probably have to say here but C4's and later should be done by someone with reasonable experience
C2's and earlier can be done by almost anyone (except ya wife;30) as these models are pretty much idiot proof;50