ps whine all new parts

[ccapital83]

2004 3400 alero changed out both lines and pump all new oem parts still whines even at idle. 100% sure there is no air in it. flushed out all fluid twice added new fluid. have tried every fluid on the market. only fluid the helped with noise was lucas. but its still noisey. there has to be a answer to this mystery. 2 dealers were shocked and could not get it to go away tried everything they could. again its new fluid new hoses new pump all oem. there was to be a reason. again its not air what else is left?

 

[JimPghPA]

Have you used a mechanics stethoscope (while someone turns the wheel with the engine running), to pin point where the noise is coming from? If you have to do it while it is up on a rack.

 

[JimPghPA]

You can get a mechanics stethoscope at Harbor-Freight for a few bucks.

 

[JosephHarmon]

There is a supply flow problem. A return side flow blockage of some sort is happening.

Have ALL the rubber hoses been replaced?
A hose can have an inner liner ply breach that will separate & block or restrict.

There is a restrictor at the reservior hose end.
It could be incorrect have debries blocking or if it's missing or too large it could cause turbulence disrupt the reservoir supply.

There could be a problem with the relief valve, incorrect spring load that bypasses at too low a psi, maybe just a internal seal.
Just because the pump is new is no guarranty it's good.

Some GM's have a filter in route to the cooler. I don't see a cooler here.

http://parts.nalleygmc.com/showAssembly....key_trimLevel=0

 

[JosephHarmon]

Originally Posted By: JimPghPA
You can get a mechanics stethoscope at Harbor-Freight for a few bucks.


We already know the pump starves & whines.
Oil flow resistance would be a way as it will heat a a restricted area quickly

A temp gun or touch may be enough to locate a hot spot on a cold system.

 

[Trav]

Was the noise there before you changed the pump or did you install a new pump in the hopes of curing the noise?

 

[demarpaint]

How the rack?

 

[ccapital83]

i shoulda put the whole story down............... has a leaking return line reaplced it was fast and easy then instantly a whine. went to dealer said you just didnt bleed it enough. then 3 hours later they said its not air its a bad line so 4 hours later new line same whine. then they said ok its probably a bad pressure line next day new pressure line so a total of 2 return lines tried and one pressure line tried. still whining. and yes CAR NEVER MADE A PEEP BEFORE THIS. so then they said has to be a bad pump. tried a new pump whine got worse. tried 2 more pumps from dealer no improvement. so i found a brand new oem pump instead of remanufactured. had my private mechanic replace new pump asked him to check everything. new pumo was on still whining. so i was like [censored] everything is new 3 new pumps 2 sets of lines whats going on. the only thing that made it quiter is lucas ps additive which is soooooo thick im sure its terrible for car but it help a little with noise. and wierdest part is th steering is nice smooth like when it was new but the noise is so annoying everytime someone gets in car they notice it. i dont get it.

 

[Trav]

Quote:
has a leaking return line reaplced it was fast and easy then instantly a whine

I am almost 100% sure there is air in there, I've seen this before on this engine.

GM has a bleed procedure but even after doing this i had to pump the system under vacuum overnight to rid it of air.
this was a 3400 in a Venture van.

GM’s Recommended Bleeding Procedure:
1) Ignition switch off.
2) Turn steering wheel full left.
3) Fill fluid reservoir to Full Cold level. Leave
cap off.
4) Raise front wheels off ground.
5) With assistant checking fluid level and
condition, turn steering wheel lock to lock
at least 20 times. Engine remains off.
a) On systems with long return lines or
fluid coolers, turn steering wheel lock
to lock at least 40 times.
b) Trapped air may cause fluid to
overflow. Thoroughly clean any
spilled fluid to allow for leak check.
c) Keep fluid level at Full Cold.
6) While turning wheel, check fluid
constantly.
a) No bubbles are allowed.
b) If bubbles appear, recheck connections.
Repeat step 5.
7) Start engine. With engine idling, maintain
fluid level. Reinstall cap.
8) Return wheels to center position. Lower
front wheels to ground.
9) Keep engine running for two minutes.
10) Turn steering wheel in both directions.

 

[ccapital83]

i wish we literally did that not 20 times about 300 times no exaggeration!!!!

 

[ccapital83]

went out and did it for an hour got alot of air bubbles eventually none came up so we stopped. whine is still there its driving me nuts. this might be a long shot but any chance the cap gasket is no good letting air in?

 

[JosephHarmon]

There is air above the reservoir level normally.

The cap may be vented, it's sealed to keep the oil in- not the air out.

This is incredible bad luck.

 

[JosephHarmon]

You have to get the air bubbles out of the oil before you can get the oil level correct.

You get a snowball effect with air bubbled oil it can whip up and expand more.

 

[Trav]

You may need to vacuum this system down.
You need to buy a replacement cap at AA or AZ from the HELP section or a used one.

Instructions..
One the replacement cap cut the dipstick off with a Dremel tool.
Get a small 1/4 fitting, barbed on one end and threaded on the other with a nut and rubber washers to seal it.

Drill a hole for the fitting through the cap and install the fitting in the cap.
Attach a mityvac pump to the fitting and start the engine, make sure the fluid level is about mid level you don't want to suck fluid into the vac pump.
bring about 15 psi and run it 10-15 min, turn the engine off.

Pump the vacuum up to maximum and leave it a few hours checking the vacuum is holding. Vacuum will drop every time an air bubble comes up.
Normally a big rubber stopper with a plastic pipe through it works great but on this reservoir the cap uses 2 "ears" on the cap and the stopper wont seal properly.

 

[ccapital83]

you really think its still air in there? i checked i dont see any leaks anywhere. i mean if you think that will work ill literally go buy that right now and do it everyday until the whine is gone.

 

[SteveSRT8]

If you get air in the rack it can take a while to come out.

I've had a truck whine for a day or two but usually after a few heat cycles everything quiets down.

 

[[RT] ProjUltraZ]

maybe take it out and rev it high in low gears while working the wheel...* the pump is linear w/ rpm


*like a big open area not public roads

 

[ccapital83]

few days? this repair was done 8 months ago. whine hasnt stopped gotten worse or better since then. last night did seem to help very minimally and there was a ton of air bubbles when we did it. but my friend says it naturally bleeds itself over time so 8 months woulda took care of it so idk what to believe.

 

[mechanicx]

You got some good replies. It seems you are saying air bubbles keep showing up every time you bleed, right? It seems you may be are drawing in air despite new hoses and pump. You can draw in air without leaking fluid out. As was mentioned the mightyvac connected a reservoir cap adapter to check for vacuum loss is the test to see if the system is air tight.

It's possible your cap could be to blame. I think it suppose to keep the system pressurized when hot. This keeps air from entering the sytstem one way or another. Have you replaced the cap? Do you hear air rushing out when you take the cap off after ran hot?

Power steering systems can act funny. Some of them leak all over the place yet don't whine or get air inside, while other's appear sealed tight but whine and have air inside.

Again a vacuum adapter test would help pinpoint the problem. You probaby should look over all the hose connections and hose routing as the diagram posted earlier shows. I'm not sure how one could mess up the instalation but if all the clamps and routing is not correct an improperly supported and misrouted hose touching the body can transmit noise. But it seems your problem is air being drawn in somewhere.

 

[Trav]

Quote:
you really think its still air in there?

Yes i do. I had a Venture do this on me and it drove me crazy, new pump lines and rack and it sounded like a WWII air raid siren.
I don't know if its the design or the length/shape or routing of the lines but air gets trapped and wont come out, it will not self bleed.

When you make the setup i mentioned just make sure its good and tight and will hold a vacuum, it will get the air out.

I found this after i fiddled around a few days and got the air out, its similar to what i did only my cap mod seems to hold vacuum better, you don't need pliers to hold the vacuum and wait a few hours not 5 min making sure it is still under vacuum.