OldS10

First off, I tried looking for another thread about this and couldn't find one.

We started with a 98 Vette LS1, put a rebuilt P.S. pump on it prior to installing it into the 89 S10. The S10 had NO power steering issues prior to the install. Upon startup, the pump has a groan. We tried to bleed the system, drove it a bit (to see if it would settle down), and after coming up with no solutions, figured it must be the pump, since it was the "new" item in the mix. Actually, it's not the only new item....the lines are new ss braided custom lines and the resevoir is new, custom built, as the Vette factory resevoir wouldn't fit in this application, but we didn't think that these other items should cause such a problem. The resevoir is still mounted above the pump, so as to gravity feed into the pump. The resevoir IS a bit smaller in capacity than the factory resevoir.
We changed the pump , again with a rebuilt pump. Still the same noise, which sometimes is very faint, until you turn the wheel. We also tried Lucas stop leak, as recommended by someone.

Also, the Vette had rack & pinion steering and the S10 has what I think is called a "recirculating ball" steering box. We even thought that there may be a compatibility issue between the two types of systems.

A friend is researching the issue from that angle, including the possibility of using a different fluid.

Any ideas?

At any rate, the truck is a lot more fun to drive than when I picked it up at the dealer in Jan 1989 (after waiting for 10 weeks) with it's original 4.3l.

Thanks!

mantycarguy

Just let the air bleed itself out by opening the resevoir after you run the engine. If the system indeed has air in it, running it only circulates fluid that is aerated already. After letting it sit for up to 24 hrs. look into the resevoir for any bubbles.If none are present you should be good to go.

OldS10

Took it for a 15 mile drive, shut it off, opened the resevoir. We'll see what tomorrow brings.
Thanks for the input!

OldS10

Still noisy the next day. A couple of days later, I called a company that rebuilds power steering pumps and asked for specs on the two pumps. The tech thought that the 89 S10 steering box would need more volume of fluid that the Vette rack & pinion. He suggested drilling out the orfice in the pressure output fitting on the Vette pump. He also thought that running the system that way (without a larger orfice) would burn up the pump. The first pump may have burned up, as the grease was coming out of the bearing and the fluid was getting pretty hot, too. I drilled out a spare fitting about .020" -.025" over (about 10-13% over stock). We'll see what that does. (The flow rate for the S10 pump is nearly 2 times that of the Vette, though the pressure is fairly close.)

Sarg

iTrader: (6)

Vette also has an inline cooler from the factory. I am doing something similar with vette accessories and while gathering some parts at the local chevy dealer I had them print out the ps system diagram. Wonder if that cooler is necessary?

OldS10

Interesting thought. We have the factory Vette manuals and I never even noticed the cooler. It seems that this shouldn't be rocket science, but we have looked down a number of avenues and still haven't solved the problem. The drilled out fitting didn't change anything either. We even changed the hose from the resevoir to the pump inlet, thinking that it may be sucking air into the system, but still no improvement. The pump is noisy and we still have foam in the fluid.

Sarg

iTrader: (6)

I am sure you could get a cheap inline cooler for $20 or so. Might be getting too hot and cavitating?

Steve01SS

iTrader: (43)

Not all C5's had a powersteering cooler. It came on Z51 suspension and Z06 cars. It's not very large. The cars without the cooler just had like a U shaped hardline where the cooler is on ones equipped. My car has one and my buddy's doesn't.. doesnt seem to make a difference really.

1981TA

iTrader: (7)

The S10 steering box requires less pressure thab the vette pump puts out, and the result is higher-than-designed for internal recirculation within the pump, and overheating. My recirculating ball-style box requires @800 pounds of pressure, with the vette pump puts out @1500. My cure? Buying a new Turn One pump. I'm pulling the trigger on the purchase tomorrow. I'll let you know if it fixes my squealing, groaning annoying pump problem.

OldS10

I look forward to your reply. Last week I checked the fluid temp with a touchless thermometer and read around 200 degrees, which I thought was high.
Yesterday I had another thought.....In looking at a Billet Specialties resevoir on Summit's website, I noticed that it said that it was vented & baffled to help prevent foaming. We fabricated our own resevoir (photo attached)and it is NOT vented.

oldngray

iTrader: (9)

I think 1981TA has your answer.. I just got my pump(05 vette) and JGC box back from Lee Manufacturing for a re-build and pump calibration as per the different pressure needs.......

drpepper

i second what these guys say. your orfice needs to be smaller instead of larger to stop the foaming. you can also add a smaller orfice. it's available from borgeson and several of the steering gear guys. just restricts the flow some to lower the pressure.

mantycarguy

Got this from somewhere here(maybe a sticky) Corvette pump was rated at 1250-1350 and 2.4-2.8gpm and truck pumps 1425-1525 and 3.0-3.5gpm. What you need to do is open up the orifice to allow for more flow through the gear(volume). You may also have to change the shim to up the pressure slightly. I would try to increase the volume without changing pressure as the pump max pressure is already approx. 88% at max of where it needs to be.

rpturbo

iTrader: (47)

I think there are a ton of us S10 swap guys out there who are having similar problems and looking for the solution, that's how I found this thread. I was trying to find out what the pressure and flow should be on these items, but was not finding it. I'll keep checking this thread out to see how it works out. I guess it's not just S10 guys, but also F-Body swaps too, since they are basically the same steering box.

bczee

iTrader: (12)

This subject has been posted a few times before.. as noted, the newer LSx pump have a much higher pressure than the older ones. Something in the area of 1,300-1,800 PSI as compared to some of the older pumps, which would be in the lower 800-1,200 PSI range.

You can use different pressure valves (inside the output port).

I had problems of lock up under power on my Chevelle. I then put on a F-body cooler and the lockup and noise went away.. so.. you will or might encounter two issue that you need to work on. 1) Higher pressure and 2) Heat !

Anytime air or fluild is under pressure, it will generate heat.. and this can cause problems.

also, to blead the system, jack the car up and place on jack stand (front only will do) and the front wheel in the air, start the engine. Bring the RPM up to a high idle (1000-1500), then turn the steering wheel from lock to lock a few time until the air is out of the system. (check the fluild to make sure it is at full).

Good luck.

BC

downset71

Bczee- when u say lockup do u mean like it drops out for a split second when turning? Because i have the 04 gto pump using an 87 IROC box in my monte. Sometimes i get the same issue

bczee

iTrader: (12)

Yeah...pretty much it had happened to me when I stepped on the accelerator.. the steering wheel would freeze for a moment, this would happen both while going straight and in a turn. I think the pressure and heat combined caused my problem and adding the cooler lessen the issue and was able to handle the pressure with the cooler temp of the fluild.

I helped a friend pu a new steering box in his 57 Chevy. Same pump just new 500 seires box.. it had the same problem, we where able to resolve his problems by trying different releif valve/spring in the pumps outlet.

BC

1981TA

iTrader: (7)

My Turn One PS Pump arrived yesterday. With luck it will be in by Sunday and I can give a report on my impressions.

downset71

Good info on trying a cooler. Thats my next step

OldS10

Thanks for all the input. I haven't ignored it, I've just been offline for about 3 weeks.

OK, here is the end result of OUR power steering problem.
We took the reservoir (tank), hoses, & pump to a guy in Denver that specializes in power steering systems. He put our components on his “test bench” and said that he thought that the reservoir was the problem.
In building our own reservoir, we neglected to bring the return fluid into the reservoir below the fluid level. This caused much agitation of the fluid, thus putting air into the fluid, causing the pump to cavitate. The solution was to redo the return inlet to the reservoir with a tube that ran down to the bottom of the tank (see photo), with multiple holes in the side of the tube (to better disperse the fluid in the tank). Upon start up, the power steering was quiet & works great!
During this process, I had talked to an engineer who worked for Saginaw for a number of years. He said that a fair amount of thought went into designing the reservoirs. He thought that we ought to use the original unit, but it wouldn’t fit. So if you have to build your own, put some thought & time into it.
The pump is back to the original orfice size (for the 98 Vette).
Time will tell if we need a cooler or some other changes. For now it works great. Even the feel of the steering is like it was before the engine swap.