Author Topic: Power Steering Air Purge  (Read 2528 times)

Skitzerow

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Power Steering Air Purge
« on: July 26, 2007, 19:17:54 »
Well I did this fabulous job of rebuilding the engine.  Running fine.  But an hour or two into driving the car for the first time in a year I get a power steering leak which is keeping me off the road.

I took the pump out and separated the two halves of the housing and found the large oring cut, or torn.  It almost looked to thin to be the right o-ring. I also found there were only three of four housing bolts in place on the pump housing.  The fourth hole was painted. It looked like the bolt was missing from the start.  

There is a bolt head clearance problem in the upper right bolt area on the pump and another bolt that holds the steering pump bracket to the block.  The only way I got them both in was eliminating a lock washer on the forth pump bolt.

I put in new o-rings, put it all back together and no leak.  But air I got.  I tried a number of steps to purge the system.  But there must be an exact sequence to use.

Just when it seems like it is purged of air it comes back.  I took it on the road for half hour and then noticed when I turned left there was no power steering, but if I turned right there was. Wierd.

When I got back home I purged it again.  This time I opened up the bleeder screw on the steering shaft housing and let the bubbles come out on there own until only fluid started to come out.

I started up the car, attempted turn the wheel which shut locked up the unit and shut the engine right down instantly.

There must be a specific sequence to purge.  I tried to purge with a tube back into the resevoir by turning the wheel back and forth slowly until no more air came out.

Getting air into the system is not good on the O-rings because if high pressure air pushes past one spot on the o-ring it is like cutting it with a knife.

Anyone know?

Thanks
Scott


SDK

Benz Dr.

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Re: Power Steering Air Purge
« Reply #1 on: July 26, 2007, 21:39:48 »
I had a similar thing happen yesterday. First the power steering pulley fell off the other day ( which I fixed ) and then fluid started coming out of the cannister. The steering has been working perfectly for years so I figured that air was getting sucked in somehow.
I noticed a spot of ATF under the car after it sat over night but I coldn't find any leaks. It turned out to be the short hose between the canister and the pump. Not only was it kinked but it had a small crack in it. Fluid didn't leak out as there is no pressure at that area but air can easily get sucked in.

 I pulled the battery to get more room to work and removed the old hose then cut a new one to fit. After I filled the canister I moved the steering left and right several times to purge the trapped air in the system. When I starting the engine the fluid never bubbled or foamed at all and it was like there was never anything wrong.
Of course, the engine bay was a mess from all of that ATF spewing out everywhere. Got it cleaned up and now the car runs great.

Dan Caron's
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rwmastel

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Re: Power Steering Air Purge
« Reply #2 on: July 26, 2007, 22:13:46 »
Scott,

If you can't find any problem hoses like Dan did, then try these threads.

http://index.php?topic=4598
http://index.php?topic=4574
http://index.php?topic=4509
http://index.php?topic=2842

Rodd
Powell, Ohio, USA
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