Wide Power Steering PUmp Seal?
Thread Starter
Race Director
Joined: Jul 2004
Posts: 12,706
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From: Scottsdale Arizona
Wide Power Steering Pump Seal?
Since I'm sick of the constant drip of power steering fluid on my driveway, I finally pulled the pump out on Saturday for a quick rebuild. It works fine so I'm just doing the seals, particularly the large one that seals the pump to the reservoir. As I understand it, the later Saginaw pumps used a wide seal and these pumps had an X stamped on the pump housing. Mine does not have the X, but the seal sure looks very square rather than the o-ring that came in the kit that I bought. Please have a look at the pics and let me know if I have a wide front seal and if I can buy just that seal anywhere.
Last edited by CA-Legal-Vette; Sep 2, 2012 at 01:39 PM.
Melting Slicks
Joined: Oct 2005
Posts: 2,056
Likes: 8
From: Redruth Cornwall
Mike,
I have no idea but is it possible you have the earlier pump with a later seal thus causing the drip?
Would the o ring seal in the kit fit ( have you had it apart yet? ) or is it obvious it needs the larger seal?
All the best to you and the family!
I have no idea but is it possible you have the earlier pump with a later seal thus causing the drip?
Would the o ring seal in the kit fit ( have you had it apart yet? ) or is it obvious it needs the larger seal?
All the best to you and the family!
Thread Starter
Race Director
Joined: Jul 2004
Posts: 12,706
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From: Scottsdale Arizona
I did put the o-ring seal on there and it fits fairly well. As you said, it could be many permutations and combinations. It seems to be sealing so far. The seals were new enough to still be flexible except for the large pump seal. It could have been squared off by time and heat but it's very hard to say.
I've got a run scheduled for tomorrow so I suppose that I'll find out the hard way. I bought a gallon container of PS fluid just in case
Le Mans Master
Joined: Jul 2000
Posts: 6,001
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From: Saginaw Michigan
The pump housing to pump reservoir o-ring is a low pressure seal. Saginaw actually specified a material for that seal that actually had a controlled swell from contact with power steering fluid over time. So the o-ring would actually swell, fill the housing groove more completely, and seal better with age. That is probably why the seal in your pictures actually looks like it has a rectangular shape. It started out circular and ended up rectangular.
If it was an original o-ring seal, I would say it contained fluid in the pump reservoir pretty well for some +/- 35 years.
There are seals on the rear side of the pump. They are located in grooves in the pump housing where the studs press against the reservoir. Somewhere I seem to recall that the seals started out as o-rings and were changed to square cut seals as a cost saving measure sometime in the 1980s. It is possible that the grooves in the housing were modified when the o-rings were replaced by the square cut rings.
Jim
If it was an original o-ring seal, I would say it contained fluid in the pump reservoir pretty well for some +/- 35 years.
There are seals on the rear side of the pump. They are located in grooves in the pump housing where the studs press against the reservoir. Somewhere I seem to recall that the seals started out as o-rings and were changed to square cut seals as a cost saving measure sometime in the 1980s. It is possible that the grooves in the housing were modified when the o-rings were replaced by the square cut rings.
Jim
Thread Starter
Race Director
Joined: Jul 2004
Posts: 12,706
Likes: 329
From: Scottsdale Arizona
The pump housing to pump reservoir o-ring is a low pressure seal. Saginaw actually specified a material for that seal that actually had a controlled swell from contact with power steering fluid over time. So the o-ring would actually swell, fill the housing groove more completely, and seal better with age. That is probably why the seal in your pictures actually looks like it has a rectangular shape. It started out circular and ended up rectangular.
Jim
Jim
The o-ring seems to be holding though I haven't put any miles on it yet. The seal that I had on there may have been original or it may have been replaced less than 5 years ago. One of the ongoing challenges on this car is that a lot of the previous work on it wasn't done properly. I'm never quite sure if I'm looking at a part that wasn't appropriate or has simply worn out after almost 40 years.
