Power Steering Pump

edcourter

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Dec 19, 2016
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The power steering pump on my Mercruiser 86 350 may, or may not, have the correct power steering pump cap. I have two questions?

1; There is no dip tube so can anyone give me the correct cold fluid level from cap rim to top of fluid?
2: There is no vent of any kind in the cap, so where does the system expansion go?

It does work but sometimes the fluid is low, shaft and reservoir seals not leaking. Rest of system looks good but fluid is going somewhere? Bilge fair. Thanks
 

alldodge

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1. Don't know the distance, but my guess is the dip tube broke off. Just put it half way up the neck of buy another. Take the one you have to the local auto store and see if ones sold on the rack will work. Other wise its item 2
http://www.mercruiserparts.com/bam/subassembly/31739/1077/340

2. If it looks like a small radiator cap then it probably still works, if not, would need another
 

edcourter

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Dec 19, 2016
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es anyone with an 80's V8 Mercruiser know, or can check if their PS cap is vented?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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its a saginaw power steering pump, supplied by GM. the cap is plastic with a built-in dipstick. the rubber flap that seals the cap to the top of the can is also the vent. once you have proper fluid level, there really isnt a need to vent it..

https://www.google.com/search?q=sag...l4PZAhXFtlkKHeM7AwcQ_AUICygC&biw=1302&bih=910

the good news.... the pump can be rebuilt for $11. yes, the rebuild kit for a saginaw "can-o-ham" pump is under $11
 

Bondo

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Ayuh,.... The oil level needs to be 'bout 2" to 2, 1/2" below the top,...
Any cap from any saginaw P/S pump will work,....
The caps are fairly loose fittin', 'n vent themselves,....

If yer loosin' oil, 'n there's no leak into the bilge,....
Chances are the P/S Cooler freeze cracked, 'n is allowin' the oil into the motor's coolin' water,....
 

edcourter

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Dec 19, 2016
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35
  • I picked up a Doorman replacement, and it had a small vent groove bypassing the gasket. The filler hot line was just below the filler neck bottom.

    The seals, if good might take the hot level pressure but why would you risk it. Of course, everything Marine is different and the replacement cap could be wrong? I'll know in June, Thanks All



  • Post Note: When tightening the Power Steering belt, be aware that the tank body is medium gauge sheet metal. Prying between the engine and this tank will distort the front iron pump seal.
 

alldodge

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The tank should have no pressure at all in it, so the gasket is to keep dust/dirt out
 
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