engine and drivetrain Oil Pressure Setback

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Update - Put pump back together, no obvious issues, when i went to fit the pump to the block i noticed this -

Flange that O ring sits against is approx 4mm below the pump mounting face

O Ring sits approx 6mm down the housing, so wont contact flange and create seal

The solution - add a second O ring, when i offered the pump up to the block i could now feel the O ring compress slightly as i pushed the pump home.

 

I then temporarily put the sump back on, filled with oil and cranked on and off for a good 2 minutes, removed the oil sender, cranked some more and then suddenly turned from a drip coming out to a solid gush - not shooting in the air but a decent flow. I then replaced the sender unit, cranked and the oil pressure light went out almost immediately

 

My concern now - is the 2 O Ring solution ok or a disaster waiting to happen, bear i mind this is an old engine and i suspect the damage due to weak oil pressure may have been done when last run by PO and i dont really want to remove timing covers because that will invariably lead to project creep which i cant afford at this stage.

 

I also tried to take a video of the oil coming out the spray bar - its not really spraying though - is that because its at cranking speed or do i still have a problem, you can just make out the oilflow towards the end of the clip

https://picasaweb.google.com/105528953083937093443/July252013_OilPump2#5904423591993993442

[TobyB]

As long as the 'bubble' in the tube sits FULLY into the oil pump (and it looks like it does) that should work-

the only real problem is when that bubble lets the o- ring extrude itself around the bubble, and then

air gets in there.

 

Given that it's an unknown motor, I'd run it- get an oil pressure gauge on it, and be careful not to let

the pressure get above 100psi when it's warming up.  Then I think you'll be fine.

 

I've had a suspicion that there are several specs for both pump recess depth and tube length over

the years, and that if you mix- and- match parts, you can run into problems there.  I have.

But I've never done a comprehensive survey of all the different parts that are available, and how well

(and poorly) they fit.

 

t

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Thanks Toby, yep i think it may be a mix and match engine, its a 1974 car (matching numbers) but its the old style pump, at what date did the change to the new pump take place? Anyway, i will try to sort out an oil pressure gauge for peace of mind.

[tim385]

I recon they changed it in 74 ...to the single nut type.Ive just pulled apart a 72 and that has a 3 bolt pump.But who really knows.

[TobyB]

Hmm, I was under the impression that the splined shaft was after the 2002 era, and when the later M10 went that way,

they just retro'ed the parts chain (heh) to reduce the stocking hassle.  And to make pump assembly easier,

as the flange is an extra part and operation to make.

 

But I haven't torn apart that many late motors. 

 

t