Oil pressure relief valve

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Pete Boole
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Joined: Tue Apr 04, 2006 21:28
Model: Elite
Colour: Monaco White
Year: 1974
Location: Nottingham

Re: Oil pressure relief valve

Post by Pete Boole »

Yes - the valve seat comes out.

Pete

Zaphod
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Posts: 243
Joined: Mon Aug 23, 2021 21:38
Model: Excel SE
Colour: Blue
Year: 1990
Location: Uffington

Re: Oil pressure relief valve

Post by Zaphod »

Ok I have a new rotor and annulus, new spring for the pressure relief valve, new gaskets for the oil pump and olive for the pick-up pipe. The new spring was about two mm longer than the original,
Of all the things I have lost I think I miss my mind the most...

1952 MG TD
1957 MGA 1500
1959 Austin Healey Sprite
1975 MG Midget 1500
1990 Lotus Excel

Zaphod
Senior Poster
Posts: 243
Joined: Mon Aug 23, 2021 21:38
Model: Excel SE
Colour: Blue
Year: 1990
Location: Uffington

Re: Oil pressure relief valve

Post by Zaphod »

Last weekend I got round to taking the alternator mounting off and then the auxiliary shaft housing. Two things became quickly apparent, the first one was that the alternator mounting should have sealant between it and the aux housing on a rectangular opening, this had been applied but it seems when tightened up the clearance between it and the housing was too great and no seal was present, I don't know how much bearing this would have on oil delivery to the pump so it may be a red herring as there were no gushing oil leaks when running. The second thing that came to light was aside to the alternator bolts the rest of the bolts that hold the auxiliary housing on were not very tightly done up at all. After these were undone, I found that there was no gasket sealant used and some of the original gasket was still present on the mating surfaces. I shall post the photos I have as soon as the battery on the iPhone wakes up!
Of all the things I have lost I think I miss my mind the most...

1952 MG TD
1957 MGA 1500
1959 Austin Healey Sprite
1975 MG Midget 1500
1990 Lotus Excel

Zaphod
Senior Poster
Posts: 243
Joined: Mon Aug 23, 2021 21:38
Model: Excel SE
Colour: Blue
Year: 1990
Location: Uffington

Re: Oil pressure relief valve

Post by Zaphod »

OK some images!
The rear face of the alternator housing..
Image
the outer face of the aux housing that mates with the above..
Image
and the block side face of the aux housing
Image
and finally, the block showing some of the original gasket material still attached
Image
Of all the things I have lost I think I miss my mind the most...

1952 MG TD
1957 MGA 1500
1959 Austin Healey Sprite
1975 MG Midget 1500
1990 Lotus Excel

Zaphod
Senior Poster
Posts: 243
Joined: Mon Aug 23, 2021 21:38
Model: Excel SE
Colour: Blue
Year: 1990
Location: Uffington

Re: Oil pressure relief valve

Post by Zaphod »

Finally got round to modifying a bolt so I could fit a 17mm socket to the drill. I then span the pump on the engine, the battery on the drill was not up to spinning it for more than a few seconds at a time however the gauged read 20PSI after 3-4 5 second or less spins which is more than I have seen so far (10 max when I was running it prior) so it looks to have been improved dramatically with new pump gears, relief valve spring, gasket and tightening up the bolts. I shall however make a gasket for the underside of the alternator housing. Hopefully I will soon be good to start it and run it up to temperature and drive the thing round the yard!
Last edited by Zaphod on Thu Dec 08, 2022 21:23, edited 1 time in total.
Of all the things I have lost I think I miss my mind the most...

1952 MG TD
1957 MGA 1500
1959 Austin Healey Sprite
1975 MG Midget 1500
1990 Lotus Excel

Pete Boole
Senior Poster
Posts: 3722
Joined: Tue Apr 04, 2006 21:28
Model: Elite
Colour: Monaco White
Year: 1974
Location: Nottingham

Re: Oil pressure relief valve

Post by Pete Boole »

Great work on the pump! Will you measure the clearance between the alternator mount and auxiliary housing before choosing gasket thickness? As an alternative you could always remove some metal from the alternator mount "feet" and the little aluminium spacer, allowing the use of just gasket goo - as original. Perhaps you have a mix of parts that weren't originally assembled together?

Pete

Zaphod
Senior Poster
Posts: 243
Joined: Mon Aug 23, 2021 21:38
Model: Excel SE
Colour: Blue
Year: 1990
Location: Uffington

Re: Oil pressure relief valve

Post by Zaphod »

The clearance seems to be just over 0.010" I've got some 0.025" gasket material which should crush sufficiently to seal it up
Of all the things I have lost I think I miss my mind the most...

1952 MG TD
1957 MGA 1500
1959 Austin Healey Sprite
1975 MG Midget 1500
1990 Lotus Excel

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