100 oil pump

[Michael Oritt]

I'm a bit uncertain as to whether or not the 6-cylinder oil pump will fit a 100. My understanding is that it will NOT and since Moss lists different part no's. and has an N/A by the 100 I suspect the answer is NO.

Can someone please enlighten me and include, if known, a source for a new or reconditioned 100 oil pump.

 

[CraigC]

They are not the same and not interchangeable.
Try AH Spares, Ahead 4 Healeys, Denis Welch.
What is the problem you are experiencing? Have you already removed the pump and inspected it? Have you inspected the supply pipe?

 

[Michael Oritt]

Craig--

Thanks for confirming what I suspected.

A few months back I changed the oil and filter and had to back off the filter a couple of turns in order to get oil flowing, this despite having backfed oil into the pump via the OP line. That was a first and indicated to me that the pump was not being all that it could be. My oil pressure has been falling off over the last year and I am planning to remove the sump in the near future to inspect both the pump and the lower end. BTW yesterday's warm weather ride increased my concern: Oil pressure sat at just below 40 psi at cruising speeds and fell to 10 psi or so at idle. In better times pressure at 3K or so was 55 psi and it never fell below 25 at idle. I'll also remove and inspect the pressure relief valve but since pressure will go up to 55 with cold oil I don't think it is the culprit.

 

[Bob_Spidell]

Don't automatically rule out the gauge. My BJ8 showed nearly zero pressure at hot idle from the time I bought it--even after installing a new pump--until I had the gauge overhauled and calibrated--whamo, 15-20psi.

 

[Healey 100]

Mike:

My 100 has the same problem getting the pump going after a filter change. This started after I converted to a spin on filter. I suspect the problem with mine is with the filter conversion and not the oil pump. Never had an issue with the cannister filter. I like the spin on setup xcept for all the drama getting it going. It does fine once the filter finally fills up.

Suspect your falling oil pressure is just due to normal wear in the main bearings. As the clearance increases, it's harder to generate the expected 40+psi pressure. Mine runs at about 25-30 psi at speed when hot. I have been driving it for years that way, seems not to hurt anything.

 

[Michael Oritt]

Plastigauge will tell the tale...