oil pressure relief valves

[PAUL GOTTS]

After experiencing a stuck oil pressure relief valve for the second time in two years at Zolder recently (unfortunately coupled with the breakage of the distributor shaft drive to the oil pump gear) on my 4.3 Wedge, I can understand why some see this as something of a design fault. Heat seems to be a contributory factor in the steel valve sticking in its alloy housing. It may also be possible for a small piece of debris in the oil to have the same effect. Now I know that people like JE use a modded tadpole valve to overcome this potential seizure, but I remember at least one member of the national e-group warning me off using them the first time this happened to me, citing this as the cause of a wrecked engine. Does anyone have experience of the effectiveness or otherwise of these valves, or any other mod. to the housing itself to overcome this problem, as I'm now getting a bit paranoid.

Paul and a 400SE which has arrived back in UK today from the Zolder meeting, courtesy of the wonderful AA Five Star Recovery service - just under two weeks to cover 200 miles……….Won't be using them again.

[PAUL GOTTS]

quote:One and the same - we ran that car for 7 years, mostly as our only car - more reliable than the 4.3 but definitely not as much fun to drive or to listen to as the bigger wedge. Last time I replaced the pump cover, gears, valve etc. (with new parts) it was about £35.
Paul:
I rebuilt my 390s engine a few weeks ago and contemplated the pressure relief valve whilst it was stripped! I used a slipstone to take the sharp edges off the valve plunger and the casting, but there were some score marks in the housing where debris had obviously been swept around by the vanes. I couldn't work out whether the pump's internal mesh filter would be effective at keeping crud out of the relief valve though. I guess the only truly effective fix for a scored housing is a new one, but at 400-odd quid, I left mine on!
ONe other mod you can make to the valve is to fit an uprated spring from Rimmer Bro's et al, that's supposed to up the pressure by 10 psi. Worth every penny of the three quid they want!
Incidentally, are you the same Paul Gotts as featured (with 350i) in Autocar in August '92?! I have the article reprinted by Transport Source Books, and the name rang a bell... ;-)

Ian