Oil pump advice needed

[andyy]

I've just taken my oil pump apart - Griff 500 - and found that a previous owner has put a bolt on the end of the pressure relief valve spring.
I guess this is to make the spring 'longer' which I guess increases the pressure of something.
Why would someone do this ?? What fault are they likely to be covering up ?? And what should I do now !!!
I've never had any oil pressure problems and the pressure has always seemed normal
cheers Andy

[bluebottle]

My old pre-serp 500 had this too, it was apparently a factory fit item

[andyy]

Surely not !!!!!!
Even TVR couldnt be this shoddy - could they ??
What does the spring actually do and what effect would a stronger one have ?
cheers Andy

[spend]

andyy said:

What does the spring actually do and what effect would a stronger one have ?

In my understanding it prevents you blowing a gasket (oil seals) by limiting oil pressure.

A stronger spring (or preloaded by shortening) will allow oil pressure to get too high (if your pump can manage it) ~ seems like rear crank oil seal is the most likely to pop first.

IMHO cold thick oils / temps affect this, It seems the pressure at which this 'safety valve' opens needs to be matched to prevent damage to your oils seals, using thicker oils can result in higher pressures. It seems to have been a common area of 'tuning' but I would be very careful...

Dave

[bluebottle]

Andyy,

Heres a link to a thread i started several years ago (check the postings for the 27th onwards);

[url]www.pistonheads.com/gassing/topic.asp?t=125921&f=9&h=0&hw=oil+pressure+relief+valve[/url]

[tvr_nut]

[redacted]

[spend]

I think there is a fair bit of discussion on this subject from the early marques with the V8. I certainly read some useful (and some dross) background in the Wedge & S forums rather a while ago. If you are interested itmay be worth searching in thise forums.

Dave

[GriffOz]

Andyy

Here is a link to a US British V8 site with a modification to the pressure relief valve. As you've got it apart it would be worth considering. www.britishv8.org/Back-Issues/jan2006b.pdf It's on page 9.

GriffOz

[andyy]

Thanks for the advice guys
I'll probably go with the tadpole relief valve idea
Looks like the grub screw 'modification' was standard practice after all

Unbelievable !!!

[barreti]

GriffOz said:

Andyy

Here is a link to a US British V8 site with a modification to the pressure relief valve. www.britishv8.org/Back-Issues/jan2006b.pdf It's on page 9.

Blimey, that makes interesting reading. I'll be digging through some more of those.
It goes to show that for all the panic about TVR turning up its toes there are oodles of people out there who have been playing with our kit for years