Bent oil pressure relief spring!

[shoggyraminator]

Check this out. Went to replace my relief spring at the weekend and discovered it was bent!. Bit odd. On closer inspection you can see it has actually half snapped about three turns from the top, causing it to look bent. Glad I caught it before it went completely. 38K FYI.

[Gazzab]

Cant see the pics from here! But well done to find that and fix it.
My first cerb had a bit of broken spring rammed in with a new spring. Ultimately I had the engine rebuilt. :-(

[pikey]

Sorry, but did you manage to get 38,000 miles from one spring?

[shoggyraminator]

pikey said:

Sorry, but did you manage to get 38,000 miles from one spring?

As far as I can see this is the original spring. There is no mention of it ever being replaced before. I've only had the car for a shortish period and just getting round to doing the long list of check this/replace this before I start to use the car properly. My oil pressure always sat around 45 PSI which I felt was a bit low, especially when cold. Also the spring was around 2mm shorter than the new one. Not sure what the pressure is up to now as I aint started it since , for other reasons.

[bobbins]

Well spotted.

Mine snapped cleanly with just under 30k on the clock last year. Pressure always read low but much better now (rarely drops below 50 now).

[James]

I used to go through them like nobody's business. It was quite common for me to have to replace one at a track day. I used to be able to do one in no time flat (top tip, carry a 24mm spanner and a bag of spare springs).

There was a design flaw in the oil system on the AJP8. Under certain circumstances you can get resonance at the natural frequency of the relief spring, and that causes them to just go ping. I used to find that resonant frequency quite regularly on track

A combination of a slightly modified oil pipe and a thicker but shorter spring (to give it the same relief pressure) fixed the problem with mine, but not before I'd snapped about a dozen of the little blighters

[Gazzab]

shoggyraminator said:

pikey said:

Sorry, but did you manage to get 38,000 miles from one spring?

As far as I can see this is the original spring. There is no mention of it ever being replaced before. I've only had the car for a shortish period and just getting round to doing the long list of check this/replace this before I start to use the car properly. My oil pressure always sat around 45 PSI which I felt was a bit low, especially when cold. Also the spring was around 2mm shorter than the new one. Not sure what the pressure is up to now as I aint started it since , for other reasons.

Your oil pressure shouldnt 'sit' at a given PSI. It should be pretty high from cold (say 70 or higher) and then drop to say 30 at hot idle (rising to 70 again when at revs).