Size of PRV domed nut?

[DRMM]

Does anyone know off-hand what the size of the pressure relief valve domed nut is? I don't seem to have a socket that fits (1098 engine), so will have to go out and buy one.

I thought I may as well check it (after doing the oil flushing scenario and two fresh oil changes, three new filters... the oil filter light is still staying on and still not much if any improvement to the oil getting up to the rocker box)

[ManyMinors]

1 inch AF fits mine.

[philthehill]

The oil passage to the rockers is very small in diameter and it does not take much to block the passage.

See wksp manual for oil flow sectional drawing for oil flow circuitry.

By all means check the oil pressure relief valve but it does not have much bearing on the oil delivery to the rockers.

I would suggest that you do nothing more as regards oil changes etc until you have fitted the oil pressure gauge and reported back.

[DRMM]

Thanks Phil,

...I'm still on the oil gauge - have the pipe and adapter but somehow didn't manage the gauge yet - so much choice on ebay regards the gauge... missed some chances and others the bidding went too high.

Anyone have opinion if the cheap ones will still work? Some look a bit grotty but if they work I could buy just to test the pressure temporarily.
I'm also paranoid I'll get the wrong connection thread or end...

[DRMM]

... I've just bought an AC Delco gauge, will it be the right thread - 1/8 BSP?

[StillGotMy1stCar]

Yes the thread in the block is 1/8th BSP Tapered.
Regards John.

[philthehill]

The threads in the block are parallel. The fitment which screws into the block has taper threads so as to grip and seal more efficiently.

[DRMM]

... I've just bought an AC Delco gauge, will it be the right thread - 1/8 BSP?

Sorry, my grammar wasn't very good there - I meant is an AC Delco oil gauge 1/8th BSP (if anyone knows off-hand)? I've already got the pipe which was advertised as 1/8th BSP, so I wanted to make sure I didn't make mistake by buying a gauge with different fitment thread.

1 inch AF fits mine.

And thanks for that ManyMinors. Mine looks to be about an inch across too, so I guess that's the one I need.

I think I'll wait and test the oil pressure first now though before potentially changing the PRV influencing factor.

[StillGotMy1stCar]

If the gauge you bought goes up to 75 psi then yes it does look like 1/8 BSP the same as the Smiths gauges. The pipe fitting is sealed to the gauge with a small fibre washer.
Regards John.

[DRMM]

Thanks John, yes mine is that one - 0 - 75psi... so phew.