strange oil pressure symptom

[john.nash]

I know this doesn't matter as any pressure is good pressure in my single.

I have a pressure gauge in the panel; run from a take off on the inner timing cover. Non adjustable.
It's always read around 50psi on a startup and then drops as things warm up.

After I emptied the oil out t'other day, cleaned out the oil tank (dried it all) and refilled with the same monograde oil it started to hit the stop at 100psi.
I tried a different gauge; same result and to measure directly off the timing cover; same result.

Just seems odd.
I have plenty of return and everything.

[nevhunter]

I'd be investigating that. The singles don't need to register oil pressure and you are only getting an indication that the pump is working. Any high pressure is just loading the pump for no purpose and will only reduce the output as it gets hotter. The back presure is only caused either by the adjustable (early) or fixed spring in a ball valve, The later one is in the feed tube to the mainshaft ( big end). I would be checking for an obstruction of some kind.( Piece of oil line rubber etc). Nev

[Keith.owen]

Hi,
From my recollection oil pressue (1950 single) would drop to 10 -15psi when everything was warmed up.

The oil pressure guage is run off of the rocker feed which is in turn derived from the supply side on these machines (later machines took the rocker feed from the return feed).

During some years it was posible to adjust the pressure but it was always stated that this should not exceed 15psi as this would achieve nothing save overload the pump. I agree with Nev. I think you have a blockage somewhere.

Keith

[admin]

Everything off, cleaned and blown through with air (where appropiate).
Oil pressure ball/spring/plug looked fine. Actually couldn't find anything to cause it BUT my pressure is back down to where it used to be.

cheers

[Keith.owen]

UHH!!!

Oh well. The good thing is that you noticed. Seems like the worry guage was some use after all (despite thte fact that it is not considered to be needed) and nothing nasty happened in the long run.

Keith