Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Coventry Climax oil pressure valve

Can anyone tell me, or better still provide a picture of where I can locate the oil pressure release valve on my 1122 Coventry Climax Engine?
I think it might be dirty as the oil pressure is fluctuating and not with engine speed etc.
It's recently rebuilt and on 'running-in' oil.

Cheers,

Simon

No idea but the MSCC has a experts who would know.
https://www.morgansportscarclub.com/

Simon

My friend John Merton who is a lurker on this forum had this to say in an overnight email from Oz.

He apologises that he cannot help directly at the moment directly because my bits are in Canberra and I'm in Tuross.

However he suggests that this problem is typical of the oil level in the sump being a bit low.. Perhaps suggest if you add another half a pint or even a bit more and see whether or not there's any difference.

Hope this helps you

The Brooklands Workshop manual says:

The course of oil from the sump is as follows:

Upon being drawn up the suction pipe, the mouth of which is situated about 1/4 inch from the bottom of the sump oil passes through a gravity operated ball valve to a gear type pump. From here it is fed under pressure to a gallery case in the cylinder block and in turn by branch ducts to the main bearings of the crankshaft, which, being drilled, permits oil to be conducted to the connecting rod big-ends.

If this is what you're after it will be the only useful thing I've ever found in the book!

Hi Simon,
There are 2 ball valves. The one is as tmg has mentioned in his post. The second is located where the feed from the block goes via the copper pipes to the head and oil pressure gauge. This ball is held in place by a spring. It is possible either or both the balls are pitted or the spring may be weak.

Has the gauge been bled at the gauge end?

Many thanks. I did an oil change to straight 40 for the winter last night, and now it's also up to full level again. I'll see how it fairs and then look at that ball and spring as helpfully advised above. Yes gauge is bled.
Great to have a few CC experts about, as the printed information is pretty sparse compared with being used to a good Haynes manual for my 1970 car!

Simon

Hi Simon,
One thing to look out for is oil getting on the clutch. The back end of the crankshaft does not have an oil seal but stops oil from going onto the clutch by a reverse thread to throw the oil back to the crank. The oil can flood this screw when going up steep hills, If you have a standard climax sump put the correct volume of oil in the engine and check the dip stick you may have to put a new mark on it.
I once had clutch slip at Harewood hillclimb and finished my run with a Ferrari Tasman on my tail as I entered the paddock.

Gareth,
Interesting. I put 4.25 Litres in with a standard sump to get up to the original full mark on the dipstick.
I'll be back with more questions I'm sure, but off to do the VSCC Bowland rally on Saturday in Lancashire first. Shame speedo drive from meadows gearbox not working, so that's my next job.
I'd be really interested to see a fully prepared series 1 CC-engined beast, and I used to live a stone's through from Harewood, but now am in Aberdeen.

Simon,
My car is in bits being rebuilt. I am looking to get it back on the road early next year. Last time it was used was 1990.
I've sent you a PM.