Timing cover drain

George,

I presume you have been following the saga of my freinds oil loss problems from the timing side of his ES2, and I can now report that the leakage is now cured although other problems persist. How did we fix it? After much dismantling and reassembling of the timing side involving checking the pressure relief valve, oil pump and its feed, camshaft bush and the oil return pipes we eventually fitted a different camshaft with an oil return scroll in the spindle and made up a new and accurately sized bush without any oil groove in the bore. We also fitted a larger bore outlet for the crankcase breather, minus the ball valve, and a larger bore breather pipe, 3/8", with a plastic ball valve ot the outer end. As both these mods were done at the same time I`m not sure which one cured the oil problem however Paul Knapp suggested the larger breather and he said it cured all his oil leakage issues so mabye this is the place to start. An unforunate side effect has been that the bike now has much lower compression and poorer performance than previously, in spite of trying three different timings of the inlet cam so we assume this cam is the wrong type.

Good Luck! Tony

Mine leaves a 50 pence sized blob, as did my previous 5 ES2's, It's such an old design, I live with it, oil is cheap.

Hi George, to answer your question,.... no, I don't personallythink the relief valve has anything to do with the excess oil in the magneto chain box. I think that small ball valve only is there to provide the crank oil jet with the initial flow of oil upon starting and at a slow hot idle, by sealing off anyescape route in the oil flow circuit. That small conical spring wouldn't hold much pressure at all. The roller big end needs no oilpressure, only flow to keep it happy. I can't pin point one remedy that cured my excess dripping, (read flooding),but you could try driving the inlet cam bush inwards to reduce the cam end float. You would only need a thou or two clearance between bush and cam shaft shoulder.

Paul

Mike Pemberton told me that it's important to check the ball valve because if it sticks open it will flood the mag drive and starve the big end. So I did and bought a new one from Russel motors.

It's an easy and cheap thing to fix first, if that doesn't cure it you can move onto the more complicated stuff!

Correct me if I am wrong but, are we talking of two things here? The pressure relief valve or the spring loaded jet on the crank end feed. ???????????????

You have to take off the mag chain and sprockets so you can remove the timing cover, the pressure valve is a slotted screw in the cover that is peined over to stop it unscrewing, I broke mine getting it off! but got a new one from Russel motors. The other thing to check is the fibre washer on the oil pump feed, you could be leaking oil there. The washer is the same part number as the AMC gearbox level screw washer I think. I got one from RGM as I didn't have one fat enough. Some people use an o ring but as it isn't retained I think there's there's a risk it will slide out.

Previously boo_cock wrote:

Correct me if I am wrong but, are we talking of two things here? The pressure relief valve or the spring loaded jet on the crank end feed. ???????????????

I'm talking about the pressure relief valve!