Wet sumping holy grail

4 days says your pump needs a refurb even if you fit the non return valve in the timing cover.

Hi Alec. I fited aMKIII timing cover to my MKIIA Commandoa few years ago. It works fine, just remember to get the MK3 pump to cover seal as well.I was advised that it isn't always a perfect fix as the one way valve spring is very light and can stick. The suggestion was to give the timing cover a light tap with a rubber mallet around the valve area if the bikes likely to be standing for a while. I continue to do this. The level may drop a little sometimes still, but not by a lot.

As a point of interest, if I recall correctly the bleed off route from the pressure relief valve was completely different. I think theoriginal cover dumped any oil realised by the valve down a drilling straight to the sump filter, the later cover dumped it into the timing cover? It was quite clear that the draincircuits would work fine on my engine. I remember thinking that fitting my original cover to crank cases meant for the arrangement on the MKIII timing cover would probably result in the oil release passageway being blocked.

Cheers, Jeff

Pre Mk3 timing cover works fine on Mk3 crankcases, I have this arrangement & it's done a few thousand miles now, so I guess Mk3 timing cover will be fine on pre Mk3 crankcases. However, if your engine is wet sumping that quickly, you really should investigate the reason rather than trying to mask the symptoms.

Regards, Tim

hi alec

i dont know about the drain valve mod but i dont use oil that's less than 20-50 but i am sure mono 50 grade is best as most multi grade oils are made for the motor car,A good tip i use on my old 750 motor is i move the engine by hand with the kickstart on to compression when itsput backin the garage

all the best Laurie.

Since I changed from Silkolene Chatsworth 40 back to 20/50 after 20 odd years, regards my 76 Commando; (Leaving the engine on compression) I can now leave it for two weeks and with a good battery (Boyer) it will start first kick. This is not a fluke because I have done it several times since the change back to 20/50 last Spring.

Incidentally, starting first kick with a warm engine and obviously no choke requires almost full throttle. Explain that?

Thanks to Charles B on here fore recommending the change of oil, good advice with regard to Commando's. Just thinking, if kicking a Commando over was difficult with SAE 40 you must need the leg of The Giant Haystacks to even move the Commando kick starter with a cold engine on SAE 50. I keep the straight oils for singles.

Commando not wet sumped since the change to 20/50.