Heavy wet sumping

Information relating to the Matchless G9 or AJS Model 20 500cc twin
magnusk750
Member
Posts: 98
Joined: Mon Aug 08, 2016 9:25 pm
Location: ESTONIA

Re: Heavy wet sumping

Post by magnusk750 »

No problem with your english, I think it's far better than mine. Annars kan vi snakke skandinavisk, jag är svensk, men bosatt i Estland :) Thanks for pointing out about about the non return valve, will check that.
magnusk750
Member
Posts: 98
Joined: Mon Aug 08, 2016 9:25 pm
Location: ESTONIA

Re: Heavy wet sumping

Post by magnusk750 »

More oiling troubles. For the first time I had the engine running for a while. 5-10 minutes. It's the second time I have it running, first time just very briefly. Proper oil return, but under valve covers it's totally dry. Bottom end is 55, cylinder heads probably 52-53-ish. Two screws valve covers, but no oiling grooves in the rockers.

I can see several reasons for dry valves-rockers: 1. wrong or incorrectly fitted head gaskets. 2. Not been running long enough to pump up oil to the heads. 3. Cylinder heads and rest of engine don't fit together. 4. something else?
User avatar
dave16mct
Member
Posts: 3268
Joined: Mon Jan 01, 1990 12:00 am
Location: LANCASHIRE UK

Re: Heavy wet sumping

Post by dave16mct »

More likely to be the metering jets blocked in the heads. They have a very small hole, less than 1mm. I use a very fine guitar string to clear them but I think you'll have to remover the heads to clear them. Early 55 had a different oil metering jet (next to the oil filter in the crankcase) then quickly changed back to the rotating oil distributor 022385. Perhaps check that if you've got the distributor that it's OK. My 55 twin had the distributor and I had no problems.
Dave
Post Reply