unusual oil loss

motoholic

Forum User
VOC Member
Hi

when I prepared my Rapide yesterday for a run on this weekend I discovered huge oil loss of crankcase oil leaking from behind the gearbox cover/sprocket.

Until now I didn`t mind finding oildrops beneath this area and have allready fixed new rubber rings to the valve lifter but there must be another leak and a puddle in seize of a beer mat 1 minute after stopping is to much ! Dropping get's less later.

I have to look for this .

I didn`t expece crankase oil in this area.

Would be glad to get suggestions from the experts where to look first.

Soon help will prevent that I will have to take a BMW this weekend.

Regards

motoholic
 

Len Matthews

Well Known and Active Forum User
VOC Member
Hi

when I prepared my Rapide yesterday for a run on this weekend I discovered huge oil loss of crankcase oil leaking from behind the gearbox cover/sprocket.

Until now I didn`t mind finding oildrops beneath this area and have allready fixed new rubber rings to the valve lifter but there must be another leak and a puddle in seize of a beer mat 1 minute after stopping is to much ! Dropping get's less later.

I have to look for this .

I didn`t expece crankase oil in this area.

Would be glad to get suggestions from the experts where to look first.

Soon help will prevent that I will have to take a BMW this weekend.

Regards

motoholic

Is it really crankcase oil? Have you checked the gearbox oil level? Another possibility is excess oil from the primary chaincase could have travelled through the left hand kickstart tunnel if the tunnel has not been plugged.
 
Last edited:

chankly bore

Well Known and Active Forum User
Non-VOC Member
Check your Primary Chaincase level and your Crankcase level immediately after a 20 or 30 mile run to establish what is normal in your motor and the check these two volumes after the machine has been sitting a couple of weeks. You should be able to clean around the sump plug and return the measured oil to the tank. This will establish whether the machine is "wet sumping" which is oil flowing past the oil pump and/or sleeve as it fits into the crankcase. If this is the detected problem, then most likely your crankcase is pressurizing the oil and forcing it to escape wherever it can most easily go! There are cures for the symptoms if this is the case, but the only sure and specific nostrum is a new and well- fitted oil pump assembly. The foregoing assumes that it is engine oil that you are finding. Let us all know how you get on! Cheers, F5AB/2A/7945 since 1970
 

motoholic

Forum User
VOC Member
It is indeed dark crankcase oil. Gearbox oil level has been checked and found o.k. and honey coloured. Wet sumping can be the main raeson as the bike has been standing for about 1 mounth and afterwards been driven for 10 mls. As I understood, the oil could reach the sprocket area via the Kickstarter tunnel. Where is this blocked ? Primary side ?

Indeed I discovered heavy oil consumtion in combination with smoking from the exhaust on hot engine. Valve guides I assume . Therefore a great overhaul will be necesarry next winter but I would like to lock the Kickstartertunnel before as first rescue. Draining oil before starting is allthough a good idea.

But : In case of wet sumping : from my exsperience dropping would stop after some mls. as the plunger has emptied the sump than. Isn't it ?
 

motoholic

Forum User
VOC Member
After thinking about your proposuals, I went to the garage and checked again in calm : only a few drops under the bike. Primary cahincase : oil beneath normal leveL !!!! ..would have never reached the level of the kickstartet tunnel. ( Chain needs to be tensioned ) I took a torch and examined the right hannd side : what hose is this ??? ..comming from the UFM/oil tank. Got it : the engine has blown the oil off !! As I'm used to heavy oil consumtion and because my oil is stocked only where I left, I filled up the oil on cold engine !!!!! Beginner - mistake !!! and that after riding brit-bikes since 35 years = awkward !!! Sorry, seems that I'm getting old.

After all the Rapide starts first kick = weekendtrip is rescued.

Thank you for your tipps : maybe usefull next time. Hope that this discussion will warn others to draw wrong conclusions.

Motoholic
 

ogrilp400

Well Known and Active Forum User
Non-VOC Member
Yes Dave. Many a novice Vincent owner (and some just not thinking) have peered into the oil tank after the bike has been standing in the shed for a month or more. Seeing the oil level way down have then filled the tank to the correct level. Riding merrily off into the distance they are soon confronted with a small geiser in front of them and all over the tank, engine and their crotch as the engine returns all the oil that has leaked into the sump back to the tank. Always check the oil after a short ride.

Phelps.
 
Top