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[papasmurf]

jyrkik, as a lot of use have found out, that could still be too much oil.

[Frank]

Was the cylinder honed after the rebore?

[jyrkik]

Hello,

The cylinder was reworked in a local well respected workshop. I cannot really say if it was honed, but I believe so. They even mentioned that they have worked with several Bullets as the Finish importer of Royal Enfields used to reside nearby also (saddly, they're out of business now).

So far I have also changed the oil feed bold (the thing with the rubber crommed) inside the timing cover, stripped the top end once again and changed the order of piston rings (the one with "top" marking is now in the middle as adviced earlier), but notghing seem to help. This Morning the bike smoked again like a locomotive even I had parked the piston to top dead center for the night.

I'm gradually getting enough of Enfield after more than 10 happy years. Prior to this spring there has been little issues. I've even completely overhauled the engine once few years ago and had no issues like this then.

Jyrki

[Frank]

Honing should be obvious as the surface of the cylinder will have been scored or roughned up like you would get rubbing it with emery cloth. Sounds counter productive but it aids the rings bedding in. It might be worth checking compression and the piston/ bore clearance. It could have been overbored. Was the rebore done to match the piston, did the shop have the piston to size up to? Also worth checking the piston ring end gap measurements and that the gaps are staggered and not in line up the piston.

[Tim NZ]

You need to check and confirm WHERE the oil is coming from?


Oil tank? Oil level in tank drops slowly...


Timing chest?


No apparent change in oil level from tank...


,br>
I is very rare for the joint between the crankcase to suddenly allow oil to pass from the tank into crankcase. The usual situation is that the pump disc needs reseating. ..




Inspect BOTH oil pump discs (feed & return) AND seats for any scoring...


Both working surfaces are supposed to be perfectly smooth; no scratches or scoring. Reface and lap accordingly




IF the oil is draining down out of the timing chest, (highly unlikely) is is possible, though a touch tricky, to remove and renew the Oil seal on the end of the crank shaft.




What ever the situation, DONT ride off, or rev the motor with a wet sump situation as high oil pressure in the rocker oil line can occur.

[jyrkik]

Hi,

I'am quite sure the oil is coming from the timing chest and not from the oil tank. If I drain the sump and pour the oil back to the tank, no oil is dripping from the sump even during a night unless I run the bike hot inbetween.

So far I have
- changed the oil feed bolt (the one with neprene seal inside)
- changed the timing chest gasget
- lapped the oil pumps
- checked the order of piston rings

But the bike still smokes like a locomotive if the sump is not dripped empty before the start.

The bike has healthy compression and runs fine if only the sump is drained before startup. If not, it smokes badly. If I leave the sump dripping for a night after a ride, in the morninh there is 3-4dl of oil in the bin. Even if the piston is left to the top dead center.

I cannot imagine anything else anymore than that the crank seal
must be leaking. Have to order a new one and change it. Oh man..

Jyrki

[Tim NZ]

It would be prudent to Double check, and in this instance to drain the timing chest after a ride, add the oil back to the oil tank, and see if you still have wet sumping the following day?


The most common cause of a 'sudden' wet sumping issue is the fit and finish of the Feed Pump disc/plunger, and the Seat in the cover...


If you like, you can leave the crank drain-plug out too, and see how much oil drains knowing that the timing chest has already been emptied? It will confirm matters 100%...

[jyrkik]

Hi,

I may still try that to be 100% sure. However, I already know that the timing chest has been practically empty every time I have opened it. In order to lap the pumps for example.

Jyrki

[jyrkik]

Ok,

Drained the timing chest after a ride (by opening the timing chest for a moment) and poured the drained oil to the oil tank. Opened the sump draining bolt and placed a tin below it for a night. In the morning the tin was still almost empty. Hence the wet sumping definitely is due to oil leaking from the timing chest to the sump somehow. Ordered a timing side crank seal...

Jyrki

[vince]

Hi jyrkik, How many miles have you run it since the rebore? it may just be the rings need bedding in, also check that there are no restrictions in the oil return side or a clogged breather. a teaspoon of oil can lay down a smokescreen worthy of a destroyer. All manner of strange things can happen that at first dont appear related, it maybe a old sparkplug giving a weak spark until it clears itself. I remember a friends triumph smoking badly on one cylinder, the timing was out on that side only. If it runs ok after the initial start then dont start stripping , it may only be a temporary anomoly. Vince. Ps mine did exactly the same then stopped doing it!
Also as a footnote have you fitted the lumpy piston since the rebore?