ES2 burning oil and then nipping up!

What speed were you riding at? Sounds like you need to take it very steady until it's run in? My mates Velo was nipping up on the small end bush being a bit tight and not the piston.

Previously andy_marks wrote:

When I first started my newly re-assembled ES2 up a few days ago there where clouds of white smoke and the plug fouled up and stopped within a few minutes. After a conversation with Mike Pemberton I blocked off the feed to the back of the barrel and unscrewed the pressure release valve another half turn. I have fitted a new spring as when I told him where I'd got it from he said they are very strong so undo it a little more. When I took the exhaust off to get at the timing chest for the pressure release there was a puddle of oil in the exhaust port!

I started it up again and the smoke was still noticable but nowhere near as bad so I thought I would go for a test ride and see if it was just burning off what was already there, however it was now about midnight so it would have to wait for another day.

I have just got back from my first ride down the road on it and I managed about 2.5miles before the engine nipped up, I sat on the side of the road for 5 minutes to let it cool down and it started first kick and rode home via a slightly shorter route. It's still smoking quite a bit and there is oil being sprayed out the exhaust port (need to have another go at seeling that, but thats not a priority right now). So there appears to be a lot of oil getting up to the top of the engine, the plug is pretty black, but it then nips up... Any ideas?

This is with about 6thou clearance on a WD 16H piston.

Thanks in advance

Andy

Hello Andy,

Had a very similar problem after a rebore and piston engine nipped up and was stiil smoking after the rebore.Fitted new set of rings already fitted new valve guides checked clearnces all OK, still smoked, remove head and oil on top of the piston refitted with out oil feed to rockers still smoking. What next was a bit expensive but worked, re sleeved the barrel back to standard and had the return oil ways from the rockers grooved out on to take an O ring and bought a new piston from Andover Norton also did away with the head gasket having and getting a good mating surface between head and barrel.

Hope this helps.

Den Bourne.

Could the inlet valve guide be the source of the over-oiling? It's a common cause of heavy smoking plus oil in the exhaust port.

Hi Andy,

I had some very similar issues with my 1959enginedES2a few years ago. I have a large piston in it giving 530cc. The rebore was made with a 4 thou interference and boy it was tight at first.There was also a lot of black smoke. At first it did stop but later I found it down to Ethanol melting the pet seal and blocking the petrol tap. A new petrol tap, tank clean out and BP Ultimate cured that.

I was also finding oil dripping from the small pipe from the timing chain case. The plus the plug was and remains oiled up, though not so bad now. I'm working on it.

While I use an Amal Mk 1 and a 20 tooth g/box gear, the carb bits were all wrong. I think something like 240 main jet and 3 1/2 slide.Remember the gearing... on one journey on a very warm day I decided to weaken the mixture screw to try and get the plug colourright. On my way home it started to nip up and make an unfamiliar noise, this was after about 1,500 miles on the clock, Thankfully a layby was just up ahead to coast into with clutch lever in. I enriched the mixture slightly, remember the slightly higher gearing with small throttle openings, ten minutes later I was on my way.

BTW, the silencerwas very oily and the oil got dirty very quickly. Last year I put the std ES2carb bits in, ieNo4 slide and 270 main jet and what a difference. Almost 2000 miles on the clock now and just about run in, it has taken this long.

There was no way the engine was coming apart and I'm glad that was the case. Some small changes, regular checking and miles on the clock is my advice.

Andy, all is well now, though the complete cure took near 2K miles. The plug is still a lot darker than I'd like but better than being white!

Smoking and oil from the timing chain relief took over a thousand miles to stop but don't forget that my bore was tigher than yours and my carb at this time was way out.

I use SAE 40 oil and add a bit of 30 at the back end to help with cooler weather. No need for oil changes every few hudred miles any more!

Just theorising.....

I trustyou have the pistonskirtspray barback on Andy? itis acoolerfor the piston which istightening up in the newbore...

Puddlesof oil in theEXport wouldonlycomefromtheguide, notapiston transfer asthatwould have knockedout thespark plug firststroke.And with the description of "oil Spraying out" at theEXthat also suggestsover oiling atthevalvegear.Twodifferentissuesmaybe....

Tryknocking thefeedoff to thetopratherthan thebottom;may giveyou a better clue. Keep us informed; wouldlike to knowwhich theory holdsout. PS: Take the "Inter" anyway