This Forum is now CLOSED use the link to get more details viewtopic.php?f=3&t=13924#p102587
User avatar
By Tomshayes1
#96501
Hi Guys

My 53 Meteor recently rebuilt (Apprx 500 miles since) has started burning oil..... Blue smoke etc
I've stripped it down and the left hand cylinder is the worst of the two. Piston crown badly coked up with oily black deposit.
Engine is on +0.30 bore.
Top Compression ring gap = .037" Second is .040" and oil ring = .046" .. The max wear limit is .625" ( 1/16") so plenty of wear yet to go. (Left cylinder measured as its the worst of the two).

When I rebuilt the bores were still showing the honing marks so all good and measured up nice and parallel etc.
The pistons both looked fine (6.5:1) so were re used I fitted new European rings from Messrs. H and gapped them to .011"- .015"

New valves and valve guides with valve stem seals were also fitted...

I'm currently a bit miffed....... The ring wear seems allot for basically 3 or 4 rides out!

I've ordered a pair of new "Higher Compression pistons from our hosts (8.5:1) and gaskets etc.

Anything else worth checking before I proceed further?

REgards

Tom
User avatar
By Tomshayes1
#96503
Image
Attachments
IMG-20210425-WA0009.jpeg
IMG-20210425-WA0009.jpeg (2.88 MiB) Viewed 1318 times
IMG-20210425-WA0005.jpeg
IMG-20210425-WA0005.jpeg (2.82 MiB) Viewed 1318 times
IMG-20210424-WA0003.jpeg
Okey Cokey
IMG-20210424-WA0003.jpeg (2.57 MiB) Viewed 1318 times
User avatar
By Tomshayes1
#96505
Hi Papasmurf

I cant see anything to indicate "Top" on the rings i.e a T or any step etc in the rings to indicate which way up!
User avatar
By Wheaters
#96507
After only 500 miles it won't be fully bedded in anyway.
However, seeing that it's already apart, it makes no sense not to pull off the cylinders and check how it all looks.

I'd probably fit new rings after gently de-glazing the bores, making sure they really are the right way up (I'm not saying the ones already in there aren't).

I bought my 350 with 3,100 miles on the clock (and four previous owners...). It had a soft exhaust valve seat which kept causing compression loss so I soon had that replaced. The insides of the cylinder head was more oily than yours look, btw. I left the cylinder in place and after rebuilding the head (and going on to fix a badly made carburettor, another saga, with fuel starvation) I finally got it running well. But then it smoked and used oil.

Now it's done close to 17,000 miles and it gets ridden hard. The oil consumption has reduced and it no longer smokes so it's just about run in :lol: .

However, I recently had the head off again for what I consider a bit of a freak issue (a small piece of carbon got trapped under the exhaust valve head at idle, so again it lost compression). Again, I left the cylinder in place, although if it hadn't resisted my efforts so strongly I wouldn't have done). I noticed there are still some fairly deep factory honing marks in the cylinder so I guess it will always burn a little bit of oil - not a problem.
By vince
#96508
Hi, check the scavenge system, my connie suddenly started laying down a smoke screen which would do credit to a destroyer. A glob of gasket goo had blocked the return pipe, once removed the smoking stopped. Vince
User avatar
By Tomshayes1
#96510
Hi Vince

I'll check the scavenge pipe..

I'm going to have the bores honed and fit a new set of rings but there's no trace of oil up the bores. But the hone should help the new rings bed in.

The valves, guides ec are all new

Tom
By Bullet Whisperer
#96511
Those piston ring gaps have grown to monstrous dimensions! I would say they have worn in and worn out in no time at all - those gaps are your problem, are the rings made of decent stuff, or has something gone in and worn them out?
By papasmurf
#96513
Bullet Whisperer wrote:
Mon Apr 26, 2021 9:01 pm
Those piston ring gaps have grown to monstrous dimensions! I would say they have worn in and worn out in no time at all - those gaps are your problem, are the rings made of decent stuff, or has something gone in and worn them out?
Were the correct rings fitted in the first place?

Shop for accessories at Hitchcocks Motorcycles