Hitchcocks Forum

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

Are the rings the right way up?

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!

There should be "top" marked on oil control rings. (It is also a fairly common mistake.)

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 .

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.

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

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

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?

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?