Morris Minor Owners Club

(re. viewtopic.php?f=4&t=73539 )

I think the reason my 3 & 4 cylinders are oiling up their plugs is oil getting past the rings (fairly significant oil seemingly getting burnt; and me having to replenish in the region of a half a pint every 200mls or so?).

For now I'd rather not have to go down the route of rebore etc., so I'm wondering what I could expect from fitting a set of "CORDS" piston rings?
I've emailed them if they can provide a set for a Morris Minor 1098, and this is their reply:

"Could you provide me with the bore size you require, qty of rings on the piston their widths and how many cylinders for the engine.
"

I presume my engine is still on its std bore size (as the piston tops are factory marked with "U26" & "U27").
What would be the "widths" of the rings they are referring to - height in the grooves; not depth into the grooves?

And also of course I'm hoping I can hear from anyone who has had the pleasure of trying these rings as an alternative, probably temporary, option?

Thanks guys.

Why not give them both measurements, the depth of piston groove and the height of piston groove, then you have covered It.

A good indicator as to whether the engine has been re-bored or not is having the engine number in its original position. The engine number has to be removed to enable the boring bar to be fitted. Is the engine number still in place?

Bores tend to wear halfway down more than at the top. Before fitting the new rings, place one of the old rings in a bore (on top of a piston to ensure it's level, then remove the piston) and using feeler gauges measure the ring gap, record the result then do the same halfway down the bore then at the bottom of the bore.
This will tell you whether the bore is parallel or not. You should realise that you are measuring the difference in circumference not diameter.

I would not be ordering rings until the engine is dismantled and checked properly. Bores could be scored, they could be oval or the scraper rings may be stuck or damaged. The piston ring grooves may be worn to service limits and beyond. Even rings installed upside down can cause excessive oil usage.

Measuring ring gap at the bottom of the bore will indicate ring wear. Further up, compared to the bottom reading, will indicate bore wear.

Oil may also be going down the valve guides (worn guides, dead or missing stem seals).

Re-ringing a worn engine is rarely the answer. Presuming can be an expensive pastime.

If you want to go to the trouble of re-ringing you might as well do everything else, because if one area of the engine is worn, the rest will be too. Do you really want to have to take it out and do it all again?

...Thanks for all the advice guys...

It looks like it might be better/ least complicated, to look for another engine... I'll keep my eyes out on ebay etc... In the meantime at least I can keep running...

Be careful, second hand engines are a gamble. You may be back to square one. Although you’re not keen on doing up your original engine, you would at least end up with a known quantity.

On a positive note, I stripped and rebuilt the original engine of my 1969 Traveller with new bearings and Cord piston rings some time in the mid in the 1990. It is still running well and I have had no problems.