LM or ML piston rings

[Howard Wright]

Hi All

I’ve started to put together parts for a spare engine.  This will be a minimum cost build so I’m trying to use what I have.  

I have a set of 57.41 pistons which I assume is +60 thou and the slide nicely in the bores of the block I have. They are labelled LM or ML 35 and have three ring grooves which all take solid rings a shade under 3/16” deep and 1/8” thick. Picture below.  

I don’t have a full set of rings so can anyone identify the pistons or recommend a supplier of custom rings?

Cheers

Howard

[Ian McGowan]

Hi Howard, I would start off by having a word with F.W. Thornton 
 https://www.fwthornton.co.uk/ They are based in Wellington (nr Telford).

[Dave Wortley]

Howard,
There"s coxandturner.co.uk recommended on here a while back.
Cheers,
Dave.

[Zetomagneto]

Hi Howard, these are an old design, rings will probably cost you £80 or so. You might decide to use new pistons and could offset the cost by putting these on a popular auction site as ash trays.
Special is looking good! Did someone say DVLA were not dealing with registrations at the moment?
Best Wishes Gene

[Bob Culver]

Original pistons had rings 5/32 vertically and 1/16 radially? Many replacements were thicker which accentuated wear of the top groove. Sometimes remedied by tunring out for two thin, but a sign of high mileage.
If not unduly worn there is no law saying rings have to be replaced. Second rings are seldom much worn. The oil rings are not an odd size. A vague idea of cyl wear can be got from change of gap, taper typically about half the change. Can also file wire or nails and use as an internal gauge.If pistons are not split skirt the clearance is quite generous new.
Even if not seriously worn, the bores may not exactly suit available replacement pistons.

[Howard Wright]

Thanks All

I’ll contact the firms after the weekend and get some quotes. Then see if it is worth going for new pistons.  

Zeto thanks for the kind words, DVLA have notices on their web site stating they aren’t processing paper applications.  I can’t get the club officer here to inspect the car til after lockdown anyway. I’ve also got a dropped axle that needs the eyes done but that will have to wait  .

Shame as I’m itching to try it out!

Cheers

Howard