Lister Engine Forum

Lister Engines => Original Lister Cs Engines => Topic started by: mikenash on March 28, 2020, 03:53:21 AM

Title: Big funny piston rings
Post by: mikenash on March 28, 2020, 03:53:21 AM
Hi guys

Our local machinist just failed Common Sense 101 (or at least his worker did)

I bought a 5slash6/1 recently with a long history of hard work on the farm.  Bottom end started out as a 3/1 maybe in the late '30s . . .

When I tore it down it turned out to have a +40 thou alloy piston (kinda an 8/1 now i guess) and the top ring groove was pretty worn.  I managed to buy some ring groove spacers in a suitable size as the 4&1/2 inch piston size was common in Bedford trucks & some other a half-century ago

So I calculated the clearance etc for the ring+spacer, WROTE IT ON THE PISTON WITH A PICTURE and gave it to the machinist we use at work.  He as been bloody good up until now

For whatever reason, he left it to a worker to do who mistook the vertical dimension for a lateral dimension and machined what could only be called A Very Big Groove into the piston

By the time I got it back it was one of those "what's done is done" situations

His solution was to accept that the piston now has a very big ring groove and to get a Very Big Ring machined by a bloke who makes one-off piston rings . . .

See pics?

What do you guys reckon the implications are?  I'd be interested to hear from some experienced folks

Cheers
Title: Re: Big funny piston rings
Post by: broncodriver99 on March 28, 2020, 06:59:44 AM
That's a very big ring. Would suit a locomotive just fine. Does your 3-5-6/1 happen to be called the Dursley Express?

On a positive note there is likely little chance you will break that ring due to a cylinder ridge.
Title: Re: Big funny piston rings
Post by: listard-jp2 on March 28, 2020, 03:50:41 PM

What do you guys reckon the implications are?  I'd be interested to hear from some experienced folks


Depends alot on what sort of wear ridge you already have in the cylinder bore, and where the top edge of the top ring is now in relation to the wear ridge (if you have any bore wear).

A company called Cords piston rings (in the UK) used to make piston rings for use in worn bores, and the top ring incorporated a 'ridge dodger'

Another alternative for you to consider would be to see my ebay listing of oversize Lister CS pistons (UK manufactured)  https://www.ebay.co.uk/itm/LISTER-CS-NOS-GENUINE-NOS-HEPOLITE-COVENTRY-PISTON-BACO-OVERSIZE-VA-6-1-8-1-/254185213781
Title: Re: Big funny piston rings
Post by: mikenash on March 28, 2020, 10:36:49 PM
Yes.  Good call.  No ridge - I have given it a hone and it's worn/loose but OK for an old CS

In the Current Emergency I'm not sure how internet sales are working?  However the company I work for is "essential" in the current lockdown so we have courier deliveries etc

If you wanted to look at a $$ figure inclusive of delivery to NZ for a cast +40 thou piston and rings, I'd be happy to consider it?

PM me if you like?  Appreciated.  Thanks
Title: Re: Big funny piston rings
Post by: listard-jp2 on March 29, 2020, 09:16:45 AM
/\ If your interested, just do a Buy It Now on the ebay listing, and it will be shipped to you using the ebay global seller program.

No problem with ebay sales in the UK at present, sales are depressed, but are still happening.
Title: Re: Big funny piston rings
Post by: dieselspanner on March 29, 2020, 01:40:56 PM
Hi Mike

eBay Sale seem to be running OK as far as deliveries to the Pyrenees go. I'd guess a lot of vendors are small outfits that work from home. With the current situation I'm starting to catch up on all the 'projects' and bits are still arriving from the UK.........

As for the ally piston, I may have the answer, My 3/5/6/8 - 1 bitza started out as a 3-1 hopper cooled in 1934, according to the info plate. It arrived with the 5/6 - 1 top end and that's how I put it back together

When I ran it up it was tramping up and down the workshop like guardsman on rum. I stripped it down again went through the 38ac balancing routine and a couple of others for good measure, It looked like it needed masses of weight on the flywheels.

I sent off to Dev Precision, Rajkot, and within the week an ally 8 - 1 piston arrived, complete with rings, I fitted it and it ran up with no vibration whatsoever.

It starts to throw it's self around just under 700 rpm, where I have it at 630 it's as sweet as, under any load

I did ask on here, at the time, if there is any difference between the flywheels of the 3 -1 and the larger, later, CS but never got an answer. There's a significant weight difference between the ally and the iron piston so I'd bet a slab of beer there's something in the theory!

The Cs has been laid up for a couple of years, but if the C19 lockdown gets extended, in France, it'll be getting dug out for the fitting of the Land Rover starter motor I scrounged up a couple of years back.

I've caught up on the honeydew list and SWMBO would rather I was 100m away in my 'man barn', if I 'forget' my phone I'm guaranteed at least 3 hours of peace!

Stay safe, one and all,

Cheers Stef
Title: Re: Big funny piston rings
Post by: cujet on March 29, 2020, 08:04:43 PM
I've seen piston rings doubled up, much like the Total Seal rings. That generally does not work all that well, but it can work.

Title: Re: Big funny piston rings
Post by: mikenash on March 30, 2020, 07:36:31 AM
/\ If your interested, just do a Buy It Now on the ebay listing, and it will be shipped to you using the ebay global seller program.

No problem with ebay sales in the UK at present, sales are depressed, but are still happening.

OK.  Cool.  I have ordered one of the 6/1 +40 thou pistons and that will give me a good spare at a reasonable price

My delivery address says "essential irrigation spares"  That's because, with the Covid virus, our country is in lockdown apart from essential industries - of which mine is one.  If the labelling says "essential" chances are couriers will deliver it.  If not . . . hmmmm . . .

I guess we'll see

Thanks for the various advice around rings etc here and there as well
Title: Re: Big funny piston rings
Post by: listard-jp2 on March 31, 2020, 09:31:00 PM
/\ Your piston was posted today PM, you will be advised by ebay when it enters the global shipping program.

Title: Re: Big funny piston rings
Post by: glort on March 31, 2020, 11:34:23 PM

OK.  Cool.  I have ordered one of the 6/1 +40 thou pistons and that will give me a good spare at a reasonable price

My delivery address says "essential irrigation spares"  That's because, with the Covid virus, our country is in lockdown apart from essential industries - of which mine is one.  If the labelling says "essential" chances are couriers will deliver it.  If not . . . hmmmm . . .

Well done Mike on not letting restrictions that are trying to stop the spread of a deadly disease prevent you from getting something you didn't even need in the first place!
The most important thing in this unprecedented emergency is that our individual and selfish whims and needs are all met and we don't let anything inconvenience us in any way. If it does then clearly we should flout the system whenever it does so all our individual whims and desires are met. 

Labelling that spare part as an essential supply was a stroke of genius. Nothing like using ones position to get what one wants.
Perhaps the couriers resources are stretched delivering real essential supplies instead of spares that are going to sit on a shelf for however long, but clearly you haven't let that stop you or have any concern for potentially exposing others to needless risk. Your gubbermint trying to save your and other peoples Lives thank you for your Trech  resourcefulness.

Well done Champion!  If I ever held any questions of your personal credibility, I certainly have none now. 
I finally understand what you mean in your often used phrase " At the bottom of the world".
Title: Re: Big funny piston rings
Post by: mikenash on April 01, 2020, 08:29:54 AM
lol.  Thanks  :)