Lister ha2 piston numbers

[Jrtm]

I've started to strip and clean the ha2 now I know it ran so I can clean it up and then once national is fully running will rebuild it.

 

I've removed and cleaned all the top end im in the middle of cleaning piston, I do have a set of rings about (no idea why) but the number on the pistons don't match to anything. There genuine lister pistons and liners and are in very good condition so will prob hone and reuse,

 

The numbers off the piston are part number 531-18250/7 (the 8 could be a 9 as has a bit of dirt on it but it looks like an 8 when I look at the patern number has a 9 in)

 

Any idea what this relates to e.g. stock or over sized?

[RLWP]

It's the number of the piston, not the piston and ring assembly

 

It doesn't have an oversize mark on it so it is probably standard

 

The correct way to find out is to measure the bore!

 

Do check that the ring groove on the top ring of the piston is OK. 

 

Richard

[Jrtm]

19 minutes ago, RLWP said:

It's the number of the piston, not the piston and ring assembly

 

It doesn't have an oversize mark on it so it is probably standard

 

The correct way to find out is to measure the bore!

 

Do check that the ring groove on the top ring of the piston is OK. 

 

Richard

Hope pic helps, yer I thought stock but wasn't 100% ive inspected the piston (be it still on the engine) and there is only a very slight wear on the side (as an ex engine builder for alfa) the wear dosnt concern and a quick wipe with emery cloth and the coke is coming strait off, all rings are free and coke free, only thing missing was the bottom oil ring but has a grove for it.

[RLWP]

You need to put the top ring into a clean ring groove, then put a feeler gauge between the side of the ring and the piston. As the piston moves up and down, the ring wears the side of the groove.

 

Richard

[Jrtm]

1 hour ago, RLWP said:

You need to put the top ring into a clean ring groove, then put a feeler gauge between the side of the ring and the piston. As the piston moves up and down, the ring wears the side of the groove.

 

Richard

Got a piston grove cleaning tool already setup on lathe for doing this, just need to get the piston out, its all setup from when I did the national engine pistons, ive got a new set of genuine lister ha rings on order and as soon as they arrive I'll strip and test the piston ring gaps, but rest of piston is all OK and as is genuine ill reuse if they can be. If not if there is room ill have the ring groves recut and diffrent rings put in, if not it will get new 10 or 20 thou oversized pistons and have the liners bored to them to match