Pistons and piston ring end gaps

[welderpaul]

Hello all.

Couple of questions - Firstly; the ring end gap for the top and second compresion rings should be between 0.254-0.381mm and 0.2286-0.3302mm respectively according to the Perkins handbook (Engine model P3/144). The new rings i have just tried in at the bottom of the bore give me an end gap of 0.54mm. They are the existing liners, but when i measure the bore it is still within the limits given by Perkins - very little wear on the bores shown by a minimal ridge i have reamed off the tops.
Out of interest i tried the old ring back in - the end gap was in the order of 2.5mm!!! The engine ran ok, and didnt seem to struggle in any way.
They are ebay-bought Dexta rings. Can i obtain longer (?) rings and file them to give me the correct end gap? Or will the new rings be ok at 0.54mm end gap?

Second question - I know the pistons are stamped 1,2,3 to correspond with the bores, 1 at the front, 2 middle, 3 back of engine. I know the con rods go in with the number stamp go to the camshaft side of the engine, but which way round do the pistons go on the ends of the con rods? Does the number on the top of the piston face the front of the engine?

Last question - The big end con rod cap is also stamped with a number, does this face the number stamped on the con rod? Would seem to make sense but nothing on here or in the book to confirm.

The thing was so mucked up when i took it apart i could even see any of the numbers!

Thanks in advance.

[Mjg1705]

Hi can't help with the gaps - but as with regards to the numbers - from what I have done in the past - numbers on pistons face front of engine - and big end caps and conrods numbers go together - like it would seem -

[Lesfen]

Hi,

I found the same end larger end gap on new rings for our Super Dexta!? (Also checked at the bottom of the bore that was even on the smaller side of the allowances.)
Frustrating as I got the rings from the local NH dealer even though they were nearly 3X as much as aftermarket.
(Thought they had made a mistake and sold me rings for a Dexta but not so.)
And can not find any service documentation calling for a greater end gap from either Ford or Perkins.

From the Ford Motor Company Ltd, Fordson Dexta & Super Dexta workshop manual >>>
Connecting rod caps must be fitted with the stamped numbers together and on the left-hand side of the engine (opposite side to the the camshaft).
Different than most other engines, I think?!

Cheers,
Les

[welderpaul]

Thanks

The Perkins book says 'when fitting pistons and connecting rods to the cylinder block and crankshaft, ensure that the side of the connecting rod which is stamped with the number goes to the camshaft side of the engine.'

This would mean the stamp marks on the con rod and cap are on opposite sides. Seems a strange way of setting up???

[Lesfen]

Hi,
When the Fordson manual states 'the stamped numbers together' I take it to mean both the cap and rod numbers are to be on the same side.
But don't know why they would be different than Perkins (or most others for that matter).
Wonder how they are positioned on the Major engines?
We have a Super Dexta engine apart and the numbers were away from the cam but a previous owner has had the pan off so....?

Best of luck,
Les