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County Pistons

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KVH

KVH

Obi Wan
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Question Number 297:

The manual speaks of installing the pistons to face the correct way. My new County pistons do not appear to have a correct way. Do they?

I see a stamp on top, and one of the four oil holes has a brass plug, but I see no instructions.

Any advice. Thanks again: in advance.
 
On my TR230 motor the pistons had little triangles stamped into them, my machine shop guy said they were arrows pointing towards the front.

That being said pistin should be symmetrical, however, your connecting rods can go in right or wrong on your motor. When I rebuilt my 4a motor years ago, I put them in backwards, didn't figure it out until I tried to turn the motor with the head on (didn't want to break the figure of 8 seals, had to take ut back apart and turn them around.

Maybe the reference to the pistons is actually to the piston and con rod assembly? which does have to go in the right way.
 
To avoid the old unpleasant noise called "piston slap"..(Ever heard an old 216 Chebby fire up cold?) The automotive industry went to "offset" pistons. The piston pin will be slightly off the centerline of the piston so that the thrust side contact is minimized slightly.

Usually you're only talking several thousandth of an inch...

I would contact your sellers and ask them to contact the manufacturer for id installation...

Now more modern pistons are made of material that is less prone to noise transferrence(hypereutic anyone?), but there is no guarantee that the pistons you purchased are made with no need for offset pistons..
 
These pictures show the way for the triangles or arrows, but I don't have any of the rods fitted to the crankshaft.
 

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Yes sorry, tr250, on that motor the arrows point towards the front, I got the impression from my machine shop guy that was fairly standard, but I would get better information than that before making a final decision.
 
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