Hi Mike
The test you describe will not check your bores, rather the wear on the
piston and the bore. To check your bores this way would require a new
piston. Is there much of a ridge at the top of the cylinder, check this with
a finger nail, if you can catch it with your nail then a rebore would be
wise, if you can only feel it but it doesn't catch then I would not rebore
yet. Of course the only finite check is with a micrometer and bore gauges.
Don't forget to check the pistons for wear, the ring grooves are probably
the most susceptible to wear and when worn will act as an oil pump to
transfer your sump oil to the combustion side of the piston.
If the pistons are worn standard size and the bores are ok, I would suggest
fitting new pistons after honing the bores, std size new old stock pistons
can be had for a fraction of the cost of plus sizes. If you are honing
without a rebore try to get the balls on springs type hone rather than the
flat pads type as the flat pads type tend to bridge any small imperfections
where the balls type will not thus giving a better surface for bedding in
new pistons and rings.
Graham.
----- Original Message -----
From: "Mike Himelfarb" <mhimelfarb@shoppersdrugmart.ca>
To: <triumphs@autox.team.net>
Sent: Tuesday, February 24, 2004 4:29 PM
Subject: To Rebore or Not To Rebore... That is the question!
> Advice needed gang.
>
> I just finished completely disassembling the motor on my 72 TR6 as part
> of a restoration.
Snip
Clearance should not exceed .010 in. I
> did this test and found a .013 feeler gauge can be inserted about 3/4"
> of the way down between the piston and cylinder bore.
>
> Do I need to rebore? I'm already figuring to hone the bores because
> I'll be needing rings but am worried about boring as I'll need new
> pistons and the $$'s will increase significantly. Advice?
>
> Mike Himelfarb
> Director, Production Services Quality
> Information Technology Department
> Shoppers Drug Mart
> (416) 490-2754
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