Roger, I'd definitely deglaze the cyl. walls with a good hone. If you
haven't done it before, take a look at some of the U-Tube videois on honing
the cyl. A moderate speed with a smooth, but not too slow, vertical motion
shlould produce a nice crosshatch pattern. Be careful , because there are
some poor honing methods on U-Tube, along with the good ones.
Then, for break-in, my preference is to drive the first 20 or so miles
conservatively, varying rpm, but avoiding lugging, or full throttle. Then I
gradualloy work up to occasional higher rpm and harder throttle. Then I
start working in some harder runs,in the ~2000 to 4000 or so range. A hill
is often useful for these runs, because you can apply the load without
exceeding speed limits quickly. Let it cool by easy cruising between runs.
The idea is to gradually apply increasing cylinder pressure to force the
rings against the cyl walls so they don't have a chance to glaze. Hard
throttle in this rpm range should help.
I do one session of perhaps 10 runs, and then revert to what might be
considered a normal moderate break-in for the next several hundred miles.
But, I believe that high cyl pressures initially are necessary to avoid
glazing the cyls.
Please note: the above method is MY procedure for break-in of my TR6 engine.
I have not tried it on a Spitfire engine, and it's up to you to try it or
not. Another consideration is that perhaps the rpm range should be somewhat
higher in a Spitfire than for a TR6.I have no experience with Spitfires.
Good luck, Roger.
Tom
----- Original Message -----
From: "Roger Elliott" <elliottr@rmi.net>
To: <triumphs@autox.team.net>
Sent: Sunday, June 21, 2015 3:46 PM
Subject: [TR] Rings Not seating
> Hi,
>
> What is the most likely cause of rings not seating?
>
> I rebuilt my Spitfire engine about 4,000 miles ago and still have
> excessive oil consumption. I don't seem to be leaking oil, so my
> assumption is that it is getting past the rings.
>
> I did check the gap on all of the rings during installation and they all
> were within tolerance - generally towards the tighter end.
>
> I am planning on taking off the head and putting new rings on.
>
> What steps should I take to try to make sure the new rings seat properly?
> I am thinking I should run a hone down cylinders just to roughen up the
> walls a bit.
>
>
> Thanks,
> Roger Elliott
>
>
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