Yes, the high compression engines, I believe, have a 'domed' piston, so
smashing into valves could be a problem.
Terrence Banbury
> ----------
> From: Dean Dashwood[SMTP:Dean.Dashwood@enron.com]
> Reply To: Dean Dashwood
> Sent: Thursday, April 06, 2000 9:28 AM
> To: spitfires@autox.team.net
> Subject: RE: Strange gnashing clatters/Timing chain
>
>
>
>
> Fortunately, never had a timing chain break on me.
>
> The problems are caused by the pistons making contact with valves which
> are open
> at point in the engine cycle when they'd normally be closed.
>
> But I believe (and I'm ready to be shot down here if I'm wrong) that the
> valves
> in a stock Spitfire, when open, don't move far enough into the cylinder to
> make
> contact with the piston, even at TDC. Like I said, no experience, and I
> certainly wouldn't suggest that anyone try this to find out, but if anyone
> knows
> one way or the other...... Of course, it could well be different
> depending on
> the engine you have, too.
>
> Dean
> --------------
>
>
>
>
> Date: Thu, 6 Apr 2000 08:34:03 -0400
> From: "Banbury, Terrence" <Terrence.Banbury@dnr.state.oh.us>
> Subject: RE: Strange gnashing clatters/Timing chain
>
> I have had two experiences with broken timing chains, each years apart.
> Not
> on a Spitfire, but on GM V8s. I am going to assume the Spit engine would
> behave similar, until someone here tells me otherwise (and I hope they
> do).
> What happened to me was this...
> Driving along, engine is running smoothly. Then it just quits. Just like
> I
> shut it off. It behaves like a complete electrical failure. So
> naturally,
> as I coast along, I try to restart it. Mistake. As I understand it, by
> running the starter motor with a broken timing chain, the valves are out
> of
> sync, so you end up bending the valves all to hell, causing big repair
> bill.
> This was the end of my 1972 Cadillac Coupe De Ville, 472 cu.in. I had to
> choose between restoring the Spit or the Caddy.
> So would the Spit behave the same way?
>
> Terrence Banbury
> Mk III
>
>
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