Yes, this can happen with ANY camshaft. Generally the surface of a
reground-cam is smooth but pretty soft and about the only protection they
get is to be parkerized ( a coating). The main problem for immediate wear
is revving the engine, or blipping the throttle when the part is new. It is
hard not to listen to the sound when you've just finished a modification but
unless you give the engine a run in time period of at least a few minutes at
low revs, just over idle you've got a more than fair chance of screwing up
the camshaft. The slow running ( without blipping) allows the camshaft and
other parts to surface harden. I learned this lesson a long time ago but it
still applies. On occasion it will happen even after this precaution but
not often. The other culpert is a camshaft lift curve that is too big
(radical) for the lifter diameter. This is a thing that can happen with
the little lifters of the Spitfire engine. The lobe catches the edge of the
lifter and peels it like an apple.
----- Original Message -----
From: "Russell" <rjmunns@btinternet.com>
To: "Friend Of Triumph" <FOT@autox.team.net>
Sent: Saturday, January 26, 2002 9:53 AM
Subject: Camshaft failure? :(
> Damn Damn and Double Damn
>
> I have just got back from running my new fully modified spit 1300 engine
> for the first time (after extensive rebuild)only to be frustrated by what
I
> think is a camshaft failure. I booked onto a track day to run the engine
in
> and all was going well (apart from a couple of small oil leaks) until the
> engine started making a lot of noise. It was not a bearing problem but
> something was definitely amiss.
>
> Into the pits and everything sounded ok and all the fluid levels and
> pressures were fine. So back out and no difference, still very noisy, so
> slowly back to the pits. The noise seamed to be induction rather than
> engine noise so we decided to check the valve clearances, all of which
were
> like barn doors (huge). I assumed the pushrods and followers etc had
> probably just bedded in so started readjusting the clearances, only to
find
> that number 5 exhaust was only opening a fraction compared with the rest
of
> the valves.
>
> What has gone wrong?
>
> My theory is that when the cam was re-profiled the cam lobes were not
> hardened properly and they have all worn away quite rapidly as the car had
> only covered 20 miles before the noise started to appear. If this is the
> case which I suspect it is will it have done any damage to the rest of the
> engine. I already expect swarf to have collected in the sump and filter
but
> I suspect I will need a full stripdown to clear the engine of any metal
> particles.
>
> Very annoying but I would appreciate some views on this! Is it common on
> full race camshafts or am I just damn unlucky
>
> Russ (annoyed) :(
>
> -----Original Message-----
> From: Joe Curry [SMTP:spitlist@gte.net]
> Sent: 26 January 2002 16:03
> To: David & Krystal Wingett
> Cc: Friend Of Triumph
> Subject: Re: Hurry
>
> When I was looking into doing a Supercharger on a Spit 1300 I found that
> there were several alternative companies that still make rods (and
pistons)
> for these older engines a lot cheaper than Carillo. Unfortunately, when I
> decided to transplant the Honda S2000 engine, I deleted all the files I
had
> been saving. :(
>
> Joe (C)
>
> David & Krystal Wingett wrote:
> >
> > I think I saw an imitation sold in England (maybe Cambridge).
> Has
> > any one ells found an alternate source?
> > DW
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