Re: Unleaded valve clearances

[Ian Soady <ian@domain.elided>]

In message <199904091925_MC2-7142-BC08@domain.elided>, Mike Wattam
<MikeWattam@domain.elided> writes
>Hi Ian
>
>I read your write-up also in another magazine.
>
>Please do not forget the 'memory' effect of having used unleaded in the
>past.  It is believed from experiments caried out on aircraft and marine
>engines, that this 'memory' can last for up to 5,000 miles if the car is
>not driven hard.  I am not surewhether your engine has been built with new
>valves/re-ground seats or what, can you enlighten me please?
Yes I'm aware of this but have never seen it properly quantified - & I
feel better safe than sorry as it's my main long distance vehicle. I'm
afraid I don't know the history of my engine prior to the last 27k miles
as I bought the car from someone who'd had the engine rebuilt *by
someone who rebuilds racing engines* - presumably reasonably competently
as I've had no problems with it so far.... The engine number would
indicate a Mark 1 engine (although a Mark 2 car).

>The valve clearances really need to be checked with each cam on its base
>circle, when this job becomes very time-consuming. 
True but I find a (careful) pair of mole grips on the power steering
pump serves well to turn the engine over. It's nice to have a look in
there anyway. Aren't the cams nice and wide (about twice as wide as a
Jag XK engine).
>
>IMHO - Mike Wattam
>Chairman - Triumph Stag Register
Sorry about the delay in replying - been cruising round the Rockies in a
motor home for the last 3 weeks. Didn't see any Stags - but 1 Spitfire,
1 MGB roadster and saw an ad for another Spitfire for $1200. Seems
cheap.

-- 
Ian Soady