In reply to :
From: searle@indigo.ucdavis.edu (Philip A. Searle)
Subject: TR4 Problems
A couple of times now the usually trusty TR4 has died on me.
I drive a TR4a and have had numerous engine stoppages due to bits falling off.
I would suggest pulling the choke out immediately the car starts to misfire, if
it recovers for a few seconds then this suggests fuel starvation, if it doesnt
then its probably electrical. I have heard from someone once of exactly the same
style of failure which occurs as soon as the engine warms up and this was found
to be a dodgy coil, so would suggest replacing this first.
Secondly, a question:
Does anybody have a TR2-6 fitted with the "rocker oil feed kit" supplied by the
UK TR specialists to reduce wear of the rocker shaft? I have had one fitted
to my car now for about 50,000 miles and have certainly found that it eliminates
wear at the top of the engine. Unfortunately I have also found that my oil
consumption can be as high as 150 mile per pint on the motorway (75 mph). This
suggests my engine is totally knackered, which I do not believe to be true.
I also find that my crankcase emission valve is full of oil, and I suffer from
pre-ignition on number 4 cylinder (according to the spark plug). So I have come
to the conclusion that this rocker feed kit is the problem. I suggest it
supplies so much oil to the top end of the engine that a large proportion of
this oil is picked up by the crankcase emission system and delivered directly
into the manifold of No 3+4. A friend who works in the field of engine design
has told me that oil will cause pre-ignition due to its low flash point, and
this certainly fits with my observations. I have now removed the modification
and will observe the oil consumption as a measure of its effect. Hopefully
this will reduce the Vortices of blue smoke which obscure rear vision when
you have the throttle wide open above 4500rpm.
Does anybody have experience of this modification or its effects?
Dave Lacey
Ciba Geigy SA
Switzerland.
blaced@chma.ciba.com
(1967 TR4a O/D, or at least the oxide form of this car)
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