[modern] Re: Modern Digest V1 #3046

From: “Stewart Weller” xj40soverign@hotmail.com
Subject: Re: [modern] XJ40 reliability

Loose tappet guides are totally unheard of in the UK!

Don’t say things like that!!!

Not in my experience. Once they went to the catalysts, it was fairly
common.
The XK engine was never intended to run the greater underhood and engine
temps that the catalysts cars achieve.

I had a 1980 4.2 XJ6 SIII that suffered not only from loose valve
guides but loose tappet buckets as well! This engine wasn’t fitted
with a cat.

To paraphrase what I’ve just said, the 4.2 SIII was under-geared. This
meant that at 70mph, the engine was twisting merrily at over 3,000
rpm. (As an example, my XJ12 would be doing about 100mph at these
revs) As a consequence, the engine used to get far too much heat build
up inside it during the course of a long run.

Not only did it used to throw valve guides and tappet buckets, it also
used to throw radiators as well. They always used to go at the joint
between the fin tubes and the side tanks, adjacent to the top hose.

Don’t get me wrong—the SIII is an excellent car, but you need to
either get one with a manual box or convert it yourself so that the
engine is not screaming at stupidly low speeds.

AlastairOn Wed, 26 Sep 2001, Modern Digest wrote:

	----------------------------------------

		There are things known,
		There are things unknown...
		In between are The Doors.