In <970828233116_1388199734@emout18.mail.aol.com>, JHoltslag@aol.com wrote:
>Going 50 in a TD (sans top) is a pretty “exhilarating”
>experience. I can’t imagine going 65 with 4.3 gears.
Actually, if it's stock, the gears are 5.125. My experience is that a
reasonable highway cruising speed is about 4500 rpm, which gives about
55 mph, depending on the air in your tires. But you still think about
the clutch shattering and flying out into your kneecaps.
>
> But I do have a question. Never having owned a car with solid lifters,
>how do you know if the tappets are making too much noise and need to be
>adjusted (car seems to run fine). Also, I was under the impression that you
>could adjust tappets when the car is idling, but my MG workshop manual seems
>to imply to adjust them with the engine off. Should you adjust the XPAG
>tappets with the engine running or not?
Adjusting tappets during idle was a trick done by my dad on iron like
the old Chevy stove-bolt six (from which, arguably, the B series
engine descended). He said he learned it from his dad, which implies
that it was fairly common practice in the early days of motoring.
It's actually fairly convenient, albeit a bit messy. You don't have
to move the crank around by hand, but it tends to spray some oil.
I don't think it's a good idea with an XPAG engine. The idle is much
faster, and if you pull the plugs it's easy to turn the crank around
by hand. TD engines do make a lot of tappet noise, but in many cases
this is the result of very bad tappet and cam wear (as it was with
mine). The alloys available when the engine was built were amalgams
of old flatirons, refrigerators and the odd Messerschmitt blown out of
the sky, so wear is a very bad problem.
Tappet clearances (specified in the shop manual, something like 0.012
for the intake and 0.018 for the exhaust) should be set with the
engine hot (but off). I would urge that you take the side plate off
the engine and take the rocker assembly off (perhaps half an hours
work) and pull the tappets out and look at them. Mine were pretty
badly chewed up (at 85,000 miles), and the cam was not in good shape
either. Cams are available (from Crane), replacement takes about a
day (no need to pull the engine), and the up side is that your engine
will run much better. Tappets should always be replaced with a new
cam.
A. B. Bonds
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