Jason,
Since I don't remember from your original post what kind of MG you have, I'm
assuming that you have one with a 2-piece crank pulley. These serve as a
vibration dampener as well, having the outer ring bonded to the inner via a
rubber insert. Over time, the vulcanization can break down, resulting in the
outer ring slowly moving relative to the inner, with the result that the
timing mark is no longer where it should be.
The short term solution is to bring numbers one and four pistons to the top
of their stroke (viewed through the spark plug hole and confirmed by resting
a small screwdriver on the piston crown and feeling for the top-most
position). Then mark the edge of the crank pulley with a new mark against
the TDC pointer on the timing cover. Now you can re-time your distributor to
fire when number one is at TDC and the two rocker arms for number one
cylinder are not in contact with their valve stems.
The long term solution is to buy a new crank pulley, as the one that has
already moved will probably continue to do so.
New valve cover gasket? Yes, if the old one breaks when you remove the valve
cover or if it excessively crushed or brittle. They're not exactly expensive
so you should always have a spare handy if you're planning to remove the
valve cover.
Lawrie
British Sportscar Center
----- Original Message -----
From: Jason B Lonon <j_lonon@lycos.com>
To: <mgs@autox.team.net>
Sent: Monday, January 15, 2001 9:15 AM
Subject: timing quandry (was engine not cranking)
> Thank you to every one who responded to my note about the engine not
cranking. I got so many replies I couldn't possible list everyone. (Over 15
replies.)
> Let me run over a couple of things that were suggested, and the result of
trying them.
>
> 1) Some people asked about the type of carb I have. Its a Weber DGV
conversion.
>
> 2) I have checked the fuses, in fact I replaced the fuse box just because
the one it had was grungy looking. I have cleaned all the battery cable
conenctions so that they are shiny.
>
> 3) I do not see any cracks in the distributor rotor cap or any black
streaks.
>
> 4) When I replaced the starter, I did take off the distributor. After
re-installing it, I have, to the best of my ability and knowledge, re-timed
it statically.
>
> So, today, I went out to change the spark plugs. (Someone suggested that
perhaps they got fouled up from being flooded.) When I had them removed, I
decided to turn the engine over by hand just to see inside (After
eliminating as much as I have, it seems that timing is still a possible
problem.)
> After doing this, I was confronted with what my novice mind interprets as
a quandry. When I timed it the 1st time, I used the timing notch on the
pulley at the front of the engine. However, what I see is that NONE of the
pistons are close to being at the top of their path. The 1-4 are at the
bottom coming up, and the 2-3 are heading back down. So now I'm baffled
according to what I thought I knew. I thought TDC was when the #1 piston was
at the top of it's compression stroke. But if that is the case, then my
timing will be nearly 90 degress off of the timing notch on my pulley.
> This is the first time I've timed the car, as I said, I just bought it a
few months ago and it had this breakdown a few days after I got it... so is
it possible that the pulley is wrong, or is their bigger problems?
> I tried to time it based on what I saw the pistons doing, but it still
didn't fire up.
> I've read on here the only way to be sure you are at TDC is to take off
the valve cover and look at the valves. Will I need to replace the valve
cover gasket when I do this? If so I had better order one before trying.
>
> Cheers!
>
> Jason B. Lonon
>
> ---
>
>
>
>
>
> Get your small business started at Lycos Small Business at
http://www.lycos.com/business/mail.html
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