Hi,
I've been lurking for a while now, but feel prompted to
introduce myself due to a perplexing problem that I'm
having with my '66 MGB GT.
I bought the car a few months ago. Not because I have this
rose coloured vision of how good british cars are; but
because I like the simple things in life. I think that it
was only natural for me, as I enjoy riding classic motorcycles,
and have found with simple preventive maintenance they are
as reliable as their modern counterparts.
Anyways, on to the GT. As I have already said, it is a '66
MGB GT in BRG with 78,000 miles on the clock. The engine
had been rebuilt by a local british car dealer. Overall the
car was mechanically good, good interior and a 20 foot paint
job. There were things that needed work to bring them up to
scratch. It was the best all around condition GT that I'd
seen in the last few months. I particularily wanted a GT over
a roadster as I intend to use it all year round. When the
temperature is -30C outside it is nice to have a roof over
ones head.
So for the next few weeks I worked on addressing what state
the car really was in. Who needs a social life when you have
a british car? I changed the oil, adjusted the carbs, topped
up the gear box oil, adjusted the carbs, lubicated the front
suspension, adjusted the carbs, rebalanced the front wheels,
adjusted the carbs, reset the valve clearances. The observant
amoungst you might begin to notice a pattern in the work that
I was doing on the car.
You see I could get the carbs perfectly synchronised if I
wanted an idle of 1500rpms. The damn rear carb justed wanted
to suck more than the front. It refused to operate below
1500rpms. With the air filters off you can see that the height
of the rear piston, at idle, was greater than the front by an
1/8 of an inch or so. No matter what I did I couldn't get the
height of the piston to drop down. I twisted all the twiddly
bits I could, but it still wanted to be superior to the front
carb.
In the mean time I racked up a few tentative trips to the
mountains on a favourite road of mine - discovering that if
you have the rear tyres 3psi more than the front, it handles
*much* better. I stored away in the back recess of my mind
that the front was under damped and the rear over damped which
makes for some interesting steering wheel manouvers on bumpy
twisty narrow roads at high speeds. Well I wouldn't say that
they were that high - it just feels like it in a car that is
low to the ground. In the twisties, a modern car driven by
an old lady would leave me for dust (if she had balls %).
I'd get to my destination with a grin. The car is so much
more fun to drive than any other car that I've owned. I
used it as it should be used (and as it was designed to be
used). It is nearly thirty, but I have little respect for
age.
If you are still out there reading this. I'm sure that you
realise that there is a punch line somewhere along the way.
Well this is it. One day I was tootling along (in the city)
and started to hear a knock. Yes the knock is definitely
coming from the engine. This is bad news(tm) I think. Sure
enough, the best advice told me that it was most likely a
rod bearing, but could even be a main bearing. So I did what
any self respecting person would do. I paniced. I'd just
owned the car less than a month and I'm about to do major
surgery on it.
There were a couple of choices - do the work myself or
farm it out to the british car place. My chequebook said I
had to do it myself. I decided that I would drop the pan
(lifting the engine up from the front to give me enough
clearnace to remove the front pan bolts - I used a jack
and a block of wood under the rear pan). Sure enough, one
of the connecting rod's big end bearing was shot. (#1 cylinder
for those keeping statistics on these things),
For those of you who are contemplating doing this at home,
I'd highly recommend it. With the right tools and relaxed
frame of mind, it is a straight foward job.
The one thing I didn't know, was why it had failed? Another
thing that I found bothersome, was that the crank is already
30thou undersized! That means, I have one undersize left to go.
(Time to look for a possible donar motor.)
Well, this last weekend, I'd collected all the parts that I
needed. And set about putting all the pieces back together
again. I took my time and double checked everything. Just
to be clever, I put it all together once, sealed everything
up and *then* decided to double check it one more time. So
everything came off again. Rechecked and then put it back
again. Even after all this, I did not have *any* pieces left
in the plastic tubs that I was using to store related pieces
together, nor did I discover any tubs that I had forgotten
about.
When I was putting it back together, I discovered that on number
one cylinder, the big end cap's punch marks did not line up
with the punch marks on the connecting rod. Well it did if
you had the cap on backwards. By george (or whoever the
previous owner was), I think I might have discovered why number
one failed.
After it was together, and her fluids restored, I primed the
oil pump (which took ages) and then fired her up. Everything
was in order, no displace fluids appearing and no knocking. The
only thing is that she still idles at 1500rpms...
So we now come to my question to you. How can I her to idle
at say 800rpms? I've recentralised the jet, adjusted the
mixture, idle screws, but the rear carb's piston is still that
1/8inch higher. The carbs are SUs with the remote floats if
that helps.
advTHANKSance
,
"A storm breaks trees, Mark -%)
it only bends grass." msw@cpsc.UCalgary.CA
Solzhenitsyn ...!{uunet!ubc-cs, utai}!calgary!msw
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