Well, wise ones, I had a little bit of a scare today in my B, and I
thought I'd see if anyone had any further suggestions beyond what I
attempted.
FYI: 66 B roadster, stock carbs (with Grose-Jets) and exhaust, Allison
opto-electronic ignition, 5-main engine of unknown internal configuration
(used Gold Seal unit acquired from wrecker)
I drove up to Berkeley in the late morning -- 50 miles, all freeway,
60-70mph, ambient temp around 75, I'd guess. Once in town there was
fairly heavy traffic, so I had to wait at each stop light, but the temp
gauge was stable at just over 190, oil pressure just under 40 at idle.
Then I got stuck behind a double-parker for a couple minutes, and when I
finally got a gap, and tried to shoot out, there was a very loud "bang"
(like a backfire or exhaust explosion) and I lost power. After two
smaller bangs and at least one puff of black smoke, the engine quit. I
coasted around a corner and up a driveway onto the sidewalk, since the
block was entirely red kerb, and the sidewalk in front of the Firestone
dealer was very wide, and full of parked motorcycles, anyway.
Turning the key, the engine cranked but showed no sign of starting
(usually it catches on the first or second crank). Never having
experienced such a dramatic explosive effect, I wasn't sure what to look
at first. The distributor hadn't rotated noticeably and still seemed
tight. I took the cap off and the little optical sensor jobber was
intact. The plug wires were still attached. Oil and water were fine. No
drips underneath (ah! that must be the problem! <g>). The fuel filter was
half-full, as usual. I thought to take a look at the spark plugs for
clues but my tool kit did not contain a spark plug socket (I seem to
recall pirating it at some point, and I guess I forgot to replace it. Bad
boy!).
>From the phone booth on the corner I placed a call to Mike O'Connor at
O'Connor Classics, my MG specialist. His mechanic, JR, suggested looking
for a fuel float problem, possibly flooding. I wasn't too sure about this
since the fuel pump hadn't been ticking while I was cranking it, and
there was no overflow on the ground, but I followed his suggestion to tap
on the float bowls to possibly unstick the floats, using the handle of
the knockoff hammer. Then, since my destination was only one block
further on, I left the car basking in the sun and went away to take care
of business for 15 or 20 minutes.
On my return I tried cranking it again, and it almost caught. Then, on
the second try, it fired! By this time the temp gauge had gone down to
around 130. I decided to see how it ran, and look for a better spot to
tinker with it. I drove about 5 blocks, with it sputtering and missing,
and found a Kragen's parking lot, where I snagged the last slot (popular
lunch place?). There I removed the float bowl covers and blew out the
jets. Nothing seemed to be particularly wrong wih them. I gave them a
good shake, anyway. With everything back together, I started it, and it
idled OK, though a bit rough, and under the hood I could hear a faint
"tick" that sounded rather like an electrical spark. Reaching around the
distributor cap to feel for loose wires, I felt a small shock. I shut it
off, and found that one of the plug wires had totally fallen off the cap.
I had checked these at the previous stopping place, but I had never been
overly satisfied with the fit of this particular set. At any rate,
starting up, it seemed to run perfectly, or as well it ever does, at
least. I drove home the long (but less jam-ridden) way, 80/Bay Bridge/
280/El Monte, at 70+ mph and 85 degree air temp, without further mishap.
Sorry to bore you with all this, but what puzzles me is, what went wrong?
and how did I fix it? As you can see, the evidence is somewhat
"contaminated"...
--
Max Heim
'66 MGB GHN3L76149
If you're near Mountain View, CA,
it's the red one with the silver bootlid.
|