The problem: My '59 MGA 1500 has been fouling sparkplugs like a bandit.
The problem seems to be getting progressively worse. got about 1000 miles
off my first set and have gone through 2 sets in less than 1000 miles. It
seems to be oil fouling in that there is oil on the plug threads. The engine
misses and I can feel a definate whap-whap-whap coming out the tailpipe.
The #4, #3 cylinders seem to the worst but also in #2 and #1. My dad
rebuilt the engine about 15 years (<2000 miles) ago and it sat all that time
until this last spring. The rebuild head work included grinding the seats.
Compression is a bit high but even (165-170 psi on all 4 cylinders) - maybe
due to the carbon buildup. It doesn't smoke a lot but I can sometimes see a
very fine cloud of white smoke on acceleration.
Remedial action: I've adjusted the valve clearance (no diff), used top end
cleaner (temporary improvement), switched plugs (problem clears but then
returns) and adjusted the carbs. According to my Colortune, the rear carb
runs rich in spite of my efforts to adjust it but the motor doesn't speed up
when I lift the piston. A more experienced person than I has seen my used
plugs and said they were oil fouled. I've also checked plug wires and
replaced the first one - no difference.
Proposed cause & remedy: I believe the problem may be due to breakdown of
the rubber valve seal gaskets and plan on replacing them. I am prepared to
pull the head but am hesistant to do so as it seems tight now and I hate to
disturb something that is apparently working fine. OTOH - I may be suprised
by what I find if I pull it.
The question: Can I replace these without pulling the head (eg. using
compressed air or clothesline fed into the cylinder through the spark plug
hole to hold the valves in place)? What are advantages/disadvantages of
pulling/not pulling the head ?
Thanks much
Ralph Cordell
rzc4@cdc.gov
Hospital Infections Program
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