by RoadMaster75 » Mon Jun 02, 2008 9:48 am
HI
Sorry for the delay here, but I've been off on other projects.
A "knock" that goes away may in fact be timing or gasoline related.
If you are one of the unfortunate ones who lives in a "reformulated"
area then gasoline quality is a growing problem for owners of old cars in general.
Ethanol only adds to the problem! I recently bought a 455 1973 Buick from
rural wisconsin (they get 100% gasoline up there). I brought it home to the Chicago area & after only 3 tankfuls of
"reformulated/ethanol" gas, ALL the short rubber connecting hoses from the gas tank
to the steel fuel/evaporator lines sprang leaks. They all looked fine
on the outside, but after cutting them open the inside surfaces were like
black bubble gum! We old cars guys MUST be vigilant on these
fuel vs. old rubber issues! Be watchful of carbs & fuel pumps, too!
After that little episode I put my 58 Roadmaster up on the lift and replaced the entire fuel
line with new steel tubing and all the rubber connecting bits. We must use
SAE rated fuel line for fuel injection to get the correct material that is
impervious to these new (inferior!) fuels and additives.
Check you timing/advance mechanism & make sure that you use good quality fuel
and it never hurts to throw in a bit of octane booster!
regards
Mike
1958 Roadmaster75 - Unrestored w/ 40,000 orig. miles
1949 Willys-Overland Jeepster - Buick V6 power
1951 Chevrolet 1/2 ton Panel truck - 455 Stage One Buick power
1978 Cadillac Eldorado "Biarrtiz" - 22,500 orig. miles