1972 Other Chevrolet Models BBC

JOSHREYNOLDS777

MEMBER
1972 CHEVROLET

1972 Other Chevrolet Models V8

Thanks for the help in advance.
I have a 454BBC in my 72 jet-boat.
The starter went out, so we replaced it, the new one's cast cracked.
The 2nd new starter, seemed just fine until we hooked up the spark plug cables and cranked up the fuel pump.
after that the engine seemed to be really binding, or resistant, missing, blow off sounding backfires, and just very loud, tired sounds coming from the starter.
we checked the compression, and its fine. Doesnt seem to be any major engine component issues.
once we unplugged the spark plug cables, the starter turned the motor over and sounded fine.
So, are we thinking timing chain issue?
thats all i've got.
If so, I dont know if I can get the harmonic balancer off with the amount a clearance I have to the deck.
so, engine pull?
and check/replace timing chain?

thanks for the time

Josh Reynolds

936-443-3252
joshreynolds777@me. Com

1 Reply

HMAC300

MECHANIC
48,601 POSTS

If your timing chain is bad your compression should be low. Like 75-90 p.S.I. On all cylinders. Another way to check is to bring the #1 cylinder up to TDC. Then pull the distributor cap ff and see where the rotor is pointing. #1 on the cap is about 11:30 on a clock with 12:00 being the very front. If it's off alot then it's probably a chain. This could also have th timing just out of adjustment, especially if youhave the spring type holdown for the distributior. As they would spring and let the distributor go out of time and do what you are sayng. YOu can easily replace thespring type with a regular holdown form a small block or big block they are the same.