86dually454

Hi, I am new to this forum. I own a 1986 C30 Dually with a 454, edelbrock intake and holley carb. It sat for a while, but ran great before sitting. Carb gummed up, so had it rebuilt by reputable shop, has ran great for the last two weeks. Had it idleing out front for maybe 3-5 minutes while I was working on radio, and engine kind of sputtered and almost stalled, caught itself, then almost stalled again so I shut it off. Temp gauge was fine etc. Restarted, and there is a bang/knock/sound coming from it seems like under the carb inside the motor. Had my Dad listen and he thinks it may be timing chain issue. Will start and run, but makes the noise and increases with acceleration, so I don't want to drive/damage anything. Not a tapping, lifter type noise, more of a bang from inside motor. In the end I will probably take to a mechanic, but was getting ready to sell and really didn't need this headache. I guess I'm asking for any opinion and typical cost associated please, I'm located in Phoenix az if that helps. Or any experience with cost of buying a junk yard 454 and replacing (big dice roll) versus repairing this one...Thanks for any help.

Allan In NE

Big blocks have a nasty habit of throwing rockers. You might want to pull the covers and check that first.


Allan