problem with my 383

[cak1983]

Im hoping someone can help me with my motor. It makes a loud popping noise out of the carburator every 2-3 seconds when idle. The timing is set to 32 degres at 4200 rpm.the motor is a 383 w/2.37 gear box. thanks for your help.

 

[Joe]

Sounds like a valve problem,does it go away when you rev it?

 

[cak1983]

when i rev the motor it gets louder. when i feel the carb it feels like im taking a hammer to it.

 

[cak1983]

i do need to adjust my lifters there nocking a littlt bit. i just put my motor together

 

[Ol Yeller]

Might be a head gasket problem. If the head gasket is gone between two cylinders the spark from one will ignite the fuel in the other causing backfiring out the carb. Run the engine at night and look for fire coming out of the carb. If you see fire do a compression test. Good luck and let us know what you find.

 

[cak1983]

i took the scoop off the carb and i dont see fire its fuel when i rev

 

[cak1983]

just remember every thing is brand new

 

[bondsman]

had that problem with my caddy once and it was a busted valve spring.i am glad i cought it before i dropped the valve.but i am not saying that is what it is just similar.

 

[Waterthunder]

Sure sounds like you have an intake valve to tight! How did you adjust the valves?

 

[cak1983]

i took the valve covers off and inspected everything i didnt see anthing wrong visually.i bought cheap aluminum heads off ebay and if somthing is wrong with them im going to deffenitly shove them up there a$$

 

[cak1983]

I set the timing at tdc. and found a spec sheet off the net of which valves to adjust. tightened them down until there was no play in the push rods and 1.5 turns on the nut. Then i turned the motor over 1 time and did the rest of the valves

 

[cak1983]

This is my first motor build and i kind of went over board with every thing.I learned pretty much every thing from this forum and I really thank everyone for trying to help.

 

[bravo1218]

check your plug wires.you might have 2 of them crossed

 

[cak1983]

i just talked to a friend and dave is right i tightend the valves to tight and there not closing all the way I double checked them and when i adusted the second time the lifters were not primed and thats what caused it thank so much for all your help ,chad

 

[Waterthunder]

Cool I'm glad you found it and it didn't cost you a dime. A little hint anytime a bran new motor pop's out the carb it's almost always the intake valves are too tight. 90% of all hydraulic lifters work off of a .050 lifter preload!