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Gm 5.7 backfires and pops

boatingfun1

Contributing Member
Hello, just got the motor gm 5.7 350 rebuild. Rebuild the carb. Readjusted the valve rods. When i go to test start motor on a stand i build. It back fires through exhaust and pops through carb. Crank no start. Check fire order and timing all good.
please help.
 
did you buy a complete rebuilt engine or just a long (or short) block?

how did you "Readjusted the valve rods."???


 
did you buy a complete rebuilt engine or just a long (or short) block?

how did you "Readjusted the valve rods."???


I got the boat i rebuild the engine with what it had. I put new gaskets, piston rings. Rebuild carburetor. Didn’t wanna put new cap and rotor and wires yet till i seen it start up.Wish i can upload video of starting it up. Some reason wont let me.
 
you can't upload videos to this board...only links to it, if you post it elsewhere...

I'd be inclined to back off the rockers and then readjust them with it running...
 
Got it to run!! Fuel pump keeps loosing prime. Using a electronic fuel pump!
Any recommendations for a Electrical fuel pump for the GM 5.7 350?

Thank you

Eric
 
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