Hey truckers, I have a 1968 Ford F-100 with a 390. I changed from edelbrock 600 w/ manual choke to an edelbrock 650 w/ electric choke. I was riding without the choke hooked up but later hooked it up because my truck was smoking EXTREMELY bad. I was hoping the choke being hooked up would end this, but it didn't. I can't figure out why my truck is smoking so bad...I also have a 6-8 psi electric fuel pump...could this be the problem?

 

I guess I should add that it smells very rich and no matter how much I turn the fuel back on the carb it stays rich...and the smoke is blue

 

Blue smoke means oil burning. Manual fuel pumps work just fine . Your electric pump could be pushing to much fuel into the carb causing you to burn to rich all that gas washes the cylinders down and the rings cant seal hence the blue smoke

 

Is the 650 new? If not do you know its history? If it started smoking when you put the 650 on, then maybe it is the problem. Was there something wrong with the 600? Maybe you should switch back. You could try a kit.
A new carburetor has solved the problems for me more than once, and it is a relief once you have one.

 

The 650 came from my girlfriends dad, he races dirt track cars. It came off a 351W. It was running like a charm on that, the 600 had a lot of problems. My truck would not run at all with it on there. I switched to the 650 and it runs fine. It's just smoking very heavily

 

@akforceten that makes a lot of since...in going to look into that

 

put a in-line fuel regulator and set it @ 2 and 3 psi max i had a 700 with a cam and it did the same thing to me put it on and ran better then ever with anything more then 3psi will push the metering valve out of the way

 

I'll look for one of those then, thanks

 

also the 650 may be jetted wrong . there is a huge difference between jetting a carb for street driving an racing may need to rejet the carb. if there were any changes made .

 

I don't think the carb was tampered with. The guy that had it to me said he ran it one then switches to a Predator 1100 box carb..he ain't a fan of edelbrocks lol

 

I love edelbrock carbs there a great carb for the street very easy to tune!

 

I like em too