Holley 4150 Rebuild/Jetting

Started on the carb rebuild and here's what I found - the jets in the primary metering block side are not the same jet number - one is an 84, the other is a 75 in the same metering block!...I had read in the red Holley rebuild handbook (one of the 4 "bibles" I''m using) that on "RARE" occasions there are two different jets on the "same side" - but I was curious so I broke open the secondary metering block and looked at the jet #'s and low and behold - one's an 84 and the other is a 75...hmmmm...is this one of those "RARE" occassions or is it more likely the last person to rebuild this carb was smoking crack and mixed the jets up...hmmm...

What is conventional wisdom and then step two, what do I do - logic says that the same jet #'s go in the same metering block - so do I put the 84's in the primary side and the 75's in the secondary....

Bear in mind, this boat HAS been running like this for the two years I've owned it...I just don't know jack about jetting carbs - anyone want to take a swing at this one?


Wes

75's in the front 84 in the secondary. The spark plugs should have a light brown color to them. White on the inside is to lean and you need bigger jets. Black on the inside of the plugs is to rich and you need to down jet.

Hey Aaron,

Sounds like a plan, thanks man


Wes

The screws on the metering plate should be ajusted as well. Do one side at a time. Screw it all the way in. The motor should stumble and try to die. Then quickly unscrew it so it does not die and stop when motor has reached it's highest idle. If the motor does not stumble or try to die more than likely the primary jets are to big. The best way to jet it is on the water. Start the boat let it warm up. Then go out and make a hard pass 4500 to 5000 rpm's and then shut it down do not let it idle. Once you shut it down pull the#1 plug and check the color. Most Holley's idle rich and people tend to think it needs to be jeted.

Hey Aaron,,Thanks again for the tuning tip - it runs like a raped ape! Idles smooth, no lag on acceleration, I'd say it was a successful rebuild.

I do have a small fuel leak at the fuel line fitting - the one that tightens into the fitting with the small fuel filter in it - it's tight (and a REALLY don't want to strip it out!) but does weep slightly - looks like the previous folks used some sort of pipe dope/compound - got any sage advice for this? Will teflon tape react with gasoline?

Thanks again for your tuning help - if you're in Annapolis, come on down for a pull

Wes

I have used teflon tape and had no problems.
Thank's for the offer but I live in Houston,TX.