Holley Carb Blues

[TollyWally]

I appreciate the input gentlemen,
With any luck I'll get to the boat Sat. Morning. I'm ready for a test run but I need a buddy to run along side me in case things go bad.
I've adjusted the float level and checked the seconday power valve gasket.

Par,
That is not my carb. Mine is a holley 4100, a spreadbore patterned after the Rochester. It does not have the detachable float bowls like the one you have a picture of. The top of the carb comes off and both float bowls are revealed.

Again I appreciate the input and will be seeing what there is to see Sat. morning.

Carbs seem to be my special nemisis right now. I am helping a guy who keeps his boat at the same dock with his carb problem too.

[Jimbo1490]

That sounds like a 4100 Motorcraft/Autolite, NOT a 4100 Holley. That's actually a better carb than the 4100 series Holley. Does it look like the one I linked?

Darn confusing that they have a similar model number, huh?

Jimbo

[TollyWally]

Jimbo.
This baby is a holley. It is the stock carb on a mid 90 Volvo marinized BBC crate motor. The top comes off like your picture but it has the needle valve adjustments for the float level on the top at each end. The fuel comes into the float bowel high. Choke and vacuum advance for secondaries is a little different. Despite my best intentions I didn't make it Saturday. Hoping for tomorrow.

[PAR]

It sounds like the Holly casting of the Quadra-Jet (they bought Rochester), which I don't have an image of, but know the carb.

[TollyWally]

Interesting Par,
I knew that it was patterned off of the Quadrajet but I didn't have any idea Holley had bought them out. Somewhere In my research travels I've seen mentioned that the base bolt pattern or whatever? matches the Quadrajet flange pattern. I don't know much about Rochesters (or any other carb for that matter ) but most of the other features like the fuel line location, float level adjustments, float level sight screws look like pure Holley to me. But who knows. I learn a little something from each guys input, thanks fellas. I'm headed for the boat in about 2 hours, hoping for a little luck.

[PAR]

Two Rochester carbs, both automotive, but similar, except for marine upgrades. Electric choke on the left, well tube, mechanical on the right.

It's an easy carb to work on, tune and rebuild.

[thudpucker]

Good photos. I had three GMs with Q-jets and liked them.
My work partner had a 65 SS that burst into flames out on the freeway. The FD said it was the Q-jet. Must have been one with those flimsy rubber diaphrams.

[TollyWally]

Thanks for the photos Par,
My Holley doesn't look much like those carbs except for the spreadbore similarities.

I pulled the top yesterday and double checked the float hinges etc. The fuel in the bowl looked suspicious. I'm beside myself with irritation over that fuel, I have less than a half hour on the multiple filters in the system. I tore the gasket on the top too. It is new but I have had the top off several times. She started fine and idled ok for about 15 minutes. Today I am going to mount a kicker motor, if that works out I'll test her under load and be able to make my way home if things run amuck. Again thanks for the input and wish me luck boys!

[Jimbo1490]

TollyWally,

I don't recall ever seeing a Holley carb that had a float cover as you describe rather than float bowls mounted on the ends. Holley has purchased several carburetor manufacturers over the years, so this may be another manufacturer's carburetor wearing a Holley badge.

PAR,

You have a 4M and a 4ME there. The last several I've rebuilt were the newer M4ME with the APT metering circuit. Those Rochesters were near the pinnacle of carburetor development. This is partially why GM switched to EFI so late; they did not need to make the switch because their carbs, unlike many others, actually worked well and met the newer emissions standards. They are much easier and less tedious to tune to a given engine than the Holleys becuase you don't have to keep changing jets, just move/change the metering rods.

The carbs on the 80's Hondas were notorious for their overcomplexity and ease of going out of whack so that the car would fail a smog test, despite the engine being sub 2 liters displacement.

Jimbo

[TollyWally]

Well got the kicker mount installed and the kicker in place. Tomorrow fresh fuel for the kicker, if she runs then out for a test on the big boat motor under load. I'll try to upload a pic of my carb.

[El Sea]

TollyWally,

Sounds like ethanol.
We clean fuel tanks daily and currently every boat that we have serviced has had what I refer to as being 'ERI', Ethanol Related Incident. Pumping out the old fuel and replacing with new will not cure the issues. You need to remove all of the sediment from the tank and treat the fuel before the phase separation takes place and before the ethanol attacks your fuel system components. Ethanol love to destroy rubber, plastic, o-rings and pumps.

Luther Carrier
www.absolutetankcleaning.com

[PAR]

I'm seeing the same thing and suggested so in an earlier post. I'm getting a fair amount of work from ethanol.