Carb Adjustment???

[ken0275]

My 76 Bronco finally made the trip here from South Carolina. I am pretty happy with it so far.

I have discovered a couple of problems, like the leaky aux. tank and the truck runs very very rich.

So is there an easy way to or tried and true method to adjust the factory 2 barrel on the factory 302.

I have receipts from the previous owner and the carb was rebuilt in the last few thousand miles.

I am sorta afraid to mess with it, since all you have to do is tap the key and she fires right up.

But the fumes are terrible and she spits out black water from the tail pipe. I know the water is mostly condensation from sitting. My garage door looks like an abstract painting. Even driving down the road the exhaust is bad.....I feel bad for the cars behind me.

 

[oleguy74]

possible power valve.or just float adj.

 

[ken0275]

How do you do that????

I am like Sgt. Shultz from Hogan's Heroes........."I know Nothinnnnnnng!!!"

 

[Seabronc]

How do you do that????I am like Sgt. Shultz from Hogan's Heroes........."I know Nothinnnnnnng!!!"

If you know nothing, and it otherwise is working great, I'd go to someone who knows what he is doing. The other option is to learn about your carb. If it is a Holley then you can get books on the subject and dig in. Assuming you have relatively good mechanical ability, it is possible to bring yourself up to speed. No matter what, correcting the problem may be a bit of tear down and reassembly. Running rich after a rebuild, assuming no major problems exist in the carb, could require changing the jets, float adjustment or like previously stated the power valve may be blown so it would need replacement. With the exception of the float adjustment, you will need to do some disassembly and reassembly.

So what I'm really trying to say is get a local professional opinion first. Unfortunately we are not in your garage to look at it and walk you through the process. Find out which carb it is and then read up on it. It is not all that difficult, but the process is too much to include in a forum post, so first you need to determine what is wrong and then go after that and not, "shot gun" the problem. I don't know how we could do that remotely. We can give you suggestions of what may be the problem but we aren't there to actually see and diagnose it.

Good luck,

>-

 

[Bully Bob]

Ditto above.., and.,

"I have receipts from the previous owner and the carb was rebuilt in the last few thousand miles."

Sorry., I would have to question this..... /emoticons/[email protected] 2x" width="20" height="20" />

"tried and true method to adjust the factory 2 barrel on the factory 302.?"

Not for what you're experiencing. There's something internally wrong in that carb.

"...she spits out black water from the tail pipe"

Not to scare you., but this is probably/could be early signs of a head gasket failure.

All in all.., a great start...!

BTW..., which one R/U selling...green one or red one...?

 

[ken0275]

Ditto above.., and.,
"I have receipts from the previous owner and the carb was rebuilt in the last few thousand miles."

Sorry., I would have to question this..... /emoticons/[email protected] 2x" width="20" height="20" />

"tried and true method to adjust the factory 2 barrel on the factory 302.?"

Not for what you're experiencing. There's something internally wrong in that carb.

"...she spits out black water from the tail pipe"

Not to scare you., but this is probably/could be early signs of a head gasket failure.

All in all.., a great start...!

BTW..., which one R/U selling...green one or red one...?

I know a good mechanic and I will let him look at the carb. It only spits the water out while I am warming up the vehicle. It doesn't do it after its warmed up. I figured its just condensation from the drastic temp changes from the day to the evening. I may only start it on the weekend, during the week it sits.

I will be selling the green one. Red/ copper one is the one I just purchased.

How much of a difference does it make to a carb if it was rebuilt in Florida and dialed in there for their humidity and sea level. Now the truck is near Chicago.....Could that make that much of a difference???

I would think that would be the case if the truck came from Colorado......I would assume a truck would need to run richer in higher elevations.

If I have to buy a new carb it will be no big deal.........

 

[Bully Bob]

"How much of a difference does it make to a carb if it was rebuilt in Florida and dialed in there for their humidity and sea level. Now the truck is near Chicago.....Could that make that much of a difference ???"

None..., & there's no "dial-in" for humidity.

Sea-level to approx. 5000 ft. req. one size "jet(s)" ---above req. a smaller jet(s)..as a rule of thumb.

"I would assume a truck would need to run richer in higher elevations."

Actually.., the opposite is true..., the higher up ., the thinner the air., therefore., the carb needs smaller jets to bring the ratio nearer to the req. "17.4 to 1" (or is it 14.7 to 1...?) :wacko:

(BTW.., "jets" are what meters the "fuel" ...not the air.)