Carb question

[trularin]

I recently took my car out for a ride to work.

It ran fine. Went to lunch and sprewed Black smoke. And, all the way home it spewed black smoke. There was an assortment of misfires, pops and very strong burning fuel odors.

As it was I went through about 6.5 gallons of gas in 33 miles. And I was not getting on it. There is NO gas spewing out the vents as a stuck needle and seat might suggest. It does have forty year old brass floats.

So, the carb is a older 3310, 780 CFM on top of my 358. When running right, this engine does very well.

I was wondering if those of you that may have had more than your share of experience could suggest what might be the problem.

I was thinking the power valve is stuck just a little before closing or the floats are sinking and the fuel bowl level is very high.

Any help would be appreciated.

[Excaliber]

The symptoms suggest a stuck needle valve or bad float, more than a blown power valve. All though, with all the backfiring you could have blown PV now! I'd tear it down, get a kit and rebuild it at this point. "Rebuild" on a carb is often nothing more than a good cleaning, you may not even need a carb rebuild kit if the gaskets are good. Check the floats for binding or being 'heavy', check or replace the PV, blow out all the holes you can with compressed air/carb cleaner, adjust and go.

[tcrist]

The choke could also be sticking closed and choking itself out. If I take apart a carb I replace all of the gaskets just to be safe. I dont know what brand of carb a 3310 is but if you backfire through a Holly there is a very good chance you blew out the power valve now like Excaliber said. At least that is the way it was with the old Holly's.

Terry

[trularin]

Ops. a 3310 is a Holley. Sorry.

So far, the power valve looks like it has been attacked by acid. Never seen anything like it. I can only believe the needle and seat are scrap as well.

[wtm442]

You can always go back to "Wolfie" power!

Did you find any brass floats?

[Excaliber]

One of the things I've found on older Holleys is; it's real easy to strip one or more of the four bolts/screws holding the fuel bowls to the main body of the carb. What I do is tighten them 'just enough' to feel good and I EXPECT them to leak a little when the carb starts to fill with fuel. At that point if they DO leak I tighten them up 'just enough' to stop the leak. Then keep an eye on them for a few days to make sure you got them just tight enough, but no more! New gaskets on the fuel bowls can be purchased separatly and is really worth the money if it helps to avoid stripping those bolts/screws!

Sounds like a complete rebuild kit might be the way to go on yours from the description of the PV.

[trularin]

All is in vain, as I was looking over the carb, we found the passenger side pipe was cracked and there seems to be a number of other issues. Thanks for the advice.

I think the season is over for the Cobra.

Yes, brass floats are at three different shops.

[Excaliber]

Season is just getting started!!! Get some 'muffler wrap' for those headers, buy a new carb, put bandaids on the rest of the problems and try make it to winter.

[wtm442]

Tru's a wimp. The season is NOT over until the snow sticks to the ground and accumulates. FIX IT! Or Turtle and Frenchy will pay you and Wolfie a visit!

[trularin]

Side pipe is broken. It will have to be rewelded and sent out for ceramic coating.

The carb appears to have a crack in it.

There are other issues.

I appreciate the support, but this is a matter of cubic dollars and unavailable time.

[Excaliber]

Boy I know how that goes! But they say half the enjoyment is working on them anyway.

[wtm442]

A day witout a Cobra ride is like
A day without sunshine.



Just had a thunderstorm pass thru about suppertime. Power was out for 2 hours. At least it did not rain like it has in TX.

[Ron61]

Tru,

Sorry to hear about all the minor problems that you have which have added together to become a real problem. If the carb is cracked, I would just replace it with a new one of the same type. I am guessing the other issues are not major. When I had my carb built and dynoed in Los Angles, the bank was very nice about loaning me the required money. When I sold the car I paid the loan off.

Ernie,

If 50% of the the enjoyment is working on them, 75% is frustration with them, and another 32% is just getting disgusted, why not throw out the working on them.

Ron

[GASKETBOY]

Tru,

I've got a Rubbermaid tote full of Holley carb bodies. I'm pretty sure there is a 3310 or two in there. What part of your carb is cracked?

I'll look for it and if I have it then it's yours.

Jeff

[blykins]

What a great bunch of guys...

[Jerry Clayton]

Trularin

Is it the main carb body cracked or is it the very common broken base plate? A broken base plate will give very serious vacume leaks and backfiring

Most of them are broken by over tightening the carb to manifold, especially when using spacers to isolate the carb from manifold heat

Jerry