3310 Random stalling

[71_Duster]

Having an odd intermittent issue with the 3310-S on my 440.

I killed the trans in my daily driver so the Belvedere has been my DD this last week. Lately when coming to a stop (panic or normal) the idle drops and will just about stall unless given some throttle. I just put a hydroboost set-up in so I figure I'm more aggressive with the pedal now. Last Friday I turn off the main road normally and it just dies in mid turn. Coast to the shoulder and doesn't want to start like it has no fuel. Cranking and pumping then it fires up.

I pulled the front bowl off everything looks ok, vent baffle in place no debris, floats seem good. Bowls back on checked the float level just barely trickles out when running.

Go for a drive and all seems well then back to its tricks again. I've started the habit of shifting to neutral when at a light so it doesn't shake so bad. Idling away happily in neutral and it just shuts off. Doesn't want to start like it has no fuel. Eventually after cranking and pumping fires up like nothing happened.

All 3/8 fuel line, new filter, almost new edelbrock mechanical pump. Idles @850 in neutral 650-700 in gear. Newer firecore distributor, plugs, wires, etc its defiantly not an ignition issue and its intermittent. If it was just when I was braking or cornering it would be more understandable but while idling in neutral and stopped?

I keep looking for an excuse to put a 750 DP on the car... maybe this is it? The 3310 has the little black plastic baffle on the front bowl, are the whistle style ones better?

 

[66Satellite47]

If the carb is clean, check fuel filter, maybe junk in gas tank/plugged sock? Either style baffle will work fine, nothing to do with your issue, they prevent the slosh under accel/decel blowing out the vent tube.

 

[70bigblockdodge]

If it has been together for a long time on a periodic use car the plate gasket in rear float bowl can shrink and leak, when you stop gas sloshes forward and drips out boosters in secondaries. Park faced downhill pretty steep and with idling or engine off you can see fuel dripping from boosters in secondaries that may be problem. Worth a look.

 

[71_Duster]

Carb is clean and fuel filter was changed last fall.

Its a periodic use car and the carbs been together a few years. I'll try the downhill trick and have a look.

I thought about the fuel sock but if it was the issue I would think it should present at WOT not coasting and even idling?

 

[RJRENTON]

If it has been together for a long time on a periodic use car the plate gasket in rear float bowl can shrink and leak, when you stop gas sloshes forward and drips out boosters in secondaries. Park faced downhill pretty steep and with idling or engine off you can see fuel dripping from boosters in secondaries that may be problem. Worth a look.

The OP said he was using s Holley 3310-S (?) Which I assume is one of the 750 CFM 4160 styles. If so, wouldn't there be a fuel balance tube between the primary and secondary fuel bowls? The origional 3310 and the -1 variant were 4150 designs with secondary metering a block. In addition, are the primary and secondary fuel bowls using side hung floats vs end hung fuel bowls as the end hung pontoon floats are usually a closed cell foam type vs brass. The closed cell floats are more boyant and reduce the tendency to leak and flood when having to panic stop or pointing down in a severe down hill stop. You can try and LOWER the secondary fuel level SLIGHTLY to reduce the possibility of fuel drip from the secondary booster venturi.
As a side bar, what part of Western Pa are you from? I use to live in Monroeville and attended many local cruises. Drop me a PM if you want to discuss. BTW...Look at my photo garage for my ride.
BOB RENTON

 

[66Satellite47]

It seems like a problem with varying float level, needle/seat or float? I presume OP meant 3310-5? Thought all 3310's were dual feed(no balance tube), but not sure. I did have a foam style float carb that had the variable fuel level issue, never figured out why.

 

[70bigblockdodge]

If it has a metering block my thoughts are no good. I'm talking about the ones with a plate in the rear, center hung plastic float (brass hits plate). The float bowl gasket also seals the plate to main body open area around the plate dries out, gets hard and cracks possibly allowing a leak past plate to feed holes to booster.

 

[RJRENTON]

If it has a metering block my thoughts are no good. I'm talking about the ones with a plate in the rear, center hung plastic float (brass hits plate). The float bowl gasket also seals the plate to main body open area around the plate dries out, gets hard and cracks possibly allowing a leak past plate to feed holes to booster.

I'm aware of the fifferences as the 6 barrel on my RS23V0A GTX's front snd back Holley 2300's (4160 style with metering plates) have never experienced booster nozzle drip due to gasket shrinkage. I run the fuel level SLIGHTLY below the sight plug hole (~ 1/8" low), which would tend to eliminate that issue. Although I've changed to the replacement metering plates with the Promax equipment as I've stagger jetted the end carbs to equalize fuel distribution issues which are fixable by drilling (what a PITA) the fixed orifices on the metering plates. You cannot see the Promax plates so "origional appearance" is maintained. Stagger jetting the main fuel feed orifices helps with the off idle transition circuit when the end carbs start to open. The fuel inlet needle is also increased to 0.110" to start refilling the float bowl sooner. This was just my solution....
BOB RENTON

 

[70bigblockdodge]

) have never experienced booster nozzle drip due to gasket shrinkage

Yours face forward, fuel moving away from plate on decel. If this is even the problem. My Challenger would have a occasional drip, I could not find out why (floats set right to even low to stop. Mine never made it stall. Problem has been non existent since last rebuild of carburetor.

 

[71_Duster]

Well I solved the issue and was going completely the wrong direction.

I kept looking at the carb because the problem became WORSE after I played with the float levels. However...

It died twice on me today, the last time was perfect as I was able to coast into the driveway and grab some tools. Carb looked ok, had fuel no raw fuel smell either.

Grab my starter trigger button and pull a plug wire... NO SPARK

Pull the rev-n-nator box out, toss the old mopar performance orange box in and I have spark, fires up and runs. Go for a test drive and no more stalling at idle. I noticed the temp on the engine would have to be up to 170-180 range and again only idling when the car would die and the problem was getting worse. I have to assume something is overheating in the box.

It has 3 years warranty but I bought it in 2014 plus they have no stock so back to Mopar orange I guess.