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Topic Review (Newest First)
06-25-2013 10:24 AM
66GMC Yeah, 30 seconds run time wouldn't generate enough heat to do that, and I think those that suspect the floats are probably right.

I'm not sure if you've ever confirmed the List Number of your carb or not.
I had presumed List #80551 earlier, which would have used a nitophyl side-hung float ... Holley #216-43.

I don't see a brass float option listed for those internally adjusted needle & seats ... but you could call or e-mail Holley Tech and ask them.
06-24-2013 08:21 AM
jtomasik Engine ran great, but when I shut it down, I couldn't get it re-started. I have two new batteries on the boat, the electrical system is simple and visible, I checked voltage drops, and everything was great. I took the starter in to the local parts dealer. The first place was a flop....they had some lady working there that couldn't tell my why the armature tested bad...she said, 'I don't know, it's an electrical thing'.... The second place let me watch the test, and I could see the shaft bearing was completely shot. Replaced the starter ($52), tested the crap out of the engine, and it fires perfectly every time, hot or cold. Still going to check out that fuel dribbling issue, but also going to concentrate on getting this thing ready to sell. Time for another boat! The full repair to make this engine run fantastic is about $150 out of pocket. Whew, thankfully I didn't panic and buy a carb!
06-21-2013 03:52 PM
jtomasik Awesome info. The floats were re-used. I'll probably pop the float bowls off next week and check. Thanks!!!
06-21-2013 02:48 PM
PatM Check out what Northern Chevy says.

Years ago I had problems with a car, removed and rebuilt the carb. Ran perfect for a short time and then the problem reappeared. I went through this 3 times. Finally, on rebuild kit number 4, I dropped the float (not included in the kit) into a cup of fuel. It sank to the bottom. I refer to this to this day as "the carburetor float that didn't".

Best of luck.

PatM
06-21-2013 01:31 PM
Northern Chevy Hmmm, so only ran for half a minute from a stone cold engine and its dribbling like that. That makes me lean towards a thought of too high a float bowl fuel level and were these floats changed out with new ones or were they reused. Some floats are bad for fuel saturating in a few years time and they will sink deeper into the fuel as a result so even if the level was set mechanically ok, because the float is sinking its the end result that matters. Did you say that this carb doesn't have level check plugs on the side of the bowl ?.
06-21-2013 12:49 PM
jtomasik 66GMC, good thought. However, it'll do it even after I've only ran the engine for about 30 seconds, so I'm doubting the heat could build up that quick to make a difference. Am I wrong?
06-21-2013 12:17 PM
66GMC I think I mentioned this earlier ..
Holley Heat Shield.


It keeps the heat away from the float bowls, and prevents the thermal expansion of the fuel in them.
06-21-2013 09:21 AM
Hogg Not sure if the Holley has similar parts or comparable parts that a Quadrajet has, but I also experienced rough running/popping when the secondaries kicked in, but on a Q-Jet.

After many hours of diagnostics we took the carb apart, there is a cam which lifts the secondary rods up out of the seats, and this plastic cam was broken. A 5 second replacement and the problem was instantly fixed.

peace
Hog
06-21-2013 08:34 AM
jtomasik I think this has been a sequence of clearing up issues. From the replacement of the coil until possibly simply burning some 'bad' fuel, as well as maybe incidentally fixing an air leak, it all worked out.

Anyone have an idea about the fuel dribbling into the carb from the primary jets after I shut the engine off? It's enough to cause too much fuel to be in the engine for the next start up....so it takes awhile to crank that out and get a good mixture.

*************
06-20-2013 10:34 PM
reevislong if its popping through the intake upon hitting the secondaries that mens the secondary circuit is lean try lightening the secondary spring see if it gets worse or better may need also a bigger metering plate in the rear may possibly need a bigger carb. check with a timing light to see if distributor is advancing how much and may be to slow.
06-20-2013 10:01 PM
Northern Chevy Its possible you had an air leak at the fuel pump inlet line or any other section of the line you touched a connection on as I rather doubt a bad fuel pump would suddenly decide to work properly. Then again some foreign matter in the float bowl that had come dislodged with all the hauling back and forth you did ... hard to say.
06-20-2013 09:21 PM
jtomasik Well, it runs great. Go figure. 'Stomped' on it a ton of times, and she pulls clean until she can't pull anymore. Rev it in neutral, and it's clean too. Go figure. Still have the dripping problem from the primaries after shutting it off, but at least we can go wake surfing now.
06-20-2013 05:57 AM
jtomasik Thanks for the reply, guys. I'm curious why the valve 'float' or points 'float' would move. That is, when I first started experiencing this problem, it'd hit in the 4000 rpm range consistently, and it would happen ONLY when the secondaries would open. Then, as I tweaked things, that 'float' effect moved into the 5000 rpm range, and last night it's around 6000rpm. It still shows up when the secondaries open, but not immediately anymore. Last night, the secondaries would open about a quarter of the way without the issue, but as I pushed the throttle open more, the issue started.

Not sure if I put a wrong gasket in. I got one of those generic holley rebuild kits. I followed the diagrams and directions closely. And, I took pics of each step when I disassembled the carb, replacing the old gaskets with gaskets that seemed the same as the old stuff.


I'll take it to the lake tonight.
06-19-2013 09:39 PM
Northern Chevy I agree with 66GMC's line of thinking, you might be butting up against a points float issue and/or valve float. Do you know what the rated maximum RPM of this engine setup is ?

When you reinstalled the carb, did you make sure to not eliminate a thick gasket or a resin style spacer with two gaskets as it sounds like your carb is getting a certain amount of heat transfer when its shut down and the fuel is expanding/boiling and it wants to find any path it can out of that space. If its bad enough it can flood the engine when you go to restart.

Unfortunately testing it with no load won't tell much in the fuel rate used vs whats being supplied as it takes a fraction of the fuel to rev it out .... its like sitting in your driveway with a pickup that has an almost totally plugged fuel filter, sure it will rev out there, but fall flat on its face when driving it.
06-19-2013 09:12 PM
66GMC At 6,000 RPM ... that would likely be valve float that you're experiencing. The fuel that you see running over when shut down is likely due to thermal expansion of fuel in the bowl, as the fuel pump is no longer pumping, right?
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