Flooding (intermittent) 1895 Quadra Jet

I have a 1985 Chev Caprice Wagon with a Quadrajet (17085990) Non-computer/electric choke and have an intermittent flooding problem. The car will flood so bad that it will stall out with fuel dripping out from
the somehere near where the choke attaches. Following the stall it will require WOT to start. Other times it will run just fine, quite well in fact.
Just this afternoon I barely could keep the car running to get back to work. I parked the car (level) until I left for home about three hours later and the car started and ran just fine all the way home (about 30 minutes in city).
I had removed the carb, cleaned out bowl, installed new needle valve/seat, filter etc. but problem still persists.
I will take the carb off again this weekend but am not sure what I should be looking for but I suspect the needle valve is somehow at fault.
I have the original mechanical fuel pump but it was replaced about 50K miles ago.
Any advice would be appreciated.
TIA
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Whew! Kinda threw me off there for a minute. I didn't now that the 1895 Chevy had a Q-Jet LOL. One problem with the older Q-Jets was the plugs in the secondary wells. They would leak after the carb heated up and fuel would leak down into the manifold through a weep hole in the base. This problem usually caused it to flood after it sat for a short period of time. The fix for this was to drill out the plugs and replace them with O-ringed plugs - OR - install a rubber plug in the void that prevented the wells from leaking.
But, you said that it was leaking around the choke so this may not be your problem. Since you have replaced the needle and seat, did you re-check the float level? As I remembe it, the only passageways around the choke carried vacuum and heated air.
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I second the suggestion about the float level. Likely, it is set too high, is sinking (very possible with older soldered brass type, newer black closed-cell plastic less likely). Perhaps the needle is sticking; if the fuel filter has been allowed to clog, the incoming fuel pressure will push the filter back on the bypass spring (which *is* present, correct?) and unfiltered fuel will enter the carb. This situation could cause repititive needle sticking, particularly with an older vehicle, as quantities of detritus may have accumulated in the fuel tank over the years. A less likely possibility would be burrs or damage on the float arm or pivot pin, causing the float to bind and hold the needle up. Omission of the black plastic filler in the bowl can cause fuel sloshing during vehicle maneuvers, but I would guess it would require some seriously aggressive driving, coupled with a high float, to slosh enough fuel out the vents and into the venturii to flood the motor out. Leaving out the filler usually causes a lean out when slosh uncovers the jets.
Obviously, the choke assembly should be checked over to insure that the butterfly is opening fully as the engine reaches operating temperature. Some Q-Jets use a pull-over choke enrichment system (I do not know if your carb does or not) that can be identified by two small calibrated holes in the throat of the choke tower, just below the choke butterfly's closed rear edge. If the choke is not fully opening, these orifii may discharge fuel, greatly amplifying the over-rich condition of a malfunctioning choke.
A full cleaning/rebuild may not be a bad idea at this point, as once a seasoned air horn gasket is pulled up, it's pretty much trash.
On a somewhat related note, the carb number given does not compute; the second to last digit indicates the division, and '9' was used only on Q-Jets manufactured for Ford on the 428CJ engine. (FoMoCo/Holley couldn't build a carb that would pass smog reqs.) If you try to find that number on an adjustment specs table in a rebuild kit, it won't be there. The division number should be 0,1 or 2 for a Chev. Furthermore, a 1708 series passenger carb is an E4M, or computer-controlled carb--you are positive your carb does not have TPS and MCS connectors (non-ECM)?
Best luck, Mark
On Thu, 23 Oct 2003 19:05:07 -0600, Lloyd Cimprich wrote:

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Thanks all for the feedback, the Carb # is correct as stamped, in fact I have three of these cars all with identical carb and #. Two are 85 Caprice wagons and one is an 83 Caprice sedan and I have not been able to find a spare carb of same #. Can anyone suggest an equivalent?
The car ran perfect, smooth and even power, all day today!! I think I will install a clear in-line filter as I suspect something must be getting to the float needle. Just in case I will pull the carb and re-check all assembly etc..
Thanks all.

Q-Jets
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A nice Edelbrock Performer would wake it up a little, and it is competitively priced to a remanufactured Q-jet......at least in my sources..

will
the
build
out
it
well
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A Q-jet overhaul can be performed, even by a novice, on a Saturday at a cost of $30. An AFB (called performer when sold by Edel) will cost at least $250, plus rods/jets as necessary to dial it into the car, and require at least as much time to tune as the Q-Jet overhaul, which is obviously already calibrated to the engine.
Admittedly, I am not much of a fan of the E4M (computer) QuadraJets on non-stock engines, but even a 1705 series "emissions" mechanical QJet will, properly set up, beat the socks off an AFB any day of the week. The correct QJet, with a little tweaking, can support a 9 second drag car.
I am personally very interested in learning more about the three carbs on the Caprices; I am not insinuating that Mr. Cimprich's information about the stamped numbers is wrong, but I am rather intrigued that three carbs (including one of the incorrect year for the vehicle as per stamping) of similar application all appear to be improperly stamped. (assuming, of course, that they are the original carbs.)
On the subject of replacement carbs, any QJ from a similar displacement and power rating engine application can be made to work sufficiently here. The only catch is that an E4M (computer) carb must be used with an ECM and 7-pin HEI module; an M4M (non-computer) carb must be used with a 4-pin HEI module. In short, if there is a weatherpack connector attached to the distributor, use an E4M.
Cheers from a QJ fanatic, Mark
On Fri, 24 Oct 2003 19:26:56 -0600, Eightupman wrote:

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Yes....I agree the kit can be bought for about $30, and rebuilt yourself, but I was speaking of a factory remanufacture...not a bench rebuild. I also found a factory remanufactured Edelbrock for about $189 (consumer price). Ultimately he wants the car fixed. And truthfully I would spend the $30 first and try to rebuild it myself...but most would not want to be bothered. And it would be an excuse to spend a little extra mad money on a toy...

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I've rebuilt a few pre-emission Q-Jets and they really aren't that difficult. The secret of doing a home-rebuild is to get a good manual (in addition to the instructions that come with the kit) and take your time doing the job. The performance of the Q-jet depends on how well you set the carb up on the bench. I got my manual from Helms and while it wasn't a very lengthy manual, it covered the subject well. Just remember to keep all extraneous dirt out of the carb or you'll be wasting your time.
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will
the
build
out
it
well
Don't discount the float. The black plastic foam floats get gas logged. When they are cold they float. When hot they sink.
Al
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I was not able to obtain the correct float in time to install but I did install a filter in the rubber fuel line just before the pump. When I parked the car to install the filter it was running great but started to flood again when I restarted and had to pump throttle a couple dozen times to clear it up.
It ran just great until today when I moved the filter around to try and see what it trapped. Once again it flooded just after startup and took a little while to clear up.
I am beginning to think the rubber fuel line to pump is breaking up.
Now that I have the new float I remove carb, open it up, inspect and clean and install new float. I think I saw a suggestion that the needle should hang from the float in a particular way but do no remember which way.
Any additional thoughts from the group would be appreciated.
TIA

When
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From personal experience (car fire) I would strongly recommend avoiding glass or platic (transparent) fuel filters.
On Fri, 24 Oct 2003 16:34:50 -0600, Lloyd Cimprich wrote:

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