I like my ThermoQuads because I enjoy punishment

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Bill Crowell

Bill Crowell

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What do you guys recommend about the TQ where if you don't drive the vehicle for about a day all the fuel in the bowl evaporates and then you have to crank forever to get it to start? That's really hard on the battery and starter. (I'm using stock mechanical fuel pumps, and hoping I won't have to install electric pumps and regulators on 2 or 3 vehicles with this problem.) It starts immediately and keeps running if you squirt some ether into it.

Is this likely a problem inside the TQ, or due to insufficient fuel pressure going to the TQ?

Thanks very much for your advice.
 
I have had this happen on an old Monaco. The first three tips below are common issues. The fourth tip is what the problem was on my Monaco.
1. Check your float level, make sure it's not way low causing less fuel to be stored in the carb.
2. It's possible the fuel is leaking internally in the carb. Might want to refresh the carb gaskets.
3. Blocking off the exhaust crossover in the intake will lower the temps the carb sees and might slow down evaporation.
4. My fuel pump was bad, allowing the carb to drain back into the pump. After rebuilding the carb and setting my float levels twice with no improvement, I talked to an old retired Chrysler mechanic. On his advice, I replaced the fuel pump, and the problem never happened again.

Todays ethanol based fuels do evaporate much more quickly than the gas we had when the TQ was designed. If your problem does turn out to be evaporation related, I would install an electric fuel pump so you don't have to crank the motor on the starter to fill the carb bowl.
 
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All my carb equipped vehicles do that now, regardless the carb type. I guess it’s the gas you buy now. Let it sit for a few days and the bowls are empty, especially if the engine was fully warmed up when you shut it off. Choke, pump, crank and crank. Fine the rest of the day, usually good the next day too.
 
I think those plastic fuel bowls on the TQs are prone to cracking in the bottom and then they leak down into the intake. I've seen some write-ups on that issue and the fix seems to be JB weld or similar, I believe???
 
Inline electric fuel pump. Flip switch to turn it on, let it cycle for about 30 seconds pump the gas and turn the key.
 
Like others have said, sounds like fuel boil to me. Use the thick carb spacer gasket and insulate your fuel lines. And if possible use non ethanol gas. Ethanol gas boils at a lot lower temp.
 
moparmat2000 said:
Inline electric fuel pump. Flip switch to turn it on, let it cycle for about 30 seconds pump the gas and turn the key.
Click to expand...

I have run Electric fuel pumps on everything since the 70's. Fires up before one revolution. No fuel leak from the mechanical pump to the oil pan.
 
moparmat2000 said:
Inline electric fuel pump. Flip switch to turn it on, let it cycle for about 30 seconds pump the gas and turn the key.
Click to expand...
Can anyone post a write up of how to install an INLINE electric fuel pump setup..as easy as possible for dummies like me..lol? I too have the same issue with cranking forever to fill the bowl before it will start..
 
Block the heat crossover in the cylinder head. Or better yet, get a Strip Dominator, and do some work on the plenum to make damn sure the secondary throttle blades don't hit the plenum and run it.

All that heat in the intake was never a good idea. Been blocking it off, or using intakes without a crossover since 1980.
 
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