Can you get the choke perfect on a Thermoquad?

[WH23G3G]

Ok after the timing was retarded way too much and the carb caught on fire I've gotten my 73 400 back to running condition. I got the timing back to where it should be and the idle where it should be. I'm going to try and drive it around and get the motor warmed up tomorrow if it's ok weather. I have to see if the overheating issue was because of the timing, it wasn't off much before the carb was being tuned but that carb was in bad shape so I haven't been able to determine the exact cause of the overheating. It's not the thermostat now. I've got my laser thermometer handy this time to check temps.  So now that I've got a workable Thermoquad that's supposse to be rebuilt and the timing right I want to see if there's a way to adjust the choke better on this thing. It doesn't like the choke at all no matter what temp it is outside. What's causing the most problems with the choke? Is something not adjusted right? I know the heater switch is working and the linkage from the thermostat is free. The measurement from the top fo the choke control lever hole to the base of the carb is dead on what the carb specs call for. What else do I need to check? Did these have this much trouble with the chokes when they were new cars?

[71bee]

Nope. when these carbs were built, they were making a whole different batch of gasoline compared to what they use now. the choking issues will arise on a number of different carbs, these days especially. you more than likely will have to pump the crap out of that Thermo-quad if it sits for awhile without being started. my T-Q's run great when I can fit a #2 pencil between the air valve & the housing. the next step is to have your fast idle cam tuned just right. if it's set too lean, she'll sputter & gag. mess around with that monster flathead screw, until she purs like a kitten. if you are still having issues, adjust your air/fuel mixture screws 1/4- 1/2 turns at a time. just make sure you turn both screws the same amount.

[flyinlow]

"Can you get the TQ choke perfect?"

Short answer,no.

Like the Bee man said, gas blended for fuel injected engines sucks. Aluminum intakes with no heat, unheated air cleaners, headers, can make TQ's, or any carb cold blooded.

The engines originally had electric assit chokes and some had cold idle enrichment to help cold .drivabilaty.

On a stock set up you pumped the gas once to set the choke, which would be fully closed. Start the engine, the choke pull off would be activated by manifold vacuum,opening the choke plate to a certain drill size specified in the Service manual.Then as the intake warmed by exhaust gases flowing thru the heat cross over pasage ,the choke would fully open in 5-10 minutes. Many interelated adjustments detailed in the service manual. This assumes you have a stock intake,  ex. manifolds, and air cleaner.

I put a manual choke on mine, too many mods to make the orrigonal setup work.

If you are not using any choke to start on a cold day,you are either pumping the gas about ten times to start it and feathering the gas for a few minutes or your carb is way to rich if it runs well cold with no choke. 

[71bee]

It's not just the Thermo-quads. all carbs have a harder time starting with this crappy new fuel. the AVS on my Bee needs a ton of pumping to get going as well after sitting for awhile. the Holley's usually start easier because their 9 outta 10 times running rich to begin with.