thermoquad help

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The 2ndary jets and metering rods are correct. And the pri jets may be if the #'s are 4099. So something is leaning out both the primaries and 2ndaries.

If the car drives poorly on the primary circuit(cruising)and when going wot, look for the things that can cause a lean situation. If you remove the carb, be sure:
1)the carb base gasket opening/center 'matches' the primary bores in the base; you do not want the gasket to be smaller than the primary bores in the base of the carb.
2)set the carb back on the intake without the base gasket and see if the carb fits flat on the intake mounting flange with no attaching bolts.

Also check any vacuum solenoids on the carb do not have vacuum leaks and the same with the vacuum advance on the distributor if it is in use. The correct port for distributor vacuum advance is the driver side front port in the base of the carb.
 
i dont really think there is a problem in the secondaries. yet. its a fresh clutch so im not trying to go nuts with full throttle blasts. all i have really done is toy with the rod hieght, drill the squirter, and tighten the air door. the rod hieght and tightening the door pretty much eliminated the popping at cruise speed. it sounded like a damn popcorn maker under the hood with the tape over those holes. im taking it they are air bleeds and the tape didnt let enough fuel flow? im searching and came up with no useful info, but had some ideas, should i drill the 3rd hole in the acc pump linkage, or possibly change the hieght of the acc pump rod? it pumps a lot of fuel, i cant say for sure the plunger is in perfect shape but it definitely blasts out fuel. i dont know jack about these carbs. never messed with one but to me it seems like the problem is coming off the acc pump shot making the transition. if you hold it at that spot it will want to stall. i dont have a tach yet so i cant say what rpm its happening at, but its right off idle, i think you could crank up the idle speed screw and position it at that dead spot.
heres the crazy part, i have a fast ez efi in the box, id really like to get this carb to work out if i can figure it out i might not even use the efi. im not expecting efi like results but this isnt a crazy big cam big compression mill, it should work decent.
 
The secondaries could be opening up just a tad ...and messing up this whole deal at low speed. Just wire the air-door CLOSED so there is no action there. What rear end gear ratio do you have? .. a short gear(3.2 or 2.9 or so) requires special tuning.
 
My present combo is a lite-weight B-body with a decent 440 ... 2.76 gear with about a 26" tire .... and I have had to delay the secondary opening BIG TIME....or it will bog.

Your gear should not be a prob.
 
i tightened up the air dor some more. the acc pump wasnt moving all of the time with the throttle. took me a few times rebending the linkage and setting the pump hieght to get it to where it would squirt any time you moved the throttle at any position. my drilled out squirter seemed like too much so i soldered it and drilled it to 031 its pretty good now. i drove it maybe 35 miles yesterday just cruising. pulled a plug today and they are still white like brand new. i can feel a light surge when holding a steady cruise speed. and when driving normal a very quiet pop when i let off and shift. im not messing around with full throttle blasts, i have a brand new clutch im just trying to get it ready for a road trip with the family. so im thinking i need some jets. oh i noticed i had the pcv hooked up to a wrong port on the carb it wasnt getting vac so i hooked it up to the manifold. forgot all about it and went to go for a ride it was leaning out big time again. i switched the hose around and it was ok. how close or far should you deviate from the 1 turn on the rod hieght adjustment? i guess the closer the jet is, the closer you will be to the 1 turn?
 
oh i checked for vac leaks when i first started having issues. i didnt notice any.
 
the accelerator pump pop is gone. i had it to where it would cruise ok, but the plugs where white like out of the box and i was getting a small lean pop every time i shifted. i drilled out the primary jets to #38 drill then went to #37. while i had it apart i cleaned it and blew everything out. now there are severe drivability issues. now the mixture screws have no effect. the vaccum is a little bit lower but there doesnt seem to be a leak. you cover the top of the carb and it will die. when taking off and the rpm start to pick up it just surges. it doesnt have a whole lot of power and now it doesnt want to start unless you hold the throttle open. i had set the float but i used the wrong setting of 19/32 that fouled out all of my plugs. i went back and set them to 1" new plugs, it still doesnt want to start. they were about .965 before i touched it. the only time it clears up is when the secondaries open. i think im about to throw in the towel and join the club of people that call them thermobogs. i was really hoping this carb was going to work out, at least for my road trip to florida for the power tour. now it looks like its going to keep me from taking the car. i spent a week trying to figure this thing out and didnt really get anywhere. im stumped.
 
No effect of the tuning screws is way to righ or lean. Considering the plugs still look brand new, I think yur way to lean along with the other clue of surge and pop. The other thing is, "It clears up when the scondaries are opening" is another sign of lean.

These things (TQ's) do take a leaning curve. Once you have takin the time to dial it in, you'll be fine.

I run my TQ lean on my 400. Once it warms up, it is very crisp. But it needs to warm up. The hot air takes up more space than cold air. Less air (When warm) has the carb running a ever so slight tad richer.
 
the plugs dont look new anymore. i did 3 things yesterday and it went from bad to awful. i drilled the jets 1 size, then i went one more size. when i drilled it one more size i decided to check the float hieght.
i set it to 1" from the gasket with the lid up side down.
i also sprayed the passages with carb cleaner and blew it all out.
now the plugs look wet and are darker now. not black but dark. it doesnt want to start, and it drives like crap. sure seems like a bad needle and seat or float. i dont see how when they were fine. i guess i somehow damaged either in the process. i think the surgine can be it flooding. its no longer popping.
 
I had a bad needle and seat in mine and they looked fine. I found you can test them by turning the top over with the floats in place and blowing into the fuel inlet. If you can move air, you have a bad needle and seat.

Mine didn't make it bad to drive, but it made a mess of the carb with the fuel that was weaping over the top. Don't know what the problem is on your carb, sorry.

You can weigh the plastic floats to see of they are good, the brass ones you can put in some hot water and watch for bubbles. Don't remember what the weight is for the plastic ones, though.
 
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