Is there a hose or something that goes to the hot choke inlet was looking at diagram and my choke will only close half way or so when i move throttle a little about quarter way back then goes back to no choke when i step on gas.

 

Is this an electric choke carb? Sounds like you're referring to the vacuum secondary.. if so, yes there should be a hose because if you're leaking vacuum and your crank case is ventilating improperly your choke will not work right, especially in the cold. If you could post a couple pics this would help alot.

 

Sounds like he's referring to a pre-3rd-gen hot air thermostat choke.

Also sounds like it's adjusted so it will open with the least amount of heat.

Yes, there is a hard tube from a plate with a tube going into the exhaust crossover passage that sucks a little bit of air through it to heat up the choke thermostat. No 3rd gens had it, and to use it requires an intake manifold that 3rd gens didn't have stock.



It's fairly simple to convert a hot air choke carb to electric thermostat - put an electric thermostat in it, hook the choke heater wire to it, remove the hot air hard lines, and plug the hot air port on the thermostat housing and air horn.

 

yeah my dad had a extra carb so i put it on there because it had a newer q jet on it but secondary valves opended to early and wasted to much gas for in town driving lol. It had a electric choke so i have the plugin with the little grey clip would it be easier to switch to electric or should i fix the thermostat choke o yeah i have a edelbrock torker 2 intake manifold on there too

 

I'm no expert on Rochesters, as I've said in many posts hahahaha, but I'm personally a big fan of electric chokes (my experience is with Edelbrock). I like just pushing the pedal once to choke it. Sounds like it would be easier just to plug in the hot wire and put a plug in the hot choke bung in the manifold. Are you putting your foot into the 4bbl too much to open it early?

Again, I'm no expert, sounds like five7 could better answer which would be easier...

 

WAY easier to convert to electric choke than to piece together all the little tubes and parts to make a hot-air style choke function properly.

Just need an electric choke element (which will fit right in place of the hot air unit) and remember you DON'T want the round gasket between the element and the choke housing- you need metal-on-metal contact to ground it and complete the electrical circuit.

You can plug the little vacuum port in the choke housing if you like when you convert it (no longer required to draw air into the choke housing), or you can leave it open. Makes very little difference either way in my experience.

Remember you still need to ADJUST IT once you have it installed. You can't go by the orientation of the electrical connector or the index marks (if your carb and element are even equipped with them). Once you change things around all that stock adjustment stuff goes out the window.

You want it to snap lightly closed when you first open the throtle on an overnight-cold engine and then it'll open fully over a period of several minutes with the engine running as it heats up (assuming the choke heater wire is supplying 12V power to it).

 

awesome thanks for the help guys i think i have a old qjet i can take the electric choke out of so i think im good to go!

 

so i ws lookiong it up and my carb is a rochester q jet m4mc serial is 17058229 is a weird setup up dont think i will be able to hook up a electtric choke to it what do you guys think?

 

If the metal part of the choke housing on the carb, the electric choke element will bolt into it.

Dumb question: I assume your original q-jet was of the computer controlled variety (aka, E4ME). When you changed to the M4MC, did you change the distributor?

 

yeah swapped my distributor out from my dads big bloc 402 is a delco remy i believe it said on cap not sure is that oem

 

Yeah, that's OEM. Off a 402 big block..... is that a points-style distributor? If so, you might consider upgrading at least to an HEI distributor. You can pick up a cheap HEI from Summit or eBay for not a lot of money.

 

Iirc an m4mc is a canadian emissions q jet. Which has a hot air choke