Choke Thermostat (Choke Unloader) - Not working

87 B2200, orig. carb.

After fooling with the choke unloader (black round thing on back of carb. that is elect. powered to open choke) quite a bit, I think mine may be bad. When its very cold outside it appears to do nothing (choke stays half closed and stuck in high idle). After the engine warms up and I move the choke linkages around it seems to start working again. I have checked the voltage and ground on the unloader so I'm leaning toward it as intermittently bad when cold.

Anyway, can anyone tell me where I can get a new Electric Choke Unloader (choke thermostat) for this here truck? (carb part source)

Also, any other advice on this problem would be welcome!

Welcome Phils2200, I just did a search and came up blank but you may want to call National Carburetors in Jacksonville, FL or Carbs Unlimited in Washington state and ask them if they could sell you a choke heater for the Nikki carb that is on your B2200........it's worth a shot. I have bought carbs from National Carbs before and everything looks new on it so I'm sure they have a source for these.

Hey, thanks Axel!

I'll give those places a try.

Follow up: OK! for those needing the Choke Thermostat or Choke Coil (as it is commonly called) I called National Carburetors as suggested above and they do have 'em. The guy quoted me $25 plus $5 to ship. That's a heck of a deal if you need one.

But, I still wasn't quite convinced mine was bad, so this morning (nice and cold out in the garage) I went out to have another look. I took the C.T. (choke therm.) off one more time to check the electrical connections in this fricker.

1) I disconnected the power lead from the alternator (it powers this thing)

2) Meas. the resistance (continuity check) from the power term. to inside
the CT housing. 1.5 M ohms (1.5 mil ohms). Virtual open circuit. AHA!
The culprit is revealed! This is why the choke was not opening on cold days.

3) At this point I didn't know if this part was available, so I attempted to fix it.
There is a rivet that joins the outside connector to the inside piece of metal
that goes to the heating coil. I set the C.T. up on the valve cover with a hex wrench underneath said rivet and gave it a rap with hammer and punch from
the other side. Measured again. Near 0 ohms. FIXED!

Started her up and choke slowly opened (and carb came off Hi-idle) after a couple minutes of running. Hallelujah!

Hope this helps anyone else with this type of problem.

Additional troubleshooting info:

Measured about 2.6 ohms (the heater element) from power connection on outside of C.T. housing to ground plate also on outside of housing (after fixed). I assume this is normal for a good one. (This was with power wire unplugged from Alternator).

Good Luck with Yours