Choke Thermostat (Choke Unloader) - Not working
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Choke Thermostat (Choke Unloader) - Not working
phils2200
+1y
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!
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!
Post was last edited on Jan 07, 2013 09:19. Edited 2
times.
axel breaker earl
+1y
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.
phils2200
+1y
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
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