I've had so many questions.. thank you all for your help. The choke isn't working. I can get it to stick open or stick closed. Pumping before starting doesn't close it. If I poke it, i can get it to close but then it doesn't open.

1. Starting, which is right: A-Key on, pump it, start motor? Or B: pump gas, key on and start? (A seems to work better)
2. What's the general outline of steps for troubleshooting?
   1. Spray with carb cleaner, then some kind of lube? (what kind of lube?)
   2. .. then look at repairing it?
3. The black heater thing is rivited on, is it serviceable / repairable? Drill out the rivets?
4. Is conversion to manual choke a possibility?

 

You do not have a electric choke, you have a electric assist choke. It only works when it's about 60 degrees or higher around the engine. The main thing that makes the choke work is the hot air tube that goes down to the exhaust manifold. That is rusted off by now on most trucks.

You should go out and take the aircleaner off, and then loosen the 3 screws that lock the black piece. Then while holding the throttle wide open(engine off) rotate the black piece with your other hand. You should have full control of the choke door in the top of the carb. If you do, then I would check the hot air system going to the choke. If you do not have control over the choke when twisting the black piece, then you need to take the black piece completely off and make sure the fork inside is engaged properly in the choke arm linkage.

 

It looks like it's riveted on, but I'll check the other side.

 

Dave did you se the OP #3? No screws.
I think I have seen where others have drilled them off just don't drill all the way thru and make the hole bigger as you will need to use screws to hold the cap in place.

I would first before drilling is spray the carb & linkage with carb cleaner to see if that will get the choke to close.
I would have to check my 300 six to see but most have a weighted arm that helps close the choke check to see if that went over center and not pushing the choke closed.
If that all does not work they do make a man. choke kit but you will still need to drill the rivets to install the kit.

As for starting I have always pump the throttle 2 times before turning the key to on/start. Most of my other cars/trucks had electric chokes and I did not want to heat them up before I started the motor.
Dave ----

 

It is standard procedure to drill those rivets out when rebuilding the carb. You cannot properly rebuild it with those in place, and you can't adjust the choke with those in place. That carb is way overdue for a rebuild. I would get a kit for it, they should have self tapping screws in the kit to replace the rivets.

 

Is there any kind of lubricant I should spray it with after the carb cleaner? Or maybe that's a bad idea?

And, what is this electrically tunable carb called? (or are the rebuild kits fairly universal?) From rock auto, it might be a "YF" or a "YFA"?

 

Spray carb cleaner is almost ineffective, by the time the carb is gummed up, it's best to remove it, disassemble, dunk it in acetone or the like, then reassemble with a kit. If you go on Autozone, get one of their GP Sorenson kits, they're USA-made too; also, pull off the metal tag on your carb and cross the numbers on the AZ site.

 

None of the AZ kits seem to have anything to do with the choke (2nd pic). I'm kind of thinking of going "manual" -- seems cheap easy and sort fun. Would this kit work? link to az



manual choke kit






Rebuild kits

 

The carb kits will have the choke gasket(s) in there too; part of the reason your choke is sticking could be that the carb is gummed up. There's only 2 main parts to the electric choke: the coil/cap, and the metal heater line from the exhaust manifold, and the choke coil rarely breaks. If it does, you can head to the junkyard and likely pick up a few for cheap

 

I am a manual choke guy myself. I can appreciate a properly operating auto choke, but when they get some age on them, it takes some dedication to get them sorted out.

If you want your manual choke to work the best, carefully search out a area right behind the engine to go through the firewall, and have the most direct path with no bends in the cable. I used to always take the cables and leave them full length and run them through the rubber seal that is around the steering column, and then up under the dash. This creates a lot of bends in the cable and it's difficult to operate.

The very best one I ever did was on my 80 right before I sold it. I carefully found a spot to go through nearly lined up with the carb where the cable came off the engine. I then mounted the pull **** at an angle on the pass side of the steering column under the dash, pointed to the driver. This put one very slight 45 degree bend in the cable before it went through the firewall. Once it got it through the firewall, I cut most of the cable off. You can do this, and then unwind some of the metal spring around the cable. It worked really well this way.

 

I picked up a manual choke conversion kit and am currently trying to figure out how to drill the rivets out.