There is a 'shroud' on the exhaust pipe below the carb that the steel tube connects to for the stove. This is Texas....gotta have AC: yes kicker is used. It activates when the compressor is enabled. Glad to be of some help. Don't be shy, I'll help if I can.

 

So I was out checking vacuum routing, and I replaced a short section that goes to the Vac advance on the dizzy. When I pushed it back onto the dizzy, it spun around about a quarter of turn lol. Seems that someone was adjusting the timing and never tightened the bolt back down. I also checked the PVC which looked really clean from the top.....the guts had removed. So today I will be readjusting the timing and poping in a new PCV. I still don't see anywhere that the stove-pipe connection goes to by the exhaust, did all 300s in this year come with it?

 

I still don't see anywhere that the stove-pipe connection goes to by the exhaust, did all 300s in this year come with it?

It's raining cats/dogs here so maybe when it stops I'll try and get a pic of the thing. From memory: a flat-plate piece is held on by two nuts. If you can feel down the pipe and come across two studs that would be where the plate attaches....for all the help that is. Whether or not all 6s came with that? Guess so.....

 

I see that you need a vacuum hose running from the top of the air breather to the manifold tree located under the carburetor. It's the silver bar with the vacuum hose fittings on it. Looking at it from the front of your truck, I have the aforementioned hose attached to the third fitting from the left. The middle one is blocked off. Remove the vacuum hose off your dist vacuum advance and set your timing to 6 degrees BTDC (factory specs). Reattach the vacuum advance hose. NOTE: those thin plastic vacuum lines are very brittle. If one breaks, just replace it with a rubber hose. I replaced all mine.
Did not see anything more mentioned about your curb idle problem. Sounds like the choke is working well. You might want to back the fast idle screw down to about 1600 R
Pms (I think) when cold. Looking at that carb from the driver's side, you'll see two screws that are side by side. The screw on the right is your fast idle screw. The screw on the left is the curb idle screw. I think your curb idle screw is set way too low/backed out too far. I think the setting for that is 650 RPMs. Hopefully you still have the sticker under the hood. That should give you specific information. Good luck.

 

Ok, i'll be sure to supply vacuum to the top of the air cleaner. I had to go and get another bolt for the dizzy retainer, as the one that was in there was no good. I set the timing and she runs pretty good now. When you first start her up, the idle can be a bit irratic, but if you pump the pedal once she calms right down. I'm thinking that the inital idling issue is probably a choke problem. The choke is currently wired into a green wire coming off of the spark controller box. I read somewhere around here that it is supposed to be connected to the stator wire from the alternator. Unfortunatly, after a pretty successful test-drive she started spewing gas from out of the bottom of the carb so a rebuild is in order. I have never rebuilt a carb from a car before, but im going to get the kit tommorrow and carefully tear it down. I've heard that this is one of the easiest carbs to rebuild, so it should be a good learning experience for me.

 

Can someone tell me what the device shown on the left of this picture is for? It is not the AC kicker, as that is mounted towards the rear. It only pushes in, so im thinking it most be a push button normaly open switch (PBNO). It looks like the choke rod goes through the carb and smacks this thing in order to send a signal somewhere, but I have no clue where.

Also can someone verify for me that cloth-covered,white/black (stator) wire coming from the alternator is what is supposed to feed the electric choke?

 

The thing on the front of the carb looks like an "idle stop solenoid". The solenoid on the back of the carb is a dashpot/AC solenoid combo. The dashpot prevents stalling when decelerating to a stop. Like coming to a red light, or a sudden stop. the solenoid part should come on when you turn the AC on. It increases the idle a little bit.

 

So what exactly does the "idle stop solonoid" do? Is it to keep the engine from dieseling when you kill it? Any ideawhere it should beconnected?

 

I'm not sure why you have both the idle stop solenoid and the dashpot/AC solenoid. I had an '83 F100 with the I6, and it had just the dashpot/solenoid. When you turn on the AC, does the idle increase? The only thing I can think of is that the AC solenoid stopped working, and the idle stop solenoid was installed to handle things when the AC is turned on. On my truck, the solenoid does not work. But, I need the dashpot, so I left everything alone. If you do remove the idle stop solenoid, do not throw it away. those things are hard to get.

 

yeah it must be an electrical dash-pot or a throttle position solenoid. Pic #4 on my photos has a view of the mounting plate. The nut showing is attaching the mechanical dash-pot behind the plate. It's a spring-loaded 'bumper' for the throttle plate. The power to the choke must be an 'always Hot' circuit. If the choke heat-tube and the choke is working correctly, it is supposed to 'back off' the RPM as it heats up. The tube connects to a port in the exh manifold....if it's missing there are tube kits to fix the problem. Me, I disconnected all that mess, wired the choke Open and when it's Winter, give it a shot or two of 'pedal' and control the rpm with my foot. The engine warms up pretty fast even in the coldest temps. The circuit from the alternator is in the same harness from the alternator.....covered with a heat cloth wrap. Also: I've put the shroud photo in the album.

 

Hmmm it looks like hat stove pipe just picks up warn air from the area around the exhuast manifold behind the shroud. Thats basicaly what the warm air inlet on the intake does right? Is that the kicker mounted on the front of your carb? Mine has that plus one mounted above it on the passanger side but facing the accelerator linkage, plus the electric choke. Whats your opinion of the warn air inlet on the intake....any good?

 

The vacuum operated valve on the air-cleaner nozzle slams shut when at vacuum and brings heated air from the exhaust system to the incoming air for the carb. The vacuum controller on the air-cleaner is supposed to eventually cut off the vacuum in the hose which lets the valve open and mix the exhaust heated air with the cold incoming air. It's called the Thermac system. I hook the vacuum hose to the valve in the Winter, but only then. I believe it works pretty well. The only description that my manuals show that 'might' be that piece on the cab-side of the carb is a throttle position sensor. I see no electrical dash-pot in the manuals. Calif emissions had a tps. That carb on yours might be a newer piece than '81. Yes the kicker on mine on the radiator side of the unit is the part that adds a 100 or so RPM when the AC compressor is engaged. As far as the shroud hot-air to the carb...whether it is there or not wouldn't be a critical issue to me. Cold air makes more power than warmed air, but warmed air is good when it's cold outside and the engine isn't up to NOT.

 

Well I got the carb rebuilt, now im just waiting for it to stop raining so I can reinstall it. I took some pictures while I had it apart, here are the two devices attatched. The one on the right is mounted to the front, and the one on the left to the rear. Can someone identify which one increases the idle for ac? they both "kick" when I give them juice. The one on the left hits the throttle linkage (would be my choice) and the one on the right hits the vent arm thing.

 

3rd time is the charm. RIGHT is the AC throttle kicker.

 

Well the carb rebuild seems to have been a success. I have her running pretty good, and I don't have gas pouring out all over the exhuast anymore. Anyway the only question I really have is conserning the idle/fast idle, and choke setting. I can manualy put it over to the high idle setting, but it doesn't go there on its own when i start it. Is the choke supposed to pull it up to the fast idle before you start it or what? I have everything back exacty the way it was before the rebuild.