Carb choke question

[willy3486]

I am back working on my Father in laws 1970 C10 with a 307 that my wife and I bought from her brother. For the last couple of years we were taking care of her mother and then dealing with her estate. Now I am getting back to the truck. I can do some engine work, replacing parts,etc but I leave stuff like engine rebuilds to the experts.

With that said I had hired a fellow down the road to do some work on it like carb rebuild,brakes,etc. He has since moved away and at the time for some reason he couldn't get the parts needed locally for the carb. Due to dealing with the mother in law and his moving we never got to work on it again. He said that a part with the choke needed replacing. I am wondering if anyone knows where I can get these parts or if I can get them locally, I have a advance and orieleys. I am thinking the from the photo below I need the part on the left may be what he said, Is this the same part?

http://www.ebay.com/itm/BWD-VC307-Ca...CBexMg&vxp=mtr

Also I am wondering if this next part is the item going down to the manifold. Is this part mounted on the manifold or does this carb only use the one part linked above?
http://www.ebay.com/itm/1969-1970-Ch...xX8VpX&vxp=mtr

Now it will not start on its own good but if you move the choke on the carb manually it starts. With that said does anyone know what these two pieces are called so I can ask for them? Should I be able to get them at orieleys or advance? I don't mind replacing the parts if I can find them. IIRC the truck is all original except for any replacement parts he put on. Does from the photo below look like the part or parts would fix it?

[B. W.]

the choke has bailing wire rapped around it right now (I'm sure you know this) the choke diaphragm is probably bad & will need replaced. The thermostatic coil (part on the manifold) may be OK. You should be able to see the choke rod move as the engine warms up. The rod is attached to the thermostatic coil on one end & the choke plate linkage on the top. If the rod is moving enough to open the choke when the engine is warm, the thermostatic coil is OK, if not, replace the coil.

With the air cleaner off you can see the closed choke plate (engine off, engine cold) with the engine running but still cold the choke plate should be slightly open (there is a setting for this, use a drill bit as as gauge to measure) that's what the vacuum diaphragm does - hold the choke plate slightly open, so the engine gets enough air it does't stall. When you WOT the choke plate should open

[willy3486]

Thanks B.W. . I read your post a couple of times and your post helped me to understand its operations. I also remembered the fellow describe the issue similar to what you posted. IIRC he said the choke diaphram was bad, Like you said. I will print out this picture I posted and ask for it. I will see if the local place can get me one or at least order it. Thanks again.

[geezer#99]

Before you go that far, hook up a vacuum hose to it and pull a little vacuum on it with your lungs. Should be easy to move.
Take the wire off it first though.

[Wrenchbender Ret]

That part is known as a Choke Pulloff. A parts man should know what it is & order it for you. It may not be available any more.
The replacement may be plastic.

[willy3486]

Originally Posted by geezer#99

Before you go that far, hook up a vacuum hose to it and pull a little vacuum on it with your lungs. Should be easy to move.
Take the wire off it first though.

I went out and tried that. I tried to put a vacuum on it and even blow into the hose. It acted like there was nothing on the end of the hose and no pressure on it. So it looks that the diaphram in it is bad and lets air leak out. I will order a choke pulloff as suggested. Thanks folks.

[willy3486]

I have it on order now and should get it in a few days. I will probably install it on Friday. I have one question though on it. I have one last question though. As far as adjusting it does anyone know the size of the drill bit used to adjust it? I see how to put it on and adjust but I don't know the right size of drill bit.

[geezer#99]

Uh!!
Nothing to adjust.
Remove and replace!

[willy3486]

Originally Posted by geezer#99

Uh!!
Nothing to adjust.
Remove and replace!

OK, I must have misunderstood what was posed preveous about the drill bit. I will put on and see how it does.

[geezer#99]

I guess I should sit a little closer to the 'puter! LOL!!
.
BW suggests a drill bit as a gauge for how far the choke plate should be open.
All you need is to start it cold and see how far the choke pull off opens the choke plate. Should be about 1/4 inch. If you need more or less, then you might need to bend the connector link from the vac pot to the choke arm.
Hope that's clear as mud!
Just put a new pot on and it should be good.

[willy3486]

Originally Posted by geezer#99

I guess I should sit a little closer to the 'puter! LOL!!
.
BW suggests a drill bit as a gauge for how far the choke plate should be open.
All you need is to start it cold and see how far the choke pull off opens the choke plate. Should be about 1/4 inch. If you need more or less, then you might need to bend the connector link from the vac pot to the choke arm.
Hope that's clear as mud!
Just put a new pot on and it should be good.

Thanks again. On vehicles I can do bodywork, some mechanic stuff like brakes,changing out parts, I can rewire one but when it comes to the carb and teardown of a engine I am lost. I will put it on and then come back to this post for help.

[willy3486]

Update on the carb. I got the part but it did not have the bracket on it. So I cut the bracket off the old one and was able to trim it to where it would slide on. After it went on I started it up. I let it warm up and after a minute or so it ran fine. From what I can tell it runs fine after it warms up. Thanks again as it seems to run fine now.

[68speedalert]

Make sure that after it warms up, that the choke plate is vertical; straight up and down. If it isn't, you're not done. Sorry.

[willy3486]

Originally Posted by 68speedalert

Make sure that after it warms up, that the choke plate is vertical; straight up and down. If it isn't, you're not done. Sorry.

I got out in it yesterday. I started it and the choke seemed to work fine. After it was warmed up the choke plate was vertical. Only issue I really saw was after a while. I went up to a farm supply for some posts and came home. I unloaded them and hooked my small trailer to it. I cleaned up some on the land I bought that is next to my house and hauled stuff from that area. By the afternoon it would start fine but acted like the carb was off. It would idle but you had to really give it the gas to not kill the engine. It got to where it would die trying to take off. It may be due to not being run much in the last year or so. I plan to have the steering unit changed out due to a lot of play in it so I will have them check that as well. When I had it gone over after I got it they said the steering unit was adjusted all the way and needed to be replaced. So this issue looked to be resolved and the few issues it has don't seem too bad.