Fuel Problems?

[HEC1]

Hello everyone, I am new to the forum and also new to Dodge trucks. I have a 1949 B1B with the flathead 6. It has a Carter BB 1 barrel carb on it. I am really confused as to why it is hard to start when cold? I have a new Interstate 6v battery, I have new 00 Gauge battery cables, cleaned all ground points, checked compression an is good, all the electrical stuff seems fine. When I try to start it cold, I must give it a small shot of starting fluid and it starts really fast! If I don't use the starting fluid I can't seem to get it started! Once it is warmed up, starts fine. I thought maybe it was the gas, so I put 8 gallons of fresh gas, still did not help. Does anyone have advice on what to check or what it might be? Please let me know and thank you in advance!

[Plymouthy Adams]

depends on if you are properly using the right sequence when starting an engine with the Sissons choke and if the choke itself is connected and operating properly..it is not anywhere near an automatic choke and must be set by proper human intervention..proper depression of the throttle and letting it up during cranking is the only way to set the choke plate and lock the high idle

[Don Coatney]

You did not mention the time interval between cold starts. Good possibility the gasoline in carburetor float bowl may have evaporated. Have you tried using short 3-5 second intervals between starter attempts and pumping the accelerator pedal many times between and during starting attempts? That is what works for me. 

[Jeff Balazs]

Try this starting procedure on your truck. Pump the gas pedal one time. Pull out choke about 1/3 to 1/2 of the way. Pull out hand throttle the same amount. Turn on ignition and then step on the starter pedal. Should fire fairly quickly if all your settings are close.

Jeff

[HEC1]

Mr. Coatney the time between the cold starts is usually 8 to 12 hours. It does start fine after it is warmed up. Mr. Balazs I have done this procedure after I found it in the Tech section. The truck does start much better after I follow this, but it is still hard on the cold start. Mr. Adams I am not sure if I have all those cables on the truck, I only found a choke cable and that's it. I did watch the YouTube video on rebuilding the Carter BB, I think some of the linkage parts might be missing from my carb. It looks like it has been overhauled recently because it is very clean! Is there a diagram or pictures of what the linkage and cables look like correctly attached to this carb? I can try and attach pictures later, if it helps? Thank you everyone for the help.

Edited December 7, 2016 by HEC1

[Plymouthy Adams]

I may be out of line on the Sisson choke.....often I forget that all items are not on all lines of vehicles across the line up...

[Dodgeb4ya]

Probably not enough manual choke and maybe a faulty accelerator pump circuit.

The carburetor choke plate must close all the way with the choke knob pulled out. Choke is really only needed on a cold start. 

The accelerator pump jet when looking down the carb should squirt a full long shot of fuel every time the throttle is opened.

 

[HEC1]

this is a picture of the linkage on the manifold to the carb.

[Jeff Balazs]

There are several things that could contribute to hard cold starting. The overall condition of the engine may be part of it. Have you done a compression check? Or taken vacuum readings on it once it has warmed up? Also just because the carb looks clean there is really no reason to think it is functioning as it should. If it has been sitting for a while the leather on the accelerator pump plunger may have dried out. How about sediment in the float bowl? Another thing to check is float level. Also it may be worth checking the fuel pump pressure and delivery rate.

Without knowing anything about the condition of this truck it is difficult to say why it is hard to start. There could be some minor things in the ignition system contributing as well. If it were me I would start off with hooking up a vacuum gauge once it is warmed up and see what it tells you. Doesn't cost anything and it can tell you a lot.

Jeff

[Merle Coggins]

It looks like you are missing the hand throttle cable. That wouldn't effect the cold start.

As mentioned, remove the air filter and check that you have a good spray of gas down the throat of the carb when the linkage is actuated. If you are getting a good squirt, then maybe you just need more choke to start cold. While you have the air filter off you can also check that the choke is functioning properly too.

 

[jeffsunzeri]

All really great suggestions.

To completely check the choke circuit:

1. With the air cleaner off, pull the choke control out and determine where the butterfly valve is fully closed. That is the setting you want to use on a very cold start.

2. Check the choke butterfly to make sure it has mechanical integrity, and some of them also have a spring loaded air valve which must be checked for free movement at this time.

3. When the choke is full on, it should rotate a small cam under the idle screw via a rod. If that is not set correctly, you will have to manipulate the throttle as Jeff has indicated.

4. When starting cold, leave the choke valve open (knob pushed in). Press the accelerator to the floor three times (to prime with fuel from the accelerator pump).

5. On the third pump, hold the accelerator to the floor (this allows the fast idle cam to come into play as well as let the air/fuel mix), and pull the choke knob to the full on position you determined in step 1.

6. Count to 3.

7. Release the accelerator and press the starter pedal.

 

Depending on the age of the engine, etc. you may find modifying the number of accelerator strokes, or the position of the choke may change. These things do have some individual idiosyncrasies!

 

Edited December 7, 2016 by jeffsunzeri

[Merle Coggins]

There is no fast idle cam on the truck carbs. They're pretty simple. The choke cable operates the choke only. If you want to raise the idle you need to pull out the Throttle knob slightly. But it appears that isn't connected in his picture.

[HEC1]

Thank you all for the input. I did pull the carb of and rebuilt it. everything was super clean, all the passages where clear. I checked everything according to the YouTube video I saw made by Mike from MikeCarburators. The only thing I found wrong was the float level was set to high. I made sure everything moved smooth and freely. I will prime the carb tomorrow and see how it starts, following the instructions given to me here. I will also check the vacuum and compression. I will let you all know what happens, thanks again!

[HEC1]

Thank you all for the input. I did pull the carb of and rebuilt it. Everything was super clean, all the passages where clear. I checked everything according to the YouTube video I saw made by Mike from MikeCarburators. The only thing I found wrong was the float level was set to high. I made sure everything moved smooth and freely. I will prime the carb tomorrow and see how it starts, following the instructions given to me here. I will also check the vacuum and compression. I will let you all know what happens, thanks again! This is how the carb looks now.

Edited December 8, 2016 by HEC1

[Jeff Balazs]

One more thing comes to mind. The accelerator pump linkage has 3 possible settings. This linkage connection would have been removed during disassembly. Perhaps it got put back together incorrectly? Or could be it is set for high altitude/hot weather now........

Jeff

[HEC1]

Thank you gentlemen for all the help and tips. Just to let you all know the truck is starting great now. The compression was 70 I think, sorry I forgot now, vacuum was a steady 19, timing is at 0. I added a throttle cable, now to start the truck I crank it over twice for 3 seconds each with the key off ,pull the choke cable out abut 1/4 from being closed, I pump the gas two times, on the second pump I set the throttle cable to 1/4 open, turn the key on, press the starter button and she fires off with in two revolutions of the starter motor. I know it sounds like a lot to do and very slow, but it really is not! The only car I can start faster is my 2003 Daily Driver! Thank you all so much for the help! I also want to say of all the different car/truck forums I am on, this one has been the nicest and friendliest by far!

 

Edited December 15, 2016 by HEC1

[P15-D24]

In the picture a spring is missing for the choke, so it won't set correctly when the cable is pulled out. 

[HEC1]

P15-D24, There is a really small spring on the back side of the choke linkage, you can barley see it in the picture. It is hidden just in front of the cable housing, you can see part of it just above the cable wire, if that's the one your talking about?

 

[Jeff Balazs]

Glad you got it figured out. Makes for a much better driving experience.

Jeff