No idle on 1904
- Thread starter Maughan
- Start date
Robert Kenney
Super Moderator
Did the no idle condition exist with the old main well? Where is the idle mixture screw set? Other things outside of the carb can cause a lack of idle.
Never tried running the old main well, it was missing parts. The idle screw showed no effects to the idle. I turned it all the way in, and removed it while truck was running to no effect. The motor was up to temp, and I was nursing the truck with the choke just to keep it running.
I'm thinking I need to soak it again and be more precise in making sure it's really clean, before trying it again.
A little history on the truck, it was sitting for 3 to 4 years. The fuel was really gummed up.
I'm thinking I need to soak it again and be more precise in making sure it's really clean, before trying it again.
A little history on the truck, it was sitting for 3 to 4 years. The fuel was really gummed up.
Scoutboy74
Moderator
Has all the old fuel been drained, or are you still trying to run it on aged gas? Maybe try running from a jockey can of fresh fuel until the onboard fuel system can be purged of varnish.
Robert Kenney
Super Moderator
Ok I found it finally. I posted a port diagram a while back and just found it.
http://www.forums.IHPartsAmerica.com/carb-tech/3757-1904-problem.html#post27816
You May need to save these images to your computer and open them in the windows viewer so you can zoom in on the text.
If you look at the green text (sorry it is hard to read) you can see where I noted the idle discharge ports on both the carb body and main well. The port on the main well contains the pilot jet orifice. The port on the body connects to the idle mixture screw and the transition holes under the throttle plate. Some where in the idle circuit there is a blockage. Start at the pilot jet in the main well. It is so small that it can become blocked even if the main well had had a thorough cleaning. With carb cleaner and compressed air, blow through the main well passages after probing the pilot jet with a small wire. Do this several timed untill satisfied things are clear.
Remove the mixture screw and blow out the idle circuit passages
in the carb body till you see flow through all visible holes.
Before attempting to run it as scoutboy stated make sure you have fresh fuel and a good filter just before the carb.
http://www.forums.IHPartsAmerica.com/carb-tech/3757-1904-problem.html#post27816
You May need to save these images to your computer and open them in the windows viewer so you can zoom in on the text.
If you look at the green text (sorry it is hard to read) you can see where I noted the idle discharge ports on both the carb body and main well. The port on the main well contains the pilot jet orifice. The port on the body connects to the idle mixture screw and the transition holes under the throttle plate. Some where in the idle circuit there is a blockage. Start at the pilot jet in the main well. It is so small that it can become blocked even if the main well had had a thorough cleaning. With carb cleaner and compressed air, blow through the main well passages after probing the pilot jet with a small wire. Do this several timed untill satisfied things are clear.
Remove the mixture screw and blow out the idle circuit passages
in the carb body till you see flow through all visible holes.
Before attempting to run it as scoutboy stated make sure you have fresh fuel and a good filter just before the carb.