Carb adjustment

I filled up the gas tank last week and the weather has gotten hot.  The Jeepster has been running worse and worse.  I popped the spark plugs out and found this sooty mess.  I have been thinking it is running rich and I thing the hot weather and summer blend gas pushed it over the edge.  I cleaned all the plugs and replaced them.

I leaned out the choke a few degrees.  It still feels like there is a lot of spring pressure on the choke but I need to wait until the engine is cold to mess with it.

I can mess with the idle mixture though.  I turned the screws all the way in carefully counting the turns.  The left screw was out 3 1/2 turns and the right 3 3/4 turns.  Considering the “starting point” is 1 1/2 turns that is a LOT.  Don’t know what I was thinking.  I got the engine hot and turned the screws in 1/2 turn at a time until the idle started to drop then backed off 1/2 turn.  They ended up at around 2 turns out so I was really rich.

I also took a look at the heat riser.  Mine turns freely (which is good) and the thermostat spring is intact(also good).  But that spring is supposed to be hooked behind the metal pin on the counterweight and I don’t see how.  The spring does not want to bend over far enough to hook behind the pin.  I am also not totally sure if this is the open or closed position (I think closed).  I will make some inquiries but I might have to take this thing off and debug it.

I was tired of wrenching so I spent a little more time and washed the Jeepster.  Much crap came out of places like the insides of the fenders.  Much water ended up inside the car.  But it does at least look a little cleaner and the top is a little whiter.  I should have taken pictures but I did not.

The next morning I took another look at the choke.  It seemed like I had to turn the choke spring a long way to take pressure off the choke plate.  I thought maybe the rebuilder had put the bi-metallic spring in backwards or 180 off so I took it off.  It sure looks OK but I will check.

This is the lever the spring pushes on to close the choke.  If everything is assembled correctly I would expect the spring to wind up tighter as it warms up.

Lets try it.  Here is the bimetallic spring at room temperature.

And after 30 seconds with a hair dryer on it.  So everything is assembled correctly, I just had too much tension on the spring.  As you can see it does not move far.

I put the spring in the freezer for 15 minutes then put in on such that it just barely pushed the choke closed.  Here is where it ended up.  You can see the condensation from the chilled thermostat.  We will run it this way a little and see how we do.

Update 6/14/2017

So it turns out we are not doing that well.   Maybe freezing the choke themostat was a stupid idea.  I took a look with the engine cold and found the choke was wide open.

I adjusted it to just be closed.  It is a hot day so this might be excessive.  You can see I turned the thermostat 10 or 15 degrees.  Baby steps.


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