Save me from burning her where she sits!

[Upstatehunter]

Again a 1960 Lark II 40 HP. Ran fine until the float went to crap and the fuel system got contaminated. Put new(tested) fuel pump on, new float, needle and seat. Cleaned the carb while I had it off to change the float.
Put it all back together and, no spark on lower cylinder. Changed the plug and had good spark. Started and ran the best it has since I bought it. Went to go this morning and figured better try it since it was still in the barrel.
Ran like crap, coughing and popping. Then quit and won't start. Fires but won't catch. Motor has new coils, points, wires. Had even 120 compression when I bought it. Made the guy check it right there to make sure. I'm real frustrated and about to burn the dang thing up and collect the insurance I put on it. Wouldn't be hard these old motor burn up all the time

 

[bktheking]

Re: Save me from burning her where she sits!

Burn it and take pics!

Seriously, same issue happens with my buddies 64. Is the idle needle loose to move or tight. The carbs on these motors are sensitive to change it seems and one slight move on the idle needle can mess up the cold start.

 

[Upstatehunter]

Re: Save me from burning her where she sits!

Needles are tight. Used my manuals starting points when I put it back together. Had to lean the idle very little. Was running great last Friday, went on a camping trip until Sunday, went out this morning and runs like crap. Nothing had moved or changed. Is about 10 degrees warmer and more humid. Acts like it is running out of fuel again. Keeps Sneezing and popping no matter where I change the low speed jet. Rich is worse. We even leaned the choke a little to help with a rich low speed. Didn't help.
Going to change out the plugs again.

 

[bktheking]

Re: Save me from burning her where she sits!

Check the threads where the plugs are, make sure they aren't being destroyed.

 

[Upstatehunter]

Re: Save me from burning her where she sits!

OK so what was the problem. Pulled the low speed needle. Cleaned, blew out with compressed air. Pulled th bowl on the fuel pump, cleaned it and the screen. Pulled the fuel pump cleaned the diaphram. Pulled the plugs and cleaned.
Running good again???
God I hope this thing isn't so tempermental that I have to do this everytime I want to use it.....

 

[Daviet]

Re: Save me from burning her where she sits!

You might want to think about replacing the fuel lines on the engine, could be coming apart from the inside.

 

[tx1961whaler]

Re: Save me from burning her where she sits!

Agree on the fuel lines. They are coming apart and messing things up.

 

[Upstatehunter]

Re: Save me from burning her where she sits!

It is less than 5 weeks old. When I got the motor I bought a new line. Took the tank, pulled the cap and the gauge fuel line hook up out. Cleaned the tank very well, then used a gas tank coat on the inside.(it didn't really look all that bad but wanted to be safe.) All the lines from the hook up to the fuel pump to the carb, even the vaccum lines are all new. At least they look good, and was told they were all replaced. I have noticed even in my can for my lawn mower a sooty looking material when the tank is emptied. I'm wondering if the station I'm getting gas from has dirty tanks and old filters. Very busy station though. Tried it this morning and fired right up, idles fine.
Picking up a new set of plugs. One question though. I put an In line filter just before the connection to the motor to try and catch some of the contaminates. Doesn't seem to be affecting it when it is running well. Would that make the carb need a different adjustment?

 

[Upstatehunter]

Re: Save me from burning her where she sits!

Going to pull the line from the fuel pump to the carb to see if it has this black sooty material in it.

 

[58RudeBigTwin]

Re: Save me from burning her where she sits!

I had similar problems and found the packing nuts around the needles were loosening while running. The needles didn't move (that I noticed), but when the packing nut backed out it would run awful. I tightened them more than I thought I should need to and it fixed the problem. Starts and runs fine now. Worth checking before getting the matches!

 

[tmcalavy]

Re: Save me from burning her where she sits!

Or you could have some skunky gas...try some fuel from another source.