cub won't start

[Phillip W. Lenke]

I recently restore a 49 cub. Had the engine gone through. mag rebuilt.
Carb rebuilt. I had it running a couple of weeks ago. now it will not run.
I have excellent spark. would fouled plugs not let it start.
Troubled pwl
HEELLLP!

[allenlook]

I'm assuming from your post it turns over and sparks, but never shows a sign of life?

Does it catch or sputter but just not run, or does it never even catch?

Might be a problem with fuel supply, are you getting fuel to the cylinders OK?

[Phillip W. Lenke]

It has excellent spark. I don't have a electric start on it yet I'll bet I could have cranked out 30 Gallons of Ice cream as much as I was cranking last night.
I cleaned the plugs and put back in and acted like it wanted to fire but cranking more . It would'nt go . I was able to crank over about one quarter turn before.
I have fresh gasoline in it . Has to be something I'm missing.
PWL

[allenlook]

Spark and fuel and air are the three major components. - are you getting a fuel/air mixture to the cylinders?

You've got spark, so that's OK... Now you need to find out if you're getting the fuel/air mixture into the cylinders to meet up with the spark...

Take out a plug and crank it over, after the compression stroke on that cylinder, do you have fuel/air in the cylinder?

Is something keeping the fuel/air from getting into your cylinders? Is your fuel line plugged or shut off? Did something build a nest in your air intake overnight? Between the robins and the mud wasps I have to keep things cleared out all the time around here.

[Phillip W. Lenke]

Took the carb off and completely cleaned all the jets , as was on one post.
I opened the end plug on the carb and fuel came out . I have good fuel to carb.
I did pull the plugs after excessive cranking and found they were wet ith
Fuel. Now, I did loose a pin that attaches the govenor to the carb to regulate rpm ,engine raced. until I go off it and go it shut it down. But I had it running after that . So I don't think I did damage there.
I'm perplexed, I dont know if the plugs are to fouled. I cleaned them and replaced. That was when it popped like it wanted to start then quit.
Never really stated though
PWL

[Bigdog]

Phil, change your sparkplugs. Put new ones in.

[George Willer]

Phil,

This is one that can drive you nuts!

Let's go over the things necessary for the engine to run.

1. fuel... check

2. compression... check (I think)

3. ignition... check

4. all the above happening at the right time. (maybe not)

I see two possibilities

#2... is it possible an intake valve spring either broke or lost its' keepers? An engine can't run unless the intake valves all close on cue.

And #4... to rule out the chance the gear in the mag slipped time, use the plug laying on the block to assure the spark for #1 or #4 occurs exactly when the pointer aligns with the notch in the pulley.

I thought I'd share the picture you sent of that beautiful paperweight!



See you Sunday. I hope you have good news to report.

[Mag Man]

hey phil,
I would double check the timing and make sure its not off 180 or somrthing. Do the crank untill # 1 is coming up on compression stroke and line the pointer up and check where the rotor is pointing on the cap. See if thats the problem.
JON

[George Willer]

Phil,

I just came in from getting Shorty running again. It was a head scratcher as well. Turns out the new condenser was shorted internally, so he is running just fine now on the old one.

If I understand correctly, your Cub had been running fine so everything was set up correctly? My response above was based on that assumption. Everything was great, but now it won't crank start?

Will it help if I lend you a starter?

[Phillip W. Lenke]

Well got home from work. Changed the spark plugs put autolights in took champions out, only used them for 2 weeks fouled pretty bad (as opposed to pretty good.) heard bad things about them. Can't believe it but it runs. Bigdog can't hide the engine problems from you either. Thanks for all the help fellows. Who would have thought! George, all the way home I was thinking about that spring , not wanting to get back into the valves and head. Thank God it wasn't . Still have carb issues. Not sure what it is but leaks past the float. Took the intake off tonight puddle of gasoline.
Thanks for talking me down.
Phil