Farmall Cub no start no cough

Hello, trying to see if anyone can help thru this dilemma.

Some backstory, I have owned a Fcub for ~25 years now, ran it for approx 3 years cutting grass and then parked it in a family member's barn (basic dry storage). Ran and had power but had various electrical issues with charge and discharge of the battery. Retrieved last year and just started working on it this spring.

12v neg conversion, rebuilt wiring harness.

Soaked carb 2x in the "paint can" solvent, rodded out all the holes and orifices except I did not take off the idle tube.

Timed engine by removing #1 spark plug, set by visualizing piston movement and valves stationary +/- 20 deg of the 2nd TDC notch on the crank pulley. Set rotor to this point. Getting healthy spark. Set 1342 order in a clockwise orientation as viewed from the driver's seat.

Here is where I'm stuck. I can crank and crank with more speed than ever before. But I'm getting no cough, no hint of trying to fire.

Some steps I tried...sprayed starting fluid in the air intake tube...reversed the 1342 firing order of wires by 180 deg just in case I did choose the "wrong TDC". Placed a drizzle of marvel mystery oil in all cyls in case valves were sticking.

I am getting fuel to the carb, seems like a reasonable amount out of the steel tube. Verified screen is clear. Opened bottom plug on the carb and a lot runs out followed by same flow as above. Tried choke/no choke/throttle closed, throttle WOT.

I realize I should probably check compression, could attempt the idle tube removal, I have thought about pouring a small amount of fuel in each cyllinder thru the spark plug hole to see if that helps.

Checking in to bounce off ideas and see what suggestions you have, I am mildly frustrated :shock: but not ready to give up Thanks for your time.
 
Sorry, a couple of clarifications after re-reading my post...

12v negative ground conversion from original 6v positive. 30A mini alternator. Verified proper voltage to distributor.

After I reversed the plug wires, I started the timing procedure from the top, verify TDC + no valve motion 20 deg either side of TDC, then replaced 1342 order.

I do have a little fuel dripping out of the intake side of the carb. The needle valve is free but obviously not seating 100%. I do recall this being identical to before. If the engine was stopped and fuel not shutoff under the tank, a few drips would remind you to do this step. But as soon as it was running, it was all good. It is a slow drip, lets say 1 every 10 seconds. I did replace the carb gasket with a new genuine CaseIH part I had from 20yo ago, just a cork gasket but NOS at that point.
 
Re: the spark, I have checked coil to center wire = ok and checked the other 4 cyls with a 5th plug just laying on a metal part of the engine. While I can't assess the mechanical "time" of the spark it is visually reaching all positions.

I'm a victim of my own "was running when parked" representation (!!)
 
Pull the plugs and make sure there not wet because it they are wet they are fouled and need to be cleaned or replaced. Gas dripping form the carb is pretty normal when trying to start an engine. You might also try this. Hold you hand over the air intake of the carb and spin it over. You should both feel a good suction and get gas on your hand. It may even try to fire up or fire up when you do that
 
Thanks all, I did look at all the plugs again and they are pretty carboned up, especially down in the cavity between the insulator and the body (there might be a better term for this). Going to get new plugs. The 'Net says they are stocked locally at CarQuest.

Also found a pin was lost out of the throttle linkage down-front-underhood. Then I could control the throttle position better.

I tried Old's suggestion of hand over the intake, it does have excellent suction, but this didn't do the trick.

Verified fuel flow again, let gasoline run out of the bottom plug in the carb bowl for a couple of minutes (back into a clean can for recycling)

Tried a mild amount of spark (distributor base) advance, this seemed to help very slightly. Tried several positions along the way.

Ended the evening with what I can tell are combustion noises with closed throttle, full choke, but not enough to pull away from the starter.
 
Thanks all, I did look at all the plugs again and they are pretty carboned up, especially down in the cavity between the insulator and the body (there might be a better term for this). Going to get new plugs. The 'Net says they are stocked locally at CarQuest.

Also found a pin was lost out of the throttle linkage down-front-underhood. Then I could control the throttle position better.

I tried Old's suggestion of hand over the intake, it does have excellent suction, but this didn't do the trick.

Verified fuel flow again, let gasoline run out of the bottom plug in the carb bowl for a couple of minutes (back into a clean can for recycling)

Tried a mild amount of spark (distributor base) advance, this seemed to help very slightly. Tried several positions along the way.

Ended the evening with what I can tell are combustion noises with closed throttle, full choke, but not enough to pull away from the starter.
 
Thanks all, I did look at all the plugs again and they are pretty carboned up, especially down in the cavity between the insulator and the body (there might be a better term for this). Going to get new plugs. The 'Net says they are stocked locally at CarQuest.

Also found a pin was lost out of the throttle linkage down-front-underhood. Then I could control the throttle position better.

I tried Old's suggestion of hand over the intake, it does have excellent suction, but this didn't do the trick.

Verified fuel flow again, let gasoline run out of the bottom plug in the carb bowl for a couple of minutes (back into a clean can for recycling)

Tried a mild amount of spark (distributor base) advance, this seemed to help very slightly. Tried several positions along the way.

Ended the evening with what I can tell are combustion noises with closed throttle, full choke, but not enough to pull away from the starter.
 
Just an update, I got 'er running :D

I got new Autolite 386 plugs, they didn't have the Albert Champion UD16s that I started with, but at $1.99 each I didn't complain.

This did make a slight bit of difference as I got a few more puffs and I had a couple instances where it would just barely run for 5 seconds.

A dozen or so attempts to restart while tweaking various throttle and choke positions, being able to barely putt putt along for about 10 seconds max here or there, it was like I suddenly sucked out a cobweb and in 2 seconds time the engine was idling smooth with nice throttle response. I don't know if it was an actual intake blockage or if it was a fuel system blockage, I really did nothing to the ignition other than the plug change.

I really hated to shut it off, but it starts easily over and over now, just a bump of the starter and its running.

Time to do an oil change and refill hydraulic fluid, I can hear the pump whine.

Thanks again for your ideas and help!
 
Does the tractor have a mag or distributor? Either way pull the cap and verify you
have spark across the points just visually. It should be very noticable. If not run
some emery cloth or a point file across the points. Many times they get oxidized from
sitting. Assuming you have compression you just need to verify gas, spark and timing
and she will run.
 
Glad shes running! IMO I would have tried getting it running again prior to all those upgrades. Then run it after each add on. It makes it so much easier to trace down problems. If it ran when parked it shouldn't need the timing adjusted for example and the crab cleaning would probably be all that was needed. Once you verify the carb and the tractor is running well... frankly I'd probably stop right there! But if you want to do the other upgrades, you have a much better point to start from with finding any issues.
 

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