49 cub starter/magneto

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Re: 49 cub starter/magneto

Postby firetech » Sun Oct 21, 2012 6:44 am

I no longer have the battery hooked up because I killed the starter. I wasn't too bothered cuz if I get the tractor started or in running condition I will have starter rebuilt and reinstall it. But for sure the throttle plate is in the closed position while attached to governer rod. While in bed (cuz this whole thing has consumed me) thinking about the possibilities it kinda makes sense that I am getting gas out the front of carb because while cranking - if the vaccuum is sucking fuel out of the bowl and the fuel is stopped by the throttle plate - it would then accumulate at the bottom of intake and spill out. Is this all possible? Is there a way to trick this? if possible I would like to isolate the carb issue ( get it kinda started and then concentrate on carb). I know I am beating a dead horse here but If tractor was running recently and at this point I have spark should that not mean - all electrical is in order leaving somekind of fuel issue?

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Re: 49 cub starter/magneto

Postby Eugene » Sun Oct 21, 2012 9:58 am

Take a break from the tractor. I don't know what the problem(s) is or are. Attack the problem(s) one system at a time. First check for compression on each cylinder. Dry compression test should suffice. Then move on to ignition timing. Lastly the carburetion/fuel system.
firetech wrote:- if the vacuum is sucking fuel out of the bowl and the fuel is stopped by the throttle plate - it would then accumulate at the bottom of intake and spill out. Is this all possible?
If you have a vacuum (engine compression), then the air fuel mixture, an atomized vapor, is reaching the cylinders.
I know I am beating a dead horse here but If tractor was running recently and at this point I have spark should that not mean - all electrical is in order leaving some kind of fuel issue?
Not necessarily. Check the ignition timing with a timing light at hand cranking speed. Timing spot on, then check the routing of the spark plug wires from the distributor to the correct spark plug.
I have an excuse. CRS.

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Re: 49 cub starter/magneto

Postby lazyuniondriver » Mon Oct 22, 2012 12:37 am

Eugene wrote:
lazyuniondriver wrote:Give it a week or two, you'll get the urge to tinker with it again, not wanting to let a simple machine get the best of you.
I don't think there is anything seriously wrong since the tractor was running 5 days previous.

I've gone back to page one of your trip and after all we have checked and tested, I concur with Eugene that there was probably nothing seriously wrong with your tractor to begin with and there is still nothing seriously wrong with it other than the smoked starter.

I tend to think originally damp weather combined with an engine in need of a tune up fitted with marginal parts prevented the tractor from starting.

You mentioned the tractor was never good at being hand crank started to begin with. The worse the engine is out of tune, the less chance of you successfully cranking it up by hand.

You have come to a fork in the road that is going to cost you money. If you sell the tractor as is, you'll get beat up on the non-running price costing you money as you cannot defend the engine, trans, finals, or hydraulic systems condition. This should prompt you to spend the money on the repair parts to get you up and running and keep the tractor too.

Hand cranking this tractor with air, fuel, and ignition systems all tampered with will be very difficult to say the least.

Pull the starter and replace it with a known good replacement or preferably, have yours rebuilt.

Get a new battery or have yours load checked and if in serviceable condition, have it fully charged.

If the battery cables have been replaced with anything less than what came from the factory, remove and replace. If the cables are of the proper size, replace the ends if they are not in perfect condition.

Leave the points and condenser alone for the time being since we have spark. Since we believe dampness caused all this grief to begin with, buy a cap, rotor, plugs, and wires.

Remove the plugs, remove the distributor cap and replace the rotor.

Since the plug wires have been off and on frequently, we need to make sure they are not a problem. Crank the engine to number one coming up on compression, stopping when the mag clicks lining up the timing pointer on the pulley notch as you described you did previously.

Install your new correctly gapped plugs.

Move to the distributor and verify the rotor is pointing to the position of number one on the cap tower. Snap the cap on and route the first wire from the tower of the cap the rotor is pointed at to the number one plug.

Follow the cap clockwise, next cap tower wire to plug three, next cap tower wire to plug four, the last wire to plug two. Add the coil wire but not before checking the inside of the coil wire tower on the mag for dirt and corrosion, cleaning if necessary.

The closed throttle plate doesn't sound legit since it was running 5 days ago but since you've had the carb off, double check to ensure the choke pull rod is on the front choke shutter and the throttle rod from the front governor rockshaft is on the top throttle plate. Also until it starts, leave the kill switch wire disconnected although I doubt the switch or wiring is to blame.

With the fuel on, speed control lever halfway forward and with no choke, transmission in neutral, pull the starter. Hopefully success.

Once it starts, let it fast idle to operating temperature then make your idle mixture and curb idle adjustments.

If it cranks for 10 seconds but fails to give an indication of any attempt to start, stop cranking for a minute to cool the starter.

Close the choke and crank for another 10 seconds. If it doesn't start or is dripping gas, chances are something in your carb rebuild job went amiss.

Pull the carb, rebuild it using a fresh rebuild kit and no used gaskets. Reinstall and retry the starting procedure over again starting without choke. If you have access to a spare carb known to be fully functional, swapping them out now would be wise.

We all know this will set you back close to a couple of Benjamin's however spending the money now will provide you a tuned tractor for several years and a good starter for another 50 or 60.

Good luck and let us know what happens once you get everything straightened out.

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Re: 49 cub starter/magneto

Postby firetech » Mon Oct 22, 2012 1:23 pm

well its sold - $950 can dollars. Sad to see it go but felt my hand was forced. Either way this is how it ended -

-compression was at 83-86 per cylinder ( not bad I thought) and that was dry tested,

-timing was correct ( TDC then checked rotor and it was at #1 plug wire on distributer cap), listened to mag click just as it reached TDC mark on fan belt pulley, mag would click twice per revolution,

-wiring of plugs from cap all correct 1,3,4,2,- spark all the way to plugs ( verified spark individually by pluging spark plug in wire, grounding out plug with jumper cables, while in the dark got nice blue arc), I did not completely redo the mag cuz I felt it unneccessary do to all else appearing in order.

-recleaned and ensured cap and rotor were clean and shiny (wire attachment on dremel tool) all good and I was already getting spark but for the sake of completness I redid it.

-did verify that all valves were in working order ( removed side plate, hand cranked, and watched as every valve operated with engine turning),

-Reinstalled carb verifying proper rod connections (choke and govener),

-managed to get starter operational ( playing with connection within starter housing),

-gas on and attempted a start in the normal fashion and nothing, tried various different ways and still nothing, last resort I attempted gas again directly into cylinders to try to at least get a pop but nothing.

- I did not get chance to rebuild carb, 2-3 day wait on delivery of kit from local tsc store. So I was left with the decision of wait for kit and attempt rebuild or take buddys offer before he changes his mind.

Lastly but most important is I want to say thank-you to everyone who assisted me and tried to rectify my issue. The only way I will try again is if buddy fails to bring the money. But it does leave me bewildered as to what thing so serious or minor could have caused me so much grief>>>>>>>> again thankyou.

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