[gy67]

I have another thread started about the problems I have had with my 140 and 49 blower. I am now tired of throwing money at this thing hoping that the next item I replace will take care of my problem so I am starting over.
What I have: 1969 140 - (converted to points) Engine rebuilt less then 5 hours ago. Bored, new piston, rings, rod, valves, points condenser etc..

Problem: Engine cuts out or pops and cracks after about a 20-30 min. while running the snowblower. It ran great for the first 3 to 3.5 hours I ran it this Fall while using it for leaf pick up. During the first snowfall this year it blew a head gasket before I even turned on the snowblower. It was running in the garage to warm up a little before I started. I installed a new head gasket the next day and it ran good for 20-30 min then started the popping and cracking problem. I took the head off had my Deere dealer machine it flat brought it home installed it with a new head gasket torqued down to 30 ft # in 10# increments in order according to the Kohler manual ran it for about 30 min. and re-torqued the head. Took it out and it is still doing the popping and cracking after a few min. of run time.

What I have already done:
*Machined head
*New plug
*Checked points and cond.
*New plug wire (8mm)
*rebuilt carb and then replaced it with another carb off my 120.

Is it possible that the coil may be bad. I always thought a coil was either good or bad but I'm probably wrong. I am thinking of replacing the coil next to see if that clears it up but I would like your opinions here before I buy one to try. My Deere dealer has one in stock but I was wondering they are the same one I can get at NAPA or someplace else and save myself a few dollars. Sorry for this long post but I am at a loss here as to what I can do to fix this thing.

 

[woodpecker41]

If it was mine I would replace condenser. The symptoms of a bad condenser are it causes the engine to start missing after a few minutes to 1/2 a hour of run time. My experiences have shown me that there are a lot of new condensers for Kohlers that are bad out of the box. My friend restored a beautiful CC 100 and IIRC the fifth new condenser was the first one to let it run longer than 5 to 10 minutes. I myself have started using the Transdenser that Kirk Engineering sells. It replaces the original condenser with a points triggered electronic ignition in a container the size of the original condenser case. Roger

 

[gy67]

Ok today I borrowed a spark tester from a friend and have found that the spark plug is firing consistently when the motor stumbles so does that mean I have valve problem?

 

[Greenguy_140]

Brad, have you figured out the prob yet? I'm thinking that a spark tester wont show any probs a bad condenser will cause. Still could be the condenser in my guess. Have you swapped out a few? I've had bad ones in an old jeep back in the day...they do make life miserable. I tore into the V-8's timing case to check timing (which of course was ok) then when totally weary I tossed in another condenser. It idled like a beauty....had the neighborhood mechanics shaking their heads as they would never have guessed that to be the prob.

Try two seperate condensers to see if the behavior changes..if not, then try a compression test to see what's up.

And yes, you most likely can pick up the coil at an auto parts store to save a buck or two (I know our auto value has them)

Good luck!

Ryp

(Message edited by GreenGuy_140 on December 22, 2005)

 

[rchristensen]

Brad B.
I have seen a couple of different problems with bad coils. One coil caused a normally good starting Kohler to start hard, required just the right amount of choke but once it fired it ran good. Other coils will break down when warm, usually you can feel them on the side and they are real hot, eventually they will fail completely.

If you buy a coil from a Auto store be sure you get the one with the built in resistor.

I don't know what type of spark plug you are running but if it is a Champion I have had bad luck with them I use a Autolite 216 and have had good luck with them. If you just used an in line spark tester it probably only tells you that you are getting spark to the plug, some plugs will not fire under compression.

Another thing to check is your wiring. A bad wire between the points and coil, maybe shorting out or bad end connectors. Also if your switch is bad (high resistance) or wiring on the 12 volt supply will drop the voltage to the coil.

 

[gy67]

UPDATE:
Put refurbished head on two weeks ago used the tractor for less then an hour before it started popping and cracking again. Shut it down and left it till after the holidays. Took it over to my neighbors heated garage yesterday thinking that the valves may be out of adjustment but found on one of the towers that the head bolts go through was cracked. Got excited that I finally had my problem whipped I ran across the street pulled the head off my running 120 bolted it on started it up let it run and it started popping again. It only does this lightly at first when at full throttle but after it warms up then it gets worse. It starts easy and idles great but once you throw the gas to it and bring the RPM's up it starts the cracking & popping. I checked the RPM's at full throttle and it checked out at 3,400 that should be good shouldn't it? I let the tractor cool down for about 2 hours outside brought it back in and checked the valves. They both spec'd out according to the manual. What is left??? I am going to try and different set of points and condensers this weekend if that's not it I am at a complete loss as to where to go next other then pulling the motor and doing a "Monster Garage" job to it with a few of the fire arms I have in my small collection.

 

[andys_212]

Brad-are your valves seating okay? I'm guessing they would be good if you rebuilt the engine recently because you would of cut them with the specialty carbide cutter and/or lapped them when putting it back together?

Just a thought. Hope you get it figured out.

 

[gy67]

Yes the valves seem to be seating OK. I checked them also when I had the head of yesterday. This is probably the 5th or 6th kohler I have rebuilt in as many years and the only one that has ever given me this much trouble. Thanks the advise though I will take all I can get. I'm sure that there is something that I am forgetting that will fix this problem. I keep hoping that if I pester your WFM'rs enough someone will come up with the cure.

 

[gy67]

What should the points be set at? Should they be set hot or cold?

To date I have check or replaced with no luck:
head, head gasket, plug, plug wire (3 times), condenser, coil, rebuilt 2 different carbs, cleaned gas tank, new fuel filter and line, checked valves.

If somebody can get back with me on how the point should be set that would be great.

 

[stanb112]

Set the points to .020" hot or cold, doesn't matter.

 

[gy67]

Thanks Stan I'm going out now to check that. I pray to the John Deere Gods that this will be the problem as I am at a total loss if this doesn't tun out to be the problem.

(Message edited by gy67 on January 02, 2006)

 

[stanb112]

Brad, I suggest you remove the points to clean the pivot shaft and the plastic. I've found points with a heavy buildup of dark gunk on the pivot which causes sluggish movement of the movable block. Also make sure the pushrod is clean and moves freely in the engine block. Stan

 

[gy67]

Thanks for the idea on the points Stan I will check those and clean as needed on Wednesday. I did however put my test light on the positive side of the coil while it was running and found instead of a light that is on solid it will flicker. It did this even at idle when the motor wasn't sputtering, is that normal? I would think that the test light light should be on solid all the time.

 

[stanb112]

The positive side of the coil should show a solid +12.6 to +13.8 volts, the same as at the (+) battery terminal. Your flickering indicates a definite problem somewhere between the battery, ignition switch and coil. I'd suspect the switch first. Old ignition switches are famous for having bad contacts and I'd replace it unless it's relatively new. I'd also remove the wiring connector and clean the terminals on the switch and in the connector. Finally, I'd carefully inspect the wire running from the switch to the coil for frayed or cut insulation and partially broken wires at either end. Look for possible shorting where it runs under the engine. Let us know what you find.

 

[jjenson]

I'm looking for a wiring diagram for a L111 as my friend has quite a few gremlins to discover. It was acting strange prior to when he hooked the jumper cables up in reverse and now has no response whatsoever. Prior to the jumper fiasco, he had a dead battery and jumped it. It would kill a couple seconds after removing the jumpers. Any ideas of where to start with this one?