Kohler CV750 Problem. Need Help Please!

[tlmarrio]

I have a Kohler CV 750-0026 with 1900hrs on it. It has been very well maintained. Recently while mowing it would run very strong and then drop a cylinder. At first it only lasted a second or two before going back to full power. Then it seemed as time went on it would stay on one cylinder longer and longer.I replaced the carb with a new one with no change. I identified which cylinder was acting up and replaced the coil which seemed to help some but continued to act up so I replaced the second coil also with no change. The spark plugs are new,along with the fuel filter and fuel pump.I still have the problem. It seems to me it gets worse when it is hot outside. If this were fuel related wouldn't both cylinders cut out?A Kohler tec said it sounds like a valve sticking from time to time but before trying to tackel that major undertaking (on set requires pulling the engine)I thought I would see if anyone on this site may provide some insite.The problem is driving me crazy and as you can see you can toss alot of money at it in a hurry. Any help would be greatly appreciated.

[piston slapper]

Did you replace the harness between the coils?
The coils and harness usually come in a kit...
As a precaution..it is advisable to install an inline fuse holder on the power wire that goes to the regulator...20 amp fuse...this will prevent your ignition from power spikes created by the stator and regulator..
Try this...when the engine is running poorly...slowly pull the choke...
If it smoothes out...it might be a leaking intake gasket...
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[tlmarrio]

Thank you piston slapper. Neither coil (DSAI)came with a wire harness.They pluged into a three pronged circut next to where they bolted on. There is no gap to set on these coils also. I am sure new that. Just in talking with different people it sounds like this model of engine had different coils at one time? As I said replacing the coils seemed to help but it still happens just not as bad. (yet) I have messed with the throttle and choke while it was happening and it did not seem to make a difference however, I did not try pulling the choke slowly like you mentioned. I have to mowe tonight and will try when it acts up. Again seems to be more of a problem while running on a hot day verses a cooler one. Thanks for the reply.

[tlmarrio]

Hello Piston Slapper.
I can't seem to find a part number for this wiring harness you a referring too looking at the online parts place. Do you have any idea where i can get it?
Thanks. By the way I mowed last night for about 1 and a half hours temperatures in the 70's and it only did this a couple of times.Each time it was so fast I did not have a chance to try and pull the choke slowly like you suggested. By the way you staying above water down there? Hope all is well for you!

[Sharpcut 1]

You should of got the improved coil kit with the new wiring harness, comes with both coils and harness. There is a service bulletin, I believe SB300, which gives you the kit numbers.

[piston slapper]

Thanx Sharpcut...I've replaced a few of those kits..and couldn't find the old boxes to get a part number...I haven't been a Kohler authorized dealer since last october....starting to miss all that inside info...
All this rain has created a new job...spent all day removing the foot pedal chains on all the Dixie Choppers...and retiming them for maximum height...
The ground and grass is so saturated that the mowers are losing 1 to 2 inches of cutting height....fun...fun...fun...
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[fixer67]

I could not find SB-300 online b ut I did find this.

[tlmarrio]

Hey All thanks so much for the information. This one has really got me going in circles however I do believe it is a electrical issue and not fuel related. Since I already purchased and installed the two new modules do you think I can purchase the wiring harness seperatly? I will see what i can find today. Thanks again. When I finally track this problem down to the end I will report back my findings so that someone else may benifit from the information. I can't believe that I am the only one outthere witht this problem.

[piston slapper]

Go ahead and install an inline fuse holder on the middle wire going to the regulator..
A couple of months ago I had a CV750 that was burning up 1 coil every 2 weeks..
I installed the inline fuse and it has been running fine ever since...
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[tlmarrio]

Thanks for the advice slapper. Ordered harness today. It will be a week to get it delivered. The inline fuse you are referring to goes to the rectifier/regulator that is on the outside of the motor? Once again I appreciate your assistance. Hope your drying out dowm there!