Kohler Command CV730 low on power

[cbs123]

Hello all,

I have a 25 HP Kohler Command CV730 in the shop. I've been through the carb, replaced fuel lines and filter, fuel pump, spark plugs, tested compression (135 on each cylinder) Set RPM's at 3400. It cranks and runs really good until you put a load on the motor. Then it is very weak. When it came in, neither coil was firing. I happened to have a Kohler 7000 series 25 hp on the floor that had ran out of oil with only 50 hours on the motor. I decided to take it apart to see if the coils were the same. Well, the part # on the coils was different, but they had the same bolt spacing. I put them on it and they both fire and the engine runs.

My question is, could there be a difference in these coils causing the low power problem? I'm beginning to think the timing may be slightly off due to variances in the coils???? Never heard of that, but can't figure out why this motor is weak. It doesn't smoke or anything unusual, just low on power.

Any advice greatly appreciated. Thanks

 

[ILENGINE]

Kohler has used about 10 different coils with different firing times, some use different flywheels also. Post the model and spec from both engines and we can do some comparison with parts.

 

[cbs123]

Kohler has used about 10 different coils with different firing times, some use different flywheels also. Post the model and spec from both engines and we can do some comparison with parts.

Ok, here's the info. The motor I'm working on must've had the shroud replaced or something, its got a blank sticker over the model that has #CV740-0036 wrote in permanent marker. The bad coils that came off the motor have part # 24-585-45 on both of them. I didn't write down the # of the coils I put on it, but the engine model # is KT745-3087. It sounds like it's possible that the timing is off from what you are saying, but wouldn't it cause it to run poorly all the time? instead of just under a load? At this point, that's all there seems to be left. It bogs when you turn the blades on, or just driving it up an incline.

 

[ILENGINE]

The 24 584 45 is used on a CV730 but not a CV740 which is a CDI fixed timing ignition.. The KT745 uses a 32 584 09 or 32 584 24 or 32 584 25 which is the MDI variable timing module.

 

[cbs123]

The 24 584 45 is used on a CV730 but not a CV740 which is a CDI fixed timing ignition.. The KT745 uses a 32 584 09 or 32 584 24 or 32 584 25 which is the MDI variable timing module.

ok, thanks for the info. The coils I took off must've been on there awhile. plenty of rust and looked original? Strange to have two bad coils at one time though? although this mower has been sitting for awhile. What coil should be on the CV740? If this is in fact a CV740. Like I said, the original sticker is covered by a new blank sticker with CV740-0036 written in permanent marker on it. According to what I looked up, the part # for that model should be 24 584 36-s, not 24 584 45. There is no ignition advance module or anything on this engine, just a single white "kill" wire going to the coils.

I would greatly appreciate any info you could share on this. I've got almost a full days work on this motor, and to not be able to get this last piece of the puzzle figured out is a little disappointing. Not to mention the customer is wanting his mower back. I appreciate the help.

 

[ILENGINE]

If the 24 584 45 coils where installed I would suspect that this is a CV730 engine not the Exmark CV740-0036 that the model number points to.

 

[StarTech]

Strange to have two bad coils at one time though?

Not really I had two last year that were supposedly under warranty to go bad at the same time on the same engine. At Kohler said they were under warranty and for me to carry to a local Kohler dealer to get them made but of the local would do it stating that if they didn't sell the equipment they were not honoring the Kohler warranty so I am out $86 for the two coils. Glad the customer reimburse me for the coils after he found what Kohler and the dealers did to me. The shop where he brought the ZTR was running three months behind and he was needing his mower for his lawn care business.

 

[cbs123]

If the 24 584 45 coils where installed I would suspect that this is a CV730 engine not the Exmark CV740-0036 that the model number points to.

It WAS the coils. Put the correct part # coil on and it runs good and has power now. Thanks for the help

 

[ILENGINE]

Thanks for letting us know was the final resolution was.