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Excellent forum; what a community!
First post for me.

I have a Kohler KT 715 (7000 Elite Series, 20hp, Spec PS-KT715-3041, Serial 4613304884) motor in a riding mower/tractor that is giving me some trouble.

The symptoms are rough starting, starter binding up, not turning the flywheel, and I have to boost power to the battery with a jump and/or help turn the flywheel by hand while I have the key held in start. I have installed a new starter, new solenoid, and battery is great (I've tested with different batteries, and by jumping). Also the starter is getting the 12+ volts to it when I try to start it.

Once it runs it is fine. It seems like this has been going on for about a year, but has gotten worse somehow and now is a real problem.

My research indicates that I'm down to a couple of things this could be. 1. The ACR is broken, 2. the valves are out of adjustment, or 3. something like fluid building up in the cylinders??? - but that seems like a stretch.

One thing I can't isolate is whether or not this motor actually has an ACR. Parts of the manual indicate it does, and parts indicate it does not.

Any thoughts or diagnostic steps on this would be super appreciated.

Thanks you all,
Matthew

Looking at the camshaft for your engine it doesn’t appear to have an ACR mechanism. First thing I would do is check and adjust the valve clearance. This service manual should help you. https://resources.kohler.com/power/...89.244229191.1690221632-2069592575.1690221632

Thank you so much for the service manual. The only manual I had so far was the owners manual that came with it and the troubleshooting portion said it could be the ACR. I'm encouraged to know that it might not even have one!!! Valve clearance could cause something like this (make it super hard for the starter to turn the motor over)? I'll make the valve clearance my next check.

actionmatthew said:

Excellent forum; what a community!
First post for me.

I have a Kohler KT 715 (7000 Elite Series, 20hp, Spec PS-KT715-3041, Serial 4613304884) motor in a riding mower/tractor that is giving me some trouble.

The symptoms are rough starting, starter binding up, not turning the flywheel, and I have to boost power to the battery with a jump and/or help turn the flywheel by hand while I have the key held in start. I have installed a new starter, new solenoid, and battery is great (I've tested with different batteries, and by jumping). Also the starter is getting the 12+ volts to it when I try to start it.

Once it runs it is fine. It seems like this has been going on for about a year, but has gotten worse somehow and now is a real problem.

My research indicates that I'm down to a couple of things this could be. 1. The ACR is broken, 2. the valves are out of adjustment, or 3. something like fluid building up in the cylinders??? - but that seems like a stretch.

One thing I can't isolate is whether or not this motor actually has an ACR. Parts of the manual indicate it does, and parts indicate it does not.

Any thoughts or diagnostic steps on this would be super appreciated.

Thanks you all,
Matthew

Click to expand...

Yep, no ACR on any current production Kohler Twin Cylinder engine except in very specific applications.
Before you go too far, are you able and willing to do one simple voltage test?

Absolutely, what did you have in mind? Thanks!

actionmatthew said:

Absolutely, what did you have in mind? Thanks!

Click to expand...

Take your voltmeter and simply attach the black lead to the negative terminal of the battery. Then take the red lead of your meter and touch it someplace on the case of the starter that is unpainted. Typically, I usually go to the drive end housing near the mounting bolts. Crank the engine and see if you read any voltage. You should read zero. If you do read voltage, then you have a compromised ground. Possibly where the ground cable connects to the equipment. Ground issues are pretty common on some of these pieces of equipment so it’s always a good idea to eliminate that first as it’s very easy to do and might save you from chasing other things that aren’t actually a problem.

Super doable. I'll check that out before I start the valve inspection/adjustment.

The manual references an ACR under troubleshooting. Super confusing, Kohler! Am I right?

Not reading any voltage with that test you recommended, so that's good. Here is a video from earlier that shows a bit of how it sounds when it actually does start to turn over again and again, I had the choke off so it would not start but the sound is interesting I think. I still have not checked the valves, but that's next.

Sorry, this link might work better https://drive.google.com/file/d/1pIyCicSABpL4vuHJibmmLv5NdJsmgaPd/view?usp=sharing

actionmatthew said:

Sorry, this link might work better https://drive.google.com/file/d/1pIyCicSABpL4vuHJibmmLv5NdJsmgaPd/view?usp=sharing

Click to expand...

After throwing parts at it with no change, most likely will be valves out of spec all along. Adjust valves correctly and see how she starts.

actionmatthew said:

The manual references an ACR under troubleshooting. Super confusing, Kohler! Am I right?
View attachment 66038

Click to expand...

Yeah unfortunately it's a fairly generic troubleshooting list. Everything they list doesn't always apply to your specific engine.

I thought I'd jump back on with an update. You all were correct; it was the valves. I can't believe how much just a little out of spec can make a huge difference. She's running like a top now. I really appreciate the help.

I know this sounds wrong, but when it does not start, could you try a quick shot of starting fulid or similar. I just want to rule out fuel 100%. We have not ruled out fuel.


also:
when not starting, pull plugs, blow out cylinders by running starter, then attach plugs and try again. this rules out fouled and crap in head.

just for crap and giggles, lets get a compression test in these cylinders. Lets get back to basics. I like to rule out everything easy.

sorry missed above update somehow. My error.

jviews12 said:

I know this sounds wrong, but when it does not start, could you try a quick shot of starting fulid or similar. I just want to rule out fuel 100%. We have not ruled out fuel.


also:
when not starting, pull plugs, blow out cylinders by running starter, then attach plugs and try again. this rules out fouled and crap in head.

just for crap and giggles, lets get a compression test in these cylinders. Lets get back to basics. I like to rule out everything easy.

Click to expand...

IT'S RUNNING GUY. No need for starting fluid.

Read the post right above yours. Guy must be a bot. Admin alert!!!!!

actionmatthew said:

I thought I'd jump back on with an update. You all were correct; it was the valves. I can't believe how much just a little out of spec can make a huge difference. She's running like a top now. I really appreciate the help.

Click to expand...

yup...it does make a difference even when valves are just a little out of spec. The valves get worn (or the seats of both) and then the valve get tighter with too much clearance. Or the other way, with soot that prevents the valves from seating. With twin cylinders even just one valve out of lash can cause "timing" problems.

most mowers call out a "big 300 hour" maintenance schedule to perform valve lash and also valve cleaning. for new engines that see lots of work..I prefer to do this sooner than the 300 hour mark.

I had the sa

actionmatthew said:

Excellent forum; what a community!
First post for me.

I have a Kohler KT 715 (7000 Elite Series, 20hp, Spec PS-KT715-3041, Serial 4613304884) motor in a riding mower/tractor that is giving me some trouble.

The symptoms are rough starting, starter binding up, not turning the flywheel, and I have to boost power to the battery with a jump and/or help turn the flywheel by hand while I have the key held in start. I have installed a new starter, new solenoid, and battery is great (I've tested with different batteries, and by jumping). Also the starter is getting the 12+ volts to it when I try to start it.

Once it runs it is fine. It seems like this has been going on for about a year, but has gotten worse somehow and now is a real problem.

My research indicates that I'm down to a couple of things this could be. 1. The ACR is broken, 2. the valves are out of adjustment, or 3. something like fluid building up in the cylinders??? - but that seems like a stretch.

One thing I can't isolate is whether or not this motor actually has an ACR. Parts of the manual indicate it does, and parts indicate it does not.

Any thoughts or diagnostic steps on this would be super appreciated.

Thanks you all,
Matthew

Click to expand...

I had the same issue on a Cub Cadet with Kohler engine. Kohler redesigned the starter for that engine. The new part number is 32-098-10S. Idon"t know if you replaced with the old number (32-098-08S). The new starter is smaller, has more torque, and spins the engine over quickly. Hope this helps, I had a runaround and went direct to the Kohler website.

Hi, I have the same engine and always wouldn't start if warm. Adjusting the
valves fixed it, starts hot or cold now. It did this from factory with less than 20 hours.
Good luck!

actionmatthew said:

Excellent forum; what a community!
First post for me.

I have a Kohler KT 715 (7000 Elite Series, 20hp, Spec PS-KT715-3041, Serial 4613304884) motor in a riding mower/tractor that is giving me some trouble.

The symptoms are rough starting, starter binding up, not turning the flywheel, and I have to boost power to the battery with a jump and/or help turn the flywheel by hand while I have the key held in start. I have installed a new starter, new solenoid, and battery is great (I've tested with different batteries, and by jumping). Also the starter is getting the 12+ volts to it when I try to start it.

Once it runs it is fine. It seems like this has been going on for about a year, but has gotten worse somehow and now is a real problem.

My research indicates that I'm down to a couple of things this could be. 1. The ACR is broken, 2. the valves are out of adjustment, or 3. something like fluid building up in the cylinders??? - but that seems like a stretch.

One thing I can't isolate is whether or not this motor actually has an ACR. Parts of the manual indicate it does, and parts indicate it does not.

Any thoughts or diagnostic steps on this would be super appreciated.

Thanks you all,
Matthew

Click to expand...

It sounds to me possibly Vacuum Lock.
I've had the same problem & changed battery, Starter solenoid & starter motor without success.
I now switch off fuel tap at the end of each mow & I have never had another problem.
Try It & let me know.

Rod