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I keep running into different topics about the LGT2654 with a Kohler KT745.
Once again a lady let it sit outside for a couple of years without starting and I’m trying to help her out.
After today I need advice on a few things.
This mornin before I moved it to where I work on it I put a tiny Tach on the spark plug wire just to check rpms at low idle and full throttle. Then pulled it around to the front of my shop. Ran it about 10 minutes total. Went to remove my tach and the heat coming from the engine seemed a little much. I grabbed my ir gun and the oil area was 135 degrees. But the ohv covers where two different animals. Facing the front of the mower the one on the left was reading 195-200 degrees and the right cover 145-150 degrees. Both exhaust before going into the muffler where 200.
I decided to go ahead and pull the cowling off the top and see if it was full of debris or gunked up. I’m posting pictures of what I found. Nothing but rust and what looks like backed on oil from I think the valve cover on that side. I checked the bolts on the valve cover with the engine cool. I used my 1/4” torque wrench and the two on the bottom where loose so I got them to spec according to the manual I found on line.
I tried to slide a business card between the air gap on the flywheel and coils and not a chance. I opened up the manual on line again and got my feeler gauges.
The manual gives two separate settings. .008”/203mm and .012”/305mm.
I don’t know which one to go by but not even the .008 would fit.
In the old days I’d get out the wire brush and maybe emery cloth and clean the whole thing up. Which if I did remove the rust I think the .008” would fit.
Is there a better way of cleaning up this mess and stopping the corrosion?
Also in the pic’s there’s one of the coil wire where the silicone is cracked at the coil. Should I go ahead and replace? After looking at the pictures y’all may tell me to replace both of them. There’s a green wire in the picture that wasn’t hooked up to anything. If anyone knows what it’s for I’d appreciate that.
I really appreciate all the help y’all have given me so far. I’m ge y’all’s advice so I don’t throw parts at it that it doesn’t need. And I don’t end up taking apart something big I didn’t have to.
Thanks again for share your knowledge.
I see the one I started about the oil filter is still an on going debate.
I worked for an equipment rental company for 22 years and every good small engine mechanic I had wasn’t afraid to voice his concerns. The biggest one for all of them was how people treated the equipment. Especially chainsaws.

I would order new coil, green wire is possibly ground wire, check schematic in Service Manual above. Remove old coil & wire brush area on flywheel where contact is made. Air Gap on flywheel is 0.010, small business card works just fine. Make sure engine cooling fins etc, are clean as well as complete engine. Brake Parts Cleaner etc. may work on rust, dirt, & grease.

The gap simply changes the spark timing and on mower engines it is not all that critical.
Magnets should never be cleaned it is bad for them
the laminations can be cleaned but again apart from measuring the gap the rust makes absolutely no difference to the spark
Moving closer will advance the timing moving back will retard the spark.
It also changes the flux rate but contry to popular mis belief does not actually the voltage generated

mechanic mark said:

Free Kohler Service Manual Downloads - OPEengines.com

Listed below are Kohler engine service repair manual in Adobe PDF format that you can download for free. Below we have provided a link to these manuals which can also be download. Click on your engine listed below to download. These service manuals provide general information, adjustment...

www.kohler-engine-parts.opeengines.com

I would order new coil, green wire is possibly ground wire, check schematic in Service Manual above. Remove old coil & wire brush area on flywheel where contact is made. Air Gap on flywheel is 0.010, small business card works just fine. Make sure engine cooling fins etc, are clean as well as complete engine. Brake Parts Cleaner etc. may work on rust, dirt, & grease.

Click to expand...

Thank you Thank you! Ive found that different manuals say different things. Must be the different year models. I normally don’t worry about rust on the flywheel because I figure the magnet doesn’t care. But this was really built up. I took a fine brush on my Dremel and cleaned a lot of it off. Then set the gap between the coils and the magnet at .008 but I’ll change it to 0.010.
Im going to suggest to her to let me replace both coils. The other ones wire don’t look much better.
I forgot to mention I used one of the spark testers that goes inline with the plug and has a glass you can see the spark.
I saw spark on both but it wasn’t blue it was yellowish. Does that mean anything? Then I got out something I hadn’t used. Called an ignition spark tester that I can adjust the gap. I set it for small engine plugged it into the spark plug wire then grounded the other end. I never got spark to jump the gap on either one. I used it one time 2 years ago on my old outboard and it worked then. The 40 hp started when I pulled it and I touched the engine and got lite up. My grandson was standing there supposed to tell me if he saw spark. He looked at me said you ok Gpa. I said yes. He said good because I really need to laugh right now.
Is brake cleaner safe on the aluminum? I’ve been looking at degreasers and they all seem to be corrosive.

bertsmobile1 said:

The gap simply changes the spark timing and on mower engines it is not all that critical.
Magnets should never be cleaned it is bad for them
the laminations can be cleaned but again apart from measuring the gap the rust makes absolutely no difference to the spark
Moving closer will advance the timing moving back will retard the spark.
It also changes the flux rate but contry to popular mis belief does not actually the voltage generated

Click to expand...

Thanks for the information I appreciate it. I’ve already removed some of the rust from the magnets with a light brush and Dremel but I didn’t go to bare metal. It was really caked on and pitted looking. I’m going to suggest two new coils because the wires on these don’t look good where they enter the coils.
Does all that I mentioned about the temperatures mean anything?
Also the fins on the heads don’t have any debris in them but have corrosion. I’m trying to figure out what’s best to clean the engine with that won’t cause more aluminum corrosion. Once cleaned I’ll coat it with corrosion x aviation. All the degreasers I see are not safe on aluminum. I read a lot about Totally Awesome on line being safe. I called the company and was told do not use it on aluminum. I have a gallon of Purple power but it’s rough stuff.

Douglasdzaster said:

Thanks for the information I appreciate it. I’ve already removed some of the rust from the magnets with a light brush and Dremel but I didn’t go to bare metal. It was really caked on and pitted looking. I’m going to suggest two new coils because the wires on these don’t look good where they enter the coils.
Does all that I mentioned about the temperatures mean anything?
Also the fins on the heads don’t have any debris in them but have corrosion. I’m trying to figure out what’s best to clean the engine with that won’t cause more aluminum corrosion. Once cleaned I’ll coat it with corrosion x aviation. All the degreasers I see are not safe on aluminum. I read a lot about Totally Awesome on line being safe. I called the company and was told do not use it on aluminum. I have a gallon of Purple power but it’s rough stuff.

Click to expand...

Rust and corrosion will not affect the performance or longevity of engine as long as it is free from dirt, debris, and grass.
Blue spark indicates a nice strong spark, yellow a weaker spark. .010” on air gap on ignition coils. If you feel the need to scrub engine, use a small steel brush, try various cleaners, and air compressor.

Tiger Small Engine said:

Rust and corrosion will not affect the performance or longevity of engine as long as it is free from dirt, debris, and grass.
Blue spark indicates a nice strong spark, yellow a weaker spark. .010” on air gap on ignition coils. If you feel the need to scrub engine, use a small steel brush, try various cleaners, and air compressor.

Click to expand...

Thanks so much. How do I achieve the blue spark?
I just did a test spot with some Chemical Guys Sticky citrus wheel cleaner that’s the best thing I found that really gets my after market wheels clean of brake dust and everything.
I sprayed some on a rag and rubbed it on a spot where the aluminum had corrosion. Then rinsed it off and it cleaned it right up. I know it’ll take the oil and stuff off the frame for sure. Got a valve cover leaking on the mower also.
Trying to figure out how to remove the fender where the gas cap is so I can get to the fuel tank and replace the fuel hose and vent hose. I noticed where the plastic clips into the metal but it’s super tight. I’m going to pull the wheel of and see what else is holding it on. I have a trim kit for such things just gotta figure it out.

Yeah I get a little crazy about cleaning,detailing and shining everything. I’m going to wash out all the dirt and debris and call it good. I’m already spending way more time on this mower than expected.
I’ve got fishing that I have to get done.

Hey guys another question. Before reassembling is there something I can spray the starter with for cleaning and to lubricant or protect?

I thought I’d go ahead and test the coils ( for educational purposes)I’m going to replace anyway because of the cracks I found where the wires are weathered at the coils.
So here I go on YouTube again. A lot of videos the guy seems to put all sma engines in the same category measuring ohms they should only read 2-5.5k I believe is what it was. He tested one and it was over 9 so he said it’s about to stop working.
The manual doesn’t give a spec for the resistance in ohms instead it says you have to have a specific coil tester and it’s done by spark.
I set my multimeter to 20k ohms and used a clip for one wire and connected it to the bolt hole where I knew I had good contact then put the other wire into the spark plug wire and both coils measured a little over 11k. The removed the tester from the spark plugs wire to the kill tab and #2 had 9k and #1 said 10k.
Can someone tel me if I’m doing this correctly and if these readings are good. When I tested spark it before disassemble it had yellow/weak spark on both cylinders. So I used my other tester which is adjustable as to how far the spark can jump and when I set it for small engines neither one would make the jump.
I’m about to contact my neighbor I’m doing this for and let her know what I’ve spent on parts and what else I’ve found that she needs. I’d like to tell her how the coils tested along with its a good idea because of it being outside for so long.
EDIT: I looked up ignition tester for Kohler and found the adjustable spark tester I just told y’all about. I would’ve stuck them back on today to test but I finished doing the leakin valve cover last night and waiting the 24hr cure time. Which as hot as it is here it’s probably cured early.

OK
First of all you are doing things the wrong way round.
You ask here first , get told the truth then go on You tube to try and find some one who knows what they are talking about ( cuts out about 75% of them ) then watch how they do it .
If the coil has a remote control unit ( often called an exciter ) then you can test it with an Ω meter and the engine manual will list the limits .
If the coil has an embedded Hall Effect trigger chip in it then it becomes a "Module" and it can not be tested with an Ω meter other than a secondary reading on the HT side .

Now fools skim through a manual and see some numbers then they decide that the numbers for a specific engine must be the same for all engines and publish total BS on You Tube .
Once upon a time I tried to correct some of them but that always results in me being abused, flamed & trolled by the presenters loyal disciples who will not tolerate any criticism of their messiah .

To test a module you need an oscilloscope plus the appropriate signal generators and even a flux generator, thousands of dollars worth of gear to test a $ 40 part .
Now the output of a module gets tested with a variable gap meter
B & S make a simple 2 gap one which gives you a pass / fail result or you can get any one of a number that have a moving contact that can be moved further apart till the spark can no longer jump the gap.
However to be of any meaning full value you need to know things like the number of turns on each winding within the coils the strength of the ignition magnet, the air gap between the coil & magnet the air pressure & humidity in your workshop , your altitude etc etc etc .
So in reality a good / bad test is quite enough
The resistance of AIR at 150 psi over a 0.030" gap is roughly equivalent to the resistance of AIR over a 0.50" gap at sea level .
This is how those old Champion plug testers worked
They had a trembler coil in them that produced a consistent stream of sparks and you increased the air pressure around the spark plug till the spark stopped jumping the plug gap .
A great toy for convincing a car owner that perfectly good spark plugs needed to be replaced

And a word of warning about using those sliding contact spark testers
If you are still generating pulses from the engine and the resistance at the testers gap is too great for the electricity to jump then YOU can become the conductive path OUCH or even RIP so you only widen the gap to .05" or till the spark stops whichever happens first .

bertsmobile1 said:

OK
First of all you are doing things the wrong way round.
You ask here first , get told the truth then go on You tube to try and find some one who knows what they are talking about ( cuts out about 75% of them ) then watch how they do it .
If the coil has a remote control unit ( often called an exciter ) then you can test it with an Ω meter and the engine manual will list the limits .
If the coil has an embedded Hall Effect trigger chip in it then it becomes a "Module" and it can not be tested with an Ω meter other than a secondary reading on the HT side .

Now fools skim through a manual and see some numbers then they decide that the numbers for a specific engine must be the same for all engines and publish total BS on You Tube .
Once upon a time I tried to correct some of them but that always results in me being abused, flamed & trolled by the presenters loyal disciples who will not tolerate any criticism of their messiah .

To test a module you need an oscilloscope plus the appropriate signal generators and even a flux generator, thousands of dollars worth of gear to test a $ 40 part .
Now the output of a module gets tested with a variable gap meter
B & S make a simple 2 gap one which gives you a pass / fail result or you can get any one of a number that have a moving contact that can be moved further apart till the spark can no longer jump the gap.
However to be of any meaning full value you need to know things like the number of turns on each winding within the coils the strength of the ignition magnet, the air gap between the coil & magnet the air pressure & humidity in your workshop , your altitude etc etc etc .
So in reality a good / bad test is quite enough
The resistance of AIR at 150 psi over a 0.030" gap is roughly equivalent to the resistance of AIR over a 0.50" gap at sea level .
This is how those old Champion plug testers worked
They had a trembler coil in them that produced a consistent stream of sparks and you increased the air pressure around the spark plug till the spark stopped jumping the plug gap .
A great toy for convincing a car owner that perfectly good spark plugs needed to be replaced

And a word of warning about using those sliding contact spark testers
If you are still generating pulses from the engine and the resistance at the testers gap is too great for the electricity to jump then YOU can become the conductive path OUCH or even RIP so you only widen the gap to .05" or till the spark stops whichever happens first .

Click to expand...

I know you’re right about me and you tube. I still go there after figuring out it was not a good place to learn about my outboard motor.
You are also correct about the adjustable spark tester. I bought it for the outboard I was working on. Turned it to the setting the manual said. It was on the back of the motor and I had to get in the boat to pull start the 40hp. So I pulled and it started. I went to lean around to try and look at it instead of getting out(safer).
And Im not sure if it was the bottom cowling the head or what. I have known idea where it came from but I got jump started. I could have sworn I heard someone yell CLEAR and wam I was being lite up like Christmas in the park. My teenage grandson made sure I was ok then couldn’t stop laughing saying you should have seen your face and eyes.
Let me ask you this. The spark I got from the mower wasn’t a good blue it was yellow/orange which tells me it’s weak. The mower sat outside in the elements without being started at least 18 months. Since I checked the spark I’ve taken cover and shrouds off to get to everything and spent most of yesterday cleaning it up and removing corrosion along with taking apart all the electrical connections and cleaning them. After it’s bath I repaired a leaking vale cover and let it set today for the sealant to cure real good. After cleaning the cover I sat it it a piece of clean glass and made sure I couldn’t slide a feeler gauge underneath it.
Also the battery was probably low when I checked the spark which I charged it yesterday while cleaning. I have the new fuel line but discovered that epa vapor hose cracked ever where and after running around tomorrow looking for replacement hose I want to put everything back together and test the spark again. Then figure out how I’m going to get the new hoses hooked up to the fuel tank without removing the mowers body. I just need to get under the fender where you adjust height but it don’t want to budge.
Good job calling me out on those few things. I needed it.
It was a forum like this one that saved me during my boat rebuild. I now know that outboard inside and out. And I have a thick pair of rubber gloves and s set of hose pliers of different sizes with a long reach Incase I want to remove a spark plug wire to check one of the three cylinders.
Thanks for the information. Sounds like the on way I’ll know if a module is bad is if it doesn’t have any fire at all.

The spark from a magneto is exponentally related to the speed the magnetic field cuts through the coil
At cranking speed you are at the very bottom limit so you get a cruddy spark
You need to test it at operating speeds , that is what is important
You just need enough of a spark at cranking speed to ignite the charge every now & then .

bertsmobile1 said:

The spark from a magneto is exponentally related to the speed the magnetic field cuts through the coil
At cranking speed you are at the very bottom limit so you get a cruddy spark
You need to test it at operating speeds , that is what is important
You just need enough of a spark at cranking speed to ignite the charge every now & then .

Click to expand...

Makes sense. Thanks for your reply.

Douglasdzaster said:

Makes sense. Thanks for your reply.

Click to expand...

It is not that all of YouTube is bad for small engines, or any other topic for that matter. The issue is, you gotta sort through the garbage to get to the gold. If you don’t have much knowledge or experience, you may think the garbage is gold.
everytime someone asks about testing a coil (or a lot of other questions for that matter), and Bertsmobile answers by typing copious amounts of typing, that takes time and effort. I’d say some of these questions need to be a sticky. Testing coils is just one step that can be done, it is not definitive usually. The 2.5 to 5 ohm reading is for a 4-5 horsepower push mower engine, not a 22 hp twin.

Well I did start a thread for people who do know to recommend You tube channels worth looking at and from memory there is only 5 recommendations to date
The current server does not do stickies