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Does a NYLON Gear on cam sound like a good choice for longevity ? Thanks for any advice & input.

The Confidant is a fairly new Engine from Kohler, announced on Oct 21, 2013 to be ready for 2014 & up.

Kohler Engines introduces its Confidant engine series. This vertical-shaft, V-twin engine line was carefully designed to meet the unique needs of both commercial equipment users and property owners.

• Encompasses four models ranging from 19 to 25 hp
• Includes cast-iron cylinder liner to protect the engine in extreme operating conditions, dual-seal air filter to keep debris out of the engine; and high-torque inertia drive started with extra-large output for quick, reliable starting
• Pressure lubrication keeps critical parts protected
• Features Kohler’s PRO Performance Filtration package, a heavy-duty professional filtration bundle that includes a 3,500 cm[SUP]2[/SUP] air filter, a 6.5 gram oil filter, and a 9-12 micron fuel filter
• Includes Quiet Cam technology which consists of a rounded cam lobe and solid nylon gear that work together to help reduce sound levels

No But that is not why it is put in the engine. It is for money. One penny saved is a penny earned. It will be designed so it will last to at least the warranty time. Anything past that and you are a winner.

I had a Kohler Courage that like many other s the block cracked after most of the bolts came loose on top. I am attaching the parts pictures for you to get the full flavor of plastic.

Well, I certainly appreciate the replies. It's my thought as well. (cheep). This could be a deal breaker for me to get a Toro Titan.

I have a Kawasaki Timecutter 4260 that runs flawlessly. But I'm gonna call Kohler & inquire about how many other engines are using Nylon gears inside.

Thank You both. I know there were problems with the Courage. Thanks for the pics, too.

BlazNT- What engine is in your Z ?

Rocky J said:

I had a Kohler Courage that like many other s the block cracked after most of the bolts came loose on top. I am attaching the parts pictures for you to get the full flavor of plastic.View attachment 30196View attachment 30197

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OTOH did you have any problems with the gears ?
Occasionally I see the Govenor let go on these engines but seldom a problem with the gears.
In fact I have a few here where the counterweight let go totaling the engine, but the plastic gears are perfectly good although the cam shaft was bent like a bannana.

The crack has nothing to do with the plastic.
It was the end result of substituting a cast malleable iron crank for a forged high alloy crank.

And while we all go tut tut tut , cheapness, there is only one reason for making them chaeaper.
Because of all the tight fisted bastards who want a cadillac quality but are only willing to pay Pinto prices.
Think of a high quality mower maker and most likely the one you are thinking of went out backwards.
Honda made top shelf engine good for 50 years but not enough people would pay the extra $ 500.
Then the same cheapskates complain when products get downgraded to a level where the factory can survive on the price they are willing to pay.

Bottom end mowers come with junk engines and better ones come with a variety of engines.
Now most mower companies would be a lot happier only offering their mowers with one engine and a top one to boot so reducing warranty hassels.
But if they did that & the competitor fronts up with a mower of similar specs fitted with an Iseel Fromu Chinese engine $ 200 cheaper their sales for the year would be almost nothing.
The fact that Harbour Freight, Lowes & Walmart who only sell junk are more & more profitable every year while all the other retailers are going out backwards is all the proof a reasonable person needs.
IT IS NOT THEIR FAULT
IT IS THE DIRECT CONSEQUENCES OF THE SPENDING HABITS OF THE MAJORITY OF THE PUBLIC.

So Bert- Thank you for your input. DO you think the new Kohler Confidant with solid Nylon cam gear is worthy ?

I don't find any Nylon gears in my Kawasaki 651V engine tho.

7394 said:

So Bert- Thank you for your input. DO you think the new Kohler Confidant with solid Nylon cam gear is worthy ?

I don't find any Nylon gears in my Kawasaki 651V engine tho.

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Very few plastics are 100% plastic.
They put all sorts of fillers in there, particularly really toxic ones like cadmium Yellow.
100% nylon is very tough.
We used to cut rear sprockets out of 100% nylon billets and they outwore alloy ones and were only marginally weaker than steel .
There is not much force on those gears, all they do is compress the valve spring.
The tiny amount of give in nylon will soften the shock of the cam slamming into the cam follower just a little bit.
The trick is to make the cam wheel big enough to reduce the load per tooth to well under the load limit of nylon.
Better still, the larger the gear wheel the more accurate the timing

Re: Kohler Confidant uses Solid NYLON Gear on Cam, Sound like good idea ? Input Ple

Bert- Thank You Sir, as always I appreciate your input.

It's a new release engine (2014) from Kohler, that's why the concern on my part. I do feel better about the solid Nylon gear now.

The Kawasaki I have now has been in production for many, many years, & has great reputation. (decisions, decisions)..

7394 said:

Well, I certainly appreciate the replies. It's my thought as well. (cheep). This could be a deal breaker for me to get a Toro Titan.

I have a Kawasaki Timecutter 4260 that runs flawlessly. But I'm gonna call Kohler & inquire about how many other engines are using Nylon gears inside.

Thank You both. I know there were problems with the Courage. Thanks for the pics, too.

BlazNT- What engine is in your Z ?

Click to expand...

V twin Courage Pro 24 hp. Darn good motor.

bertsmobile1 said:

OTOH did you have any problems with the gears ?
Occasionally I see the Govenor let go on these engines but seldom a problem with the gears.
In fact I have a few here where the counterweight let go totaling the engine, but the plastic gears are perfectly good although the cam shaft was bent like a bannana.

The crack has nothing to do with the plastic.
It was the end result of substituting a cast malleable iron crank for a forged high alloy crank.

And while we all go tut tut tut , cheapness, there is only one reason for making them chaeaper.
Because of all the tight fisted bastards who want a cadillac quality but are only willing to pay Pinto prices.
Think of a high quality mower maker and most likely the one you are thinking of went out backwards.
Honda made top shelf engine good for 50 years but not enough people would pay the extra $ 500.
Then the same cheapskates complain when products get downgraded to a level where the factory can survive on the price they are willing to pay.

Bottom end mowers come with junk engines and better ones come with a variety of engines.
Now most mower companies would be a lot happier only offering their mowers with one engine and a top one to boot so reducing warranty hassels.
But if they did that & the competitor fronts up with a mower of similar specs fitted with an Iseel Fromu Chinese engine $ 200 cheaper their sales for the year would be almost nothing.
The fact that Harbour Freight, Lowes & Walmart who only sell junk are more & more profitable every year while all the other retailers are going out backwards is all the proof a reasonable person needs.
IT IS NOT THEIR FAULT
IT IS THE DIRECT CONSEQUENCES OF THE SPENDING HABITS OF THE MAJORITY OF THE PUBLIC.

Click to expand...

That courage had 68 hours on it. The problem had nothing to do with Nylon parts. If I had to blame something it would be dull drill bits,wore out tapes leaving a 50% thread contact on all the hole they drilled, not sure if thread locker would have held them.Workmanship not Nylon. I have been seeing Nylon for some years on tear downs but never the reason for the tear down. I am attaching a picture of a 6.5 Briggs Nylon Camshaft , it was a bent crankshaft from mowing fence post again Nylon had nothing to do with it. I am sure Kohler will be carefull after the Kohler Triad walk of shame.

And the Triad wasn't a nylon problem either. It was due to the one piece block with the pressed in cylinder liners from the bottom of the crankcase that would move like the valve guides on the briggs heads do when they overheat. They would slide down the bore, until the top ring would get above it and then pull the liner down into the crankcase breaking both rods.

Rocky J said:

That courage had 68 hours on it. The problem had nothing to do with Nylon parts. If I had to blame something it would be dull drill bits,wore out tapes leaving a 50% thread contact on all the hole they drilled, not sure if thread locker would have held them.Workmanship not Nylon. I have been seeing Nylon for some years on tear downs but never the reason for the tear down. I am attaching a picture of a 6.5 Briggs Nylon Camshaft , it was a bent crankshaft from mowing fence post again Nylon had nothing to do with it. I am sure Kohler will be carefull after the Kohler Triad walk of shame.View attachment 30212

Click to expand...

Nothing to do with bad machining or bad bolts.
It is a vibration affect that loosens the bolts allowing the crank case to flex then crack.
Each & every part that is moving inside the engine sets up a vibration at some particular speed these vibrations can become resonant and increase in magnitude by several factors.
It is these vibrations that undo the bolts and crack the crankcase.
The cure was not bigger , stronger , longer bolts or using thread locker.
The solution was changing the principle cause of the vibrations, the crankshaft.
When the engine was designed it used the forged Kohler crank.
For reasons of cost reductions ( most likely) this was changed to a cast crank.
Nothing wrong with that 1/3 of the cars use cast cranks on engines putting out 10 + times the Hp of the mower engine.
The CI crank is balanced by the counter weight and the primary balance is good, the engine is smooth in operation.
However there are secondary & tertiary vibration frequencies and the changes in these was not taken account for in the swap to the cast crank.
Bad tooling or assembly problems are easy to fix because the warranty control section would quickly recognise a cluster of serial numbers that had the problem then issue a dealer bullitin for rectification.
However a random vibrational failure is a different animal, very hard to diagnose.
I have about 20 or so customers with Kohler powered Huskys that have sequencial engine serial numbers, yet only 1 in that batch cracked.
Nearly all of the Kohler cracks are pre 2008 engines and there is almost nothing to connect them in useage conditions or operating hours.
The only connection is the front 4 bolts start to come loose so I just check them every service.
If they stay tight the case does not crack and it takes about 4 minutes to check them or an additional 30 seconds if you do scheduled service & remove the blower housing every year to clean the cooling fins.

Thanks everyone for all the input. & Rocky for the pics too. :thumbsup:

Guess I'm a lil shy of this new engine from Kohler (the Confidant). Since I could find lil to no feedback about it.

I know for a fact Kawasaki uses only Steel gears.

Only reason I was even considering an upgrade to the Toro Titan ZX4800 from my Toro SS4260 was they are really marked down from $5400. to $3999. End of this line close out sale.
And trading mine would make it much less yet. (too much thinking, I have a headache). :laughing:

Re: Kohler Confidant uses Soild NYLON Gear on Cam, Sound like good idea ?

OK, just learned Kohler has been using Nylon timing gear since at least 2007 even on the Commercial engines. Probably even earlier.

http://www.kohlerengines.com/press/article.htm?articleId=Feb07