Kohler v-twin engines

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Recently I saw a new Kohler v-twin engine on a zero turn with the oil pan off. Was surprised to see a plastic cam gear and plastic governor gear which had broken. It was a new machine. I've always liked Kohler engines but I won't buy an engine with plastic gears. The new Toro commercial v-twins have plastic cam gears. The new Briggs Commercial Turf does Not have plastic gears in it. Not sure about Kawasaki but don't think so.
 
Two different Kohlers:

Command = Good
Courage = garbage

Which was it?

LOTS of small engine makers use plastic cams, even Briggs & Stratton.
 
Likely a Kohler Courage with plastic cam gears. One of the worst engines ever produced. I've seen the plastic cam gears break, head gaskets blow multiple times, oil leaks, bolts back out and smack the flywheel, and the blocks crack from weak metal.

Briggs single cylinder smaller engines (5-6hp or so) have nylon camshaft gears, but I haven't had any issues with those yet.
 
Originally Posted By: Linctex
Two different Kohlers:

Command = Good
Courage = garbage

Which was it?

LOTS of small engine makers use plastic cams, even Briggs & Stratton.

I don't remember but it was on a 60" Big Dog z-turn. I would say it was a Command. It was at the dealer and he was surprised to see that also. It was a new mower in his stock. He starts them to move them outside and lets them run for a while to warm up the oil.
 
Commands don't have plastic cam gears. The Courage engine is an overhead cam engine with the plastic gears.

Courage has replaced Command in a lot of applications because they are much cheaper. I see new zero turns all the time with these Courage engines, and other Chinese clones.

Courage cam gears:

maxresdefault.jpg
 
Originally Posted By: cronk
Almost every small engine is going to have a plastic (nylon) governor gear.
The plastic cam gear or cam would turn me off though.


That would be true.

My neighbour's lawnmower kept dangerously over-revving (B&S engine). Upon inspection the nylon governor gear had come apart.

I loath the idea of plastic internal engine parts and will go to great lengths to avoid buying anything with plastic internal parts.
 
Like said above, I don't care for the Kohler Courage single cylinder series of engines. Some aspects of the design are good, but the whole package is not. OTOH, I find the Courage V-twin series of engines to be good. I have not known anyone with them to have issues. I had one on a ZTR for a few years and liked the engine.
 
Originally Posted By: boraticus
Originally Posted By: cronk
Almost every small engine is going to have a plastic (nylon) governor gear.
The plastic cam gear or cam would turn me off though.


That would be true.

My neighbour's lawnmower kept dangerously over-revving (B&S engine). Upon inspection the nylon governor gear had come apart.

I loath the idea of plastic internal engine parts and will go to great lengths to avoid buying anything with plastic internal parts.


Even the legendary Honda GX engines use a plastic governor gear!
 
Originally Posted By: JTK
Like said above, I don't care for the Kohler Courage single cylinder series of engines. Some aspects of the design are good, but the whole package is not. OTOH, I find the Courage V-twin series of engines to be good. I have not known anyone with them to have issues. I had one on a ZTR for a few years and liked the engine.


+1
 
Originally Posted By: cronk
Originally Posted By: boraticus
Originally Posted By: cronk
Almost every small engine is going to have a plastic (nylon) governor gear.
The plastic cam gear or cam would turn me off though.


That would be true.

My neighbour's lawnmower kept dangerously over-revving (B&S engine). Upon inspection the nylon governor gear had come apart.

I loath the idea of plastic internal engine parts and will go to great lengths to avoid buying anything with plastic internal parts.


Even the legendary Honda GX engines use a plastic governor gear!


What's this world coming to?

Seems Honda is prone to using plastic internal parts in some of their engines. That's disappointing. Nonetheless, their GX series engines are indeed legendary. Wonder how long they've been using plastic governor gears?
 
On the courage I think it is important to prefill the filter as full as possible per the instructions. They have no oil pressure until it fills.

I do know of one where the owner did not prefill his. Putting it on dry is good enough for his car, good enough for the mower. The rod parted company with the crank at about 100 hours. I got mine at the same time, it now has about 250 hours, it is 7 years old so has had 7 changes. Still seems good. That is still many hours away from acceptable. maybe I am just lucky.

Rod
 
Do the Courage single cyl engines have full pressure lubrication? Most make/models don't. The oil pump just circulates oil through the filter. Some have top bearing pressure lube and splash lube for the crank end and con rod.
 
Last edited:
Originally Posted By: boraticus
Originally Posted By: cronk
Originally Posted By: boraticus
Originally Posted By: cronk
Almost every small engine is going to have a plastic (nylon) governor gear.
The plastic cam gear or cam would turn me off though.


That would be true.

My neighbour's lawnmower kept dangerously over-revving (B&S engine). Upon inspection the nylon governor gear had come apart.

I loath the idea of plastic internal engine parts and will go to great lengths to avoid buying anything with plastic internal parts.


Even the legendary Honda GX engines use a plastic governor gear!


What's this world coming to?

Seems Honda is prone to using plastic internal parts in some of their engines. That's disappointing. Nonetheless, their GX series engines are indeed legendary. Wonder how long they've been using plastic governor gears?



The Honda GC engines that have the overhead cam and use a timing belt have a plastic cam gear. I haven't seen any issues with it though, likely because it is connected with a belt.
 
Kohler states full pressure lubrication with oil filter and bypass valve. I just scanned the factory manual for the single cylinder, I did not find a oil system drawing, it kind of looks like all the lube oil is filtered before the bearings, but someone who has disassembled and engine and traced the passages will know for sure. The crank is cross drilled for positive pressure lube. A filter bypass valve would not be needed if the filter was a bypass filter. It is possible the lower main is unfiltered oil and upper main and rods are filtered. They state to pre-fill the oil filter, to the bottom of the threads and allow time for the oil to soak in, so it certainly seems to be filtered thru the filter before going to something important.

Rod
 
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^ Thanks Rod. Makes sense to me. Plus the Courage singles I've seen had vertically mounted oil filters anyway, so pre-filling and getting them threaded back on is simple.
 
Originally Posted By: boraticus
Originally Posted By: cronk
Originally Posted By: boraticus
Originally Posted By: cronk
Almost every small engine is going to have a plastic (nylon) governor gear.
The plastic cam gear or cam would turn me off though.


That would be true.

My neighbour's lawnmower kept dangerously over-revving (B&S engine). Upon inspection the nylon governor gear had come apart.

I loath the idea of plastic internal engine parts and will go to great lengths to avoid buying anything with plastic internal parts.


Even the legendary Honda GX engines use a plastic governor gear!


What's this world coming to?

Seems Honda is prone to using plastic internal parts in some of their engines. That's disappointing. Nonetheless, their GX series engines are indeed legendary. Wonder how long they've been using plastic governor gears?


I tore into a well used Honda GX that was from the 1980's and it had a plastic governor.
This is nothing new.
The legendary Kohler K series also used nylon governor gears starting in the mid to late 70's if I recall correctly.
 
Drives me crazy, what could they save between plastic and steel? $15? Id gladly pay it. Ive had a few Courage engines open, and would not buy any machine with one on it, and thats from a guy who loves magnums, commands and especially K series. Its a shame Kohler went this route and hasnt seen the light yet.
On the other hand the fantastic Kawasaki fd620d used in a ton of top tier super garden tractors used plastic cam gears until 1998, when they saw the light. Sad they didnt provide free cam gears for replacement, but at least they changed to steel.
Never fails, money just makes people make dumb decisions.
 
Quote:
Drives me crazy, what could they save between plastic and steel? $15?


Bean counters rule the day in many companies. Seen questionable methods, practices, and
designs in autos, outboards, snowmobiles, OPE's etc.

Some times it works and others not so much.
Early attempts at liner-less motors (outboards) were flawed and costly
for warrantee depts.
Japan seems to have figured it out, at least Honda has.
Still, that's been limited to entry level push mowers, etc...

My 2¢
 
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