Kohler vs. Tecumseh

[jellyghost 378]

I was recently offered a Sears St/16 at a fair price.  I really like 70s era wheel horses, and the cast iron Kohler engines.  If this Sears tractor had a Kohler, I would have already said yes!  But... It has a 16hp Tecumseh.  I don't even know if there are rebuild kits for this engine.  Are these large Tecumsehs decent engines?  How do they compare to the Kohlers that Wheel Horse was using during the same era?

 

http://www.tractordata.com/lawn-tractors/001/3/9/1398-sears-st16.html

[TravelinJavelin 620]

if its a overhead valve run as fast as you can away from the tecumseh the electrical if bad you'l have to mortgage the farm and also in my humble opinion the torque is not the same compared to the kohler..... tecumseh's you got to rev high to get the same output from half throttle kohler just my experience

[ClassicTractorProfessor 5,455]

I myself have always been a Kohler guy...nothing beats an old K-Series for reliability, ease of repair, or power. Had a couple Tecumseh powered tractors for a while...wasnt impressed and got rid of them. My opinion (along with most people here I'm sure lol) is that the best combination is a Wheel Horse with a Kohler 

[slammer302 2,156]

My experiences with tekys are if they run good they are great but ive not had much luck bringing them back from the dead. 

[Searcher60 209]

I spoke to the owners of two Wheel Horse dealers past week. Senior people in here know them both. One told me that Onan engines run forever and never blow up. He was a very, very, long time, well known, knowledgeable Toro/Wheel Horse dealer in the NE. I also spoke to another very well know dealer in the Mid-Atlantic that has repeatively told me Onan engines are going to  blow up, when is the question.  I had a WH with a vertical shaft Tecky that must have had a gazillion hours on it. I did a valve job and fixed the governor and it was a screamer.  Auto trans, Tecumseh, cut grass and ran great.

 

Asking if a Tecky or Kohler is the best engine is like asking which oil to use. Everybody has an opinion. Kohler engines have the balance shafts/gears which people in here call handgrenades due to the claimed failure rate. Tecumseh's are damn good engines. You can't mow a steep slope with a lot of Kohler's because they do not have pressurized lubrication. Well, Tecumseh and Onan engines do have an oil pump with pressure lube. Onan has both pressure lube and oil filter. Some Tecumseh engines have balance shafts and gears. 

 

My opinion. If you do not have patience, small engine knowledge, and the proper tools, buy a Kohler. The Onan and Tecumseh do not like to be mistreated, rigged with coat hangers and duct tape because their owner is to cheap or ignorant to maintain and repair them properly. I think the old Kohler's may tolerate  incompetant, cheap skate owners more so than the other two. Still, the Kohler balance gears do eventually wear out, and if you cut grass on a slope, you may get into trouble. You can also get into trouble rebuilding a Kohler with the current parts situation. 

 

I would not personally turn down a Wheel Horse because it had a Tecumseh. I like Onan. They are screamers. But, I have 2 Kohlers and 1 Onan. Whatever you buy, spend a few bucks and buy a tachometer and do not let it run low on oil. None of my mowers are oil burners. 

[Tankman 3,523]

The old Kohlers can't be beat! Was skeptical 'bout Onan but my '90 520-8 is a Stallion!

 

Edited October 15, 2017 by Tankman

[Fordiesel69 271]

The big teckys were pretty good inside.  I scored a nice 16HP but the carb was missing and so was the gov linkage.  I never did end up using it, but inspecting the insides it was very well built.  The issue is simple, their carbs are junk.  It made an otherwise good engine very frustrating to operate.  Where I am personally confused, is with all the dealers providing feedback (back in the day) why they never listened and redesigned the carb long before loosing market share and subsequently going out of business.  Im sure there is more to all that but the carbs certainly didn;t help matters.  

Also forgot to mention, some of the cast iron big block teckys used tapered timken bearings instead of the ball bearings that kohler used.  The crank end play was much more important to get right on these so the bearings are properly pre loaded.

 

If you can ever score a complete cast iron bigger 12+hp tecky, do so.  They are cool to have around.

[Maxwell-8 4,368]

16 hours ago, ebinmaine said:

 

As a disclaimer I should note I can't verify the source's information. 

 

@AHS and I were going back n forth and I found some torque output specs for both  Kohler K341 and Tecumseh OHV 160. 

Both were 16 HP at 3600 RPM. 

Kohler torque was stated as 28 + ft lbs. 

Tecumseh torque was stated as 25 + ft lbs. 

 

It's important to note that the Tecumseh OHV 160 is substantially smaller in cubic volume than the Kohler K341

Very interesting! Would love to find a power graph. to see which one has the best torque pickup, and which one holds on the longest.

 

Seems like the Tecky has a spike in torque near the end. while the Kohler just keeps his torque consistent all until the end where it drops off due to the inefficienct flathead design.

 

Quite interesting to see a gas engine making 16hp and 25ft lbs with 27.66ci. While my diesel is making 14hp and 28ft lbs with 31ci. both being OHV. Even though a diesel feels stronger..

 

 

 

 

[Maxwell-8 4,368]

26 minutes ago, ebinmaine said:

The diesel should definitely be stronger.  

The torque output of a diesel is usually much higher than a comparably sized gas engine. 

From the specs I got, not so much relative to the engine capacity, but look at that flat torque curve. peak torque at 1500rpm. and never dropping more then 5ft lbs from that peak.

 

30 minutes ago, ebinmaine said:

I'd be curious to know why you see a spike in the Tecumseh torque curve. 

   Not really a spike but lower torque in the bottom end, and when  revs increase, the OHV design insures good airflow their for high torque at high rpm.

And since hp = TQ x ?5454? x rpm. That will explain the same hp for the big difference in displacement

At 3600rpm these engine are making 19.2 ft lbs.   9 and 6ft lbs from the peak

[Maxwell-8 4,368]

I guess diesels just keep going due to the compression and insanely heavy flywheel but now I am getting  Srry

[Maxwell-8 4,368]

1 minute ago, ebinmaine said:

That's a very cool graph. 

It's not representative to what I was reading the other day though. 

I'm fairly sure I saw the peak torque 1000+RPM higher than the 1500.  

 

Definitely curious to see what the actual verified numbers are.  

 

I'd be pretty impressed to see a PEAK torque output only 300 RPM off idle in a single cylinder gas engine. 

 

My seat of the pants Dyno tells me that 1500 is a VERY low number. 

 

It is they come right from the manual, so they are correct. 

I am thinking the flywheel must be as heavy as a small kohler.

[Maxwell-8 4,368]

4 minutes ago, ebinmaine said:

It's the super high compression of a diesel that's the kicker.   

 

Oh and you feel it too

18,1 to 1 to be exact. 

Edited November 29, 2021 by Maxwell-8