Onan issues

[Forest Road 594]

Is it me or do Onan twins seem to have far more issues than Kohlers? I'm basing this on what I've read here and other sites.

[Kelly 1,028]

yes they do, kinda like a big tecumseh, and if you think about it, I'm sure there is way more Kohler owners here than onan, but I tell you what, when running right Onans are very nice engines, lots of power and smooooooth.

[dryrun 0]

Hello, I've got a couple of pennies in my pocket, so here is 2 cents worth.

I ran onan engines for thirty years on airco welders, generators etc, with very little problems. Always started good and ran smooth with normal maintainence.

About 1968, I started as a mechanic on Davis trenchers, and Melroe Bobcats. I noticed that some times, stationary engines react a lot differently to being used in mobile equipment. This became very evident when Melroe installed PETTERS engines in the Bobcat. The huge flywheel on the engine, and the lack of a strong mounting plate[VIBRATION] did not do well in a machine that does rapid direction changes and is, by design, used in rough terrain. The ONAN powered units seemed to do pretty well, but were phased out in the horsepower race. DAVIS [mini sneakers] used the ONANS with very little problems.

I guess what I'm saying here , is that different experiences, different conditions make the world go around. I personally like the CCK/CCKA engines, and was disappointed to see the end of the era.

What I have said here is strictly my personal opinion.

REGARDS,GEORGE

[Horse Fanatic 49]

I think they are superb engines but are less tolerant to neglect.

[SAM58 30]

Is it me or do Onan twins seem to have far more issues than Kohlers? I'm basing this on what I've read here and other sites.

Ever notice that the Onan Twins seem to let go on the back cylinder, could be a heat problem.

I had a Onan 18 HP on a Sears and the same thing...

back cylinder broke a rod, destroyed the block.

2 cents. :wh:

[300zx 7]

It does seem like the single cylinder Kohler's are pretty bullet proof and have served me well over the last 25 years, but I really like the smoothness of the twin cylinder engines. I have a twin Kohler on my ZTR and the twin Onans on the 520's. The twin Kohler is only 3 years old and hasn't caused me any trouble so far. I have gotten to the point on the older twin Onans that every time I buy one, I pull the engine, tear down the top to soak and rebuild the carb, clean all of the air fins, take the carbon out of the head and on the pistons, lap and reset the valves and install new plugs. I also pull the pan to clean out the gunk. I check to make sure the coil and ignition module are good and then bench run the motor. I've not picked up an Onan yet that ran right without this process. I never went this far on the old single cylinder Kohlers unless there was a major problem. As much as I like the twin cylinders, I do think they take more maintenance. Whether the twin Kohler will be the same way when it gets as old as the Onan's, I don't know yet. I have to admit, though, I have never met an engine I didn't like!!!! It is just that some are more finicky that others.

[sorekiwi 761]

I have to admit, though, I have never met an engine I didn't like!!!! It is just that some are more finicky that others.

You obviously havent owned a Tecumseh yet!! :thumbs:

[300zx 7]

You obviously havent owned a Tecumseh yet!!

No, I am afraid I do. My Horse Troybilt is a Tecumseh. Every other year, I soak and clean the carb to keep it from surging.

[IDriveWheelHorse 0]

Well I have owned a K301 on a C-145 for about three weeks now and when it runs (albeit the carb needs a rebuild) it runs solid.

I am very familiar with the KT17 (grew up around it) and believe that its a really good engine, and just like its single cylinder sisters, it can take a beating with little or no retaliation. By far I think the KT17, KT19, and KT21 sound BEASTLY when they are running (Almost like a Harley at idle), but I think thats just because of the exhaust system; 3 foot long pipe with a large muffler and tapered exhaust out.

As for the Onan twins.. I just purchased a 416-8, 600Hrs... and I do love the way it runs. Very smooth and doesn't skip a beat. However, I feel a carb rebuild very very soon due to the surging at idle and the need for constant 1/4 pull of choke to run correctly. As for the way it sounds, it sounds similar to a Kohler twin, only with the muffler right at the heads (weaker exhaust thunder, as I like to call it)

So give me about a year and ask this again... I bet I can already tell you which one will be "repaired" more. I'm sorry, I mean to say "Maintained more" haha.