Kohler Will Not Throttle Up

[MalMac 1,332]

Ok, got a K321 here that will start only on a idle. When started it runs smooth as silk, go to throttle it up it will hack, cough, spit shake. Give it more throttle and just dies. When running at idle you put any pull on the motor it will kill it. Took carb apart it’s nice a clean. Starting to think electrical. Any ideas out there. I did put a new condenser on it awhile back at beginning of summer. That doesn’t always mean anything though. 

[ebinmaine 70,719]

My gut tells me I would start with cleaning the carburetor even though you just stated it it's clean...

 

 

After that, electrical.

 

[Pullstart 64,525]

It wouldn’t hurt to check the points condition and gap if it’s a points ignition, they are crucial for smooth operation.  It’s crazy what symptoms arise when they are dirty or the gap is off..

[hotajax 226]

I am with Ebinmaine on this one.  If ignition is your issue, it will run crappy at most rpm's.  My friend, I seriously think you should remove the carb ( easy ), remove the bowl, and check:  1.  For crap in in the fuel passages;  2.  An overly stiff diaphragm.  I'm betting this is a fuel issue.  Now, here's another issue that has burned me twice:  crap obstructing fuel flow from the tank to the fuel line.  Drain your fuel, and remove the fuel line and the little filter that sticks upwards into the bottom of the tank.  If your design is like mine, you just pull hard through the grommet.  Good luck, let me know how you make out.  Yes, it's frustrating, but it sounds like a moderately easy problem to fix.  

Edited November 4, 2019 by hotajax
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[gwest_ca-(File Mod) 11,243]

A condenser will do exactly that and easier to try.

 

Garry

[wallfish 17,490]

5 minutes ago, gwest_ca said:

A condenser will do exactly that and easier to try.

 

Garry

I'm betting on condenser

[hotajax 226]

We need to place bets on this and make it interesting.  

[The Tuul Crib 7,338]

1 hour ago, pullstart said:

It wouldn’t hurt to check the points condition and gap if it’s a points ignition, they are crucial for smooth operation.  It’s crazy what symptoms arise when they are dirty or the gap is off..

[MalMac 1,332]

Thanks guys, I messed with it a little more.  Got no where. I’ll try a few more things in the days to come. I’ll report back on what I find. Thanks again for all the suggestions.

[wallfish 17,490]

2 hours ago, hotajax said:

We need to place bets on this and make it interesting.  

$25 on condenser (bad condenser, not grounded, bad wire on it, connected to the positive side of the coil, ect. ect.)

A bad plug wire could also give those same symptoms

[953 nut 57,889]

Gapping the ignition points at .020 has always been the standard answer to how points should be set. That probably will get you into the ballpark where the engine will run, but with a bit of additional effort you can improve the engine’s power and performance.

The Kohler engine manual in the Red Square files section covers two methods for setting the ignition timing, Static Timing and using a Timing Light. This manual is a relatively new manual and it overlooks the fact that many of our engines were built prior to the ACR (automatic compression release) camshaft.

Earlier engines (mostly 1965 and earlier) had a Spark Advance camshaft that can not be timed using Static timing. At rest (and very low RPMs) the timing is retarded to fire slightly after TDC. The timing mark (SP) on your flywheel is at twenty degrees before top dead center but at rest the points on these engines break about ten degrees after top dead center. The only reliable way to check or set the timing on these engines is with a timing light.

There are a couple ways to determine what camshaft you have. Presuming the camshaft in your engine is the one it was born with the data plate on the engine has a suffix that can tell you what camshaft was used. The table below will tell you the suffix applicable to your engine. The other way to determine what camshaft you have is to remove the cam gear cover and take a look. If you see a mechanism attached to the cam gear it is the ACR cam.

 

 

The following engines have the spark advance camshaft;

K-141, Suffix prior to “C”

K-161, Suffix prior to “J”

K-181, Suffix prior to “D”

K-241, Suffix prior to “D”

[hotajax 226]

5 hours ago, wallfish said:

$25 on condenser (bad condenser, not grounded, bad wire on it, connected to the positive side of the coil, ect. ect.)

A bad plug wire could also give those same symptoms

So, you wanna go 25 on a condensor and it's wiring?  

[wallfish 17,490]

5 hours ago, hotajax said:

So, you wanna go 25 on a condensor and it's wiring?  

Yes. And you're going carb clean/fuel?

[wallfish 17,490]

The fuel shut off will also allow the engine to start for a short period when the bowl is low and it will only idle. Eventually stopping all together. Just making it interesting 

[hotajax 226]

On 11/5/2019 at 6:06 AM, wallfish said:

Yes. And you're going carb clean/fuel?

I'll go with a fuel issue.  Carb, bad fuel filter in the tank, anything through which gasoline passes, fuel line. 

[MalMac 1,332]

The culprit 

[tunahead72 2,518]

Wow, that's your "new" condenser?

 

[MalMac 1,332]

Yep sure is. I went to take it off and the wire just fell off. There’s some quality right there I’ll tell ya. 🤬

[pacer 3,175]

 

 

I can feel your frustration!!

Was working on a B43 Onan with a weird problem - on/off starting prob, on/off running erratic, etc. Usually seeming mostly a carb problem and had been in/out of carb so many times it almost came apart when I removed itHad also been thru all ignition components about 3-4 times and also all the fuel delivery syst about that many I consider myself a pretty good 'shade tree mechanic' having been some 60+ yrs fooling with engines large and small, but I was almost ready to do an engine swap when I thought I would do ONE more 'go thru' Luckily? I started with another ignition ck and removed the points/condenser.... still looked just like the last time I looked at them .... but, on reinstall; I thought I saw a suspicious spot on the condenser, Pulled it back out and looked at closely .... hmmmm what is that tiny crack in the insulation? Kinda bent the wire and WHOA!! theres where the magic 'juice' was going. Was mounted really close to a bolt head that had all the engine heat and it had hardened the insulation and made it brittle and cracking allowing the magic to escape!!

 

Quickly scrounged around and found another condenser, mounted it and HOORAY!! thing ran like a top

 

[wallfish 17,490]

4 hours ago, hotajax said:

I'll go with a fuel issue.  Carb, bad fuel filter in the tank, anything through which gasoline passes, fuel line. 

That's $25 worth of fun right there!

I'll PM my address or paypal email