Minimum RPM for Kohler engine to "idle" at safely

[Alrashid2 361]

Hey guys. I know it's been stated here multiple times that the Kohler K series engines should not be left to idle for long like modern engines are able to, and that they are designed to be run at full throttle.

 

However, I am just curious at what RPM you would consider high enough past idle (1200 RPM) to allow the engine to sit at for 5-10 minutes if you arent going to just shut her off and back on. 

 

I was playing around with the idea of setting the idle screw on my carb high, so that I cannot idle it as low as 1200 RPM - that way, when I press the throttle all the way down and do for whatever reason need to let it idle for a bit to cool off or just be quiet (moving a lot of firewood at night lately), it'll still be high enough to be safe for the old Kohler.

 

I currently have my idle adjustment screw set at 1750 RPM. Runs slow enough to be much quieter but fast enough that it audibly sounds faster than idle and is hopefully safe to allow it to oil and cool properly still. 

Just curious of your opinions. Thanks all!

[rmaynard 15,806]

Kohler says that engines with "slinger" oilers need to idle between 1100-1200 rpm. Does not state how long.

[ebinmaine 69,748]

IMHO 2200 to 2400 is a minimum. 

 

1200 is the idle SETTING  but there is widespread common knowledge that an air cooled engine should NOT be left to idle. 

 

 

I'd be very curious to see actual factory wording.  

 

 

 

[ri702bill 8,761]

20 minutes ago, rmaynard said:

Kohler says that engines with "slinger" oilers need to idle between 1100-1200 rpm. Does not state how long.

Idle until the big "POP" and oil puddle happens...

[pfrederi 18,195]

Some K series for generators were governed at 1800 rpm.

 

 

[clueless 3,075]

5 to 10 minutes  maybe around 3400 rpms, why take a chance? A little more fuel is a lot less expensive than the "POP and PUDDLE" . Kohler says after 1200 rpm the oil is supposedly coating everything, at that point it's about the heat, less rpm more heat that's probably why they say it should be run at WOT, they don't really specify if that's under load or just idling. If you really need to let it idle that long I wouldn't set below 2200rpms,JMHO,

Edited Thursday at 01:57 AM by clueless

[ebinmaine 69,748]

1 minute ago, clueless said:

5 to 10 minutes  maybe around 3400 rpms, why take a chance? I little more fuel

 

 

Or why not just shut it off completely?

@Alrashid2

 

Is there a particular specific reason to leave it running?

[Handy Don 13,087]

1 minute ago, ebinmaine said:

Is there a particular specific reason to leave it running?

I've had to train myself to shut down for pauses longer than a minute.

For many years I was exclusively using recoil starters and it took awhile to take advantage of ‘lectricity!

[pfrederi 18,195]

Lately overheating at idle has not been an issue at all

[ri702bill 8,761]

27 minutes ago, Handy Don said:

and it took awhile to take advantage of ‘lectricity!

Did you finally warm up to indoor plumbin' too ???

[SylvanLakeWH 26,599]

Only two speeds on my 10 hp K 241:

 

1. WOT

2. Low idle for 5-10 seconds before I shut it off...

 

Now, on my A-65  there's only one speed... on...

 

, (which actually come to think of it, due to inflation and Executive Orders, now needs to be "my two nickels..." Mods do we have an emoji for that??? 

 

 

[kpinnc 13,125]

3 hours ago, ebinmaine said:

IMHO 2200 to 2400 is a minimum. 

 

[Ed Kennell 39,770]

2 hours ago, ri702bill said:

Did you finally warm up to indoor plumbin' too ???

Probably not.    Some still use clutches, stick shifts, and blowers w/o cabs.  

[ebinmaine 69,748]

1 minute ago, Ed Kennell said:

Probably not.    Some still use clutches, stick shifts, and blowers w/o cabs.  

 

 

You modern guys with your fully enclosed People Protection Systems...

 

 

[SylvanLakeWH 26,599]

7 minutes ago, Ed Kennell said:

Some still use clutches, stick shifts, and blowers w/o cabs.  

Hey hey hey... 

 

I represent that...!

[Alrashid2 361]

4 hours ago, pfrederi said:

Lately overheating at idle has not been an issue at all

That was my thought too haha. I'd be less prone to idling in the summertime.

[ri702bill 8,761]

1 hour ago, SylvanLakeWH said:

Hey hey hey... 

 

I represent that...!

[Alrashid2 361]

Reason I was asking is I'm finding that I'm shutting her on and off every few minutes and it seems to be tolling on the battery. Also when I'm not letting her run continuously, I don't think she's warming up fully and I'm finding a ton of condensation on the dipstick. It's even frozen solid on a cold start! Like frost on an ice cream package 

[Marv 954]

5 hours ago, ebinmaine said:

You modern guys with your fully enclosed People Protection Systems..

for some of us who are cold in the house at 75 degrees, a warm cab is great while moving snow.

Marv

[SylvanLakeWH 26,599]

9 minutes ago, Alrashid2 said:

Reason I was asking is I'm finding that I'm shutting her on and off every few minutes and it seems to be tolling on the battery. Also when I'm not letting her run continuously, I don't think she's warming up fully and I'm finding a ton of condensation on the dipstick. It's even frozen solid on a cold start! Like frost on an ice cream package 

let it run, full throttle...

 

[clueless 3,075]

41 minutes ago, Alrashid2 said:

Reason I was asking is I'm finding that I'm shutting her on and off every few minutes and it seems to be tolling on the battery. Also when I'm not letting her run continuously, I don't think she's warming up fully and I'm finding a ton of condensation on the dipstick. It's even frozen solid on a cold start! Like frost on an ice cream package 

I think the question is why do you feel the need to shut it off every few minutes? Why not let it run.

[Alrashid2 361]

Ha many on this thread have recommended shutting her off...

 

Definitely a split discussion it seems!

[clueless 3,075]

9 minutes ago, Alrashid2 said:

Ha many on this thread have recommended shutting her off...

 

Definitely a split discussion it seems!

Many? you do you my man.

 

[Alrashid2 361]

Ha just thought it was an interesting discussion. These Kohlers are the only engines I've ever heard such adamant opinions on when it comes to idling and such. Every other small engine (air cooled and oil slung) I've always just heard people running however they want to, so find it interesting.

 

Would love to do an experiment at some point and collect some data. It seems that even at idle of 1200 RPM, the Kohler is able to lubricate efficiently. The issue seems to be the lack of cooling. I'd have to do some research and see if I can find a peak operating temperature and find out at what minimum RPM the engine is able to cool at or below that temperature... would be fun!

[ebinmaine 69,748]

27 minutes ago, Alrashid2 said:

Ha just thought it was an interesting discussion. These Kohlers are the only engines I've ever heard such adamant opinions on when it comes to idling and such. Every other small engine (air cooled and oil slung) I've always just heard people running however they want to, so find it interesting.

 

Would love to do an experiment at some point and collect some data. It seems that even at idle of 1200 RPM, the Kohler is able to lubricate efficiently. The issue seems to be the lack of cooling. I'd have to do some research and see if I can find a peak operating temperature and find out at what minimum RPM the engine is able to cool at or below that temperature... would be fun!

 

 

A couple points here.

 

A. To the best of my knowledge, ALL small engines that are air-cooled and splash lubed have near identical RPM requirements to a Kohler.

 

B. I would be far less concerned about the cooling at 1,200 RPM then I would be the oil splash lubrication.

There was a thread on here at one point where someone took some readings on different RPMs and different operating time periods.

Look at it this way. Your engine still needs oil whether it's turning 1,200 times per minute or 3,600 times per minute.

At the higher RPM it obviously would need more flow... But I would feel much better leaving it well above idle RPM where you can feed the maximum amount of lubrication to it.

 

As stated by @pfrederi above, there are generator engines regulated at 1800 RPM.

I personally would consider that the absolute bare minimum non-negotiable lowest point I would possibly leave an engine for an extended amount of time..