Sawmill Engine Overheating

Billbob · January 18, 2014, 06:08:24 PM

The engine on my Woodland mill started overheating today. I was cutting a large 24" poplar. After slabbing off several 1 inch boards to get a good cant I started slabbing 2 inch planks. The engine would overheat and shutdown. After 5 or 10 minutes of cool down it would start up work for a while then start with the shenanigans again. It's a Kohler Command Pro 9.5hp. It has a low oil shutdown feature. I checked the oil and that's ok. I'll check the air filter tomorrow. Any ideas? By the way I ran the mill for a good 5 hours after which the problems started.

The tab for reading the measuring ruler only reached the 4/4 cut numbers and not the regular 1 inch numbers on the left side of the ruler. So I made this attachment out of plexiglass.

POSTON WIDEHEAD · January 18, 2014, 06:10:44 PM

I don't know Bob.....but I hope you get it fixed. Someone on here can surely help.

thecfarm · January 18, 2014, 06:12:48 PM

Good idea with the extension.
I was thinking,

how do you know it was over heating?

WellandportRob · January 18, 2014, 06:18:41 PM

How many blade changes did you do in that 5 hrs of milling. I think 5 hrs straight might be a little much for a 9.5.

Ga Mtn Man · January 18, 2014, 06:19:03 PM

Oil cooler?

Andy White · January 18, 2014, 06:26:49 PM

Billbob
Do you have the shutter on the aircleaner set to summer, or winter operation? Don't know if your mill has that or not, but mine must be set in the right position, or it will not run as it should. It makes a big difference on mine. Andy

POSTON WIDEHEAD · January 18, 2014, 06:26:51 PM

The more I think about it Bob......there's nothing wrong with your engine.
But I really think a log that big is a little bit much for a 9.5 HP motor.
Your engine is just over heating.

Ianab · January 18, 2014, 06:45:43 PM

Is it overheating, or starving of fuel?

Something like a faulty tank vent can cause those symptoms. You get a vacuum in the tank, the engine quits. 10 min later enough air has leaked into the tank to let the engine start again. Repeat the cycle.

While it's a small engine, it should be able to chug away all day making it's 9 hp. Looking at the background in the pictures I don't think the weather is hot enough to cause an issue :D

Although, could the carb be icing up? Similar symptoms, after 10 mins the ice melts and you can restart. That shutter around the air cleaner that Andy mentions is to overcome this. In winter you pull air from near the motor, so it's warmer. In summer you move the shutter and get cooler air from the outside.

Ian

dgdrls · January 18, 2014, 07:04:36 PM

That little motor should cut all day, I'm sure your not at full load for extended periods

How old is the mill, Lots of logs sawn??
Perhaps the motor air cooling tin is clogged with sawdust and restricting air circulation around the cylinder?
An Oil change wouldn't hurt with nice synthetic stuff.

As Ian indicated I would check the Fuel vent also.

Let us know,

DGDrls

hamish · January 18, 2014, 07:25:47 PM

What position is your air cleaner in? The CH270 will run all day so long as you keep feeding it fuel. Does the HM126 have any safety switches tied into the oil alert/on-off of the engine?

thecfarm · January 18, 2014, 07:27:43 PM

And that is a manual mill.That blade is not in the wood steady. Unless you have about 4-5 men with you too. and all 4-5 men know exactly what to do.

dgdrls · January 18, 2014, 07:43:07 PM

Looking on-line Kohler notes there is a fuel water trap?

DGDrls

SawyerBrown · January 18, 2014, 07:59:00 PM

If it really is overheating I'm betting it's not getting enough air -- air filter plugged?

Billbob · January 18, 2014, 08:11:01 PM

I'll reply to all in point form.

1. Didn't realize that air cleaner had a 'position'! I'll check that in the morning and will blow out the filter and housing with air. (cheeks turning red)

2. There are no safety switches to the oil. No oil alert function only 'shut down' on low oil. Checked oil. All OK. Oil looks clean but I will do an oil change tomorrow.

3. Previous owner told me that the mill had 60 hours on it. It's a 2012 model which he purchased from the dealer. I put another 20 hours on it. I'm also going to put on an hour meter.

4. Now that you guys mention it, it was acting and sounding like it's starving for fuel. ie. air lock. I thought it was overheating because it was a long hard cut in the middle especially with a very large knot where there was a crotch on the tree. I was really taking my time making the cut. I'll check the fuel cap tomorrow as well.

5. The carb would't be icing up today. It was +5c. Perfect weather for sawing.

6. I put on a sharpened blade for this log. Blade was working great until it hit that knot. Caused it to wave up. The knot was hard as concrete. Once through the other side the blade continued to cut good.

7. I cut a 24"x12'6" tamarack long yesterday. No problems then.

8. I'll check into the fuel water trap.

8. Yep, TheCFarm, I'm glad the mill came with the extension because some of my logs are cut 12'6". Just barely fit on the mill. I have the material in the shed to make another 8 foot extension. That will give me the log capability of 18'6". That way I can load a log and not be squeezed for space. I don't anticipate needing to saw over 12'6" but you never know what the future will bring. And no to the 'extra help' I was working alone today.

Once again Gents, thank you for the help. I'm leaning toward the problem being fuel ventilation and air cleaner. I'll let you all know tomorrow night how I made out.

Those big logs sure put out the lumber! That log gave me six 2x6, six 2x4, four 1x10 boards and a 1x12 board. I'll get that shed built yet!

bandmiller2 · January 18, 2014, 08:11:20 PM

Billbob, a couple of things to check, mayby mice have built winter quarters in the air cowling. Also you mentioned you need to use the choke to start even if warm,the carb. could be set lean that would tend to make it run hot and reduce its HP. No way in NB this time of year you should be overheating. Frank C.

Billbob · January 18, 2014, 08:15:33 PM

You're right Frank. Shouldn't be an overheat problem this time of year! The mill manufacturer noted that it is normal to have to choke a warm engine to start it. But I will take the air hose to the engine tomorrow and give it a good cleaning.

Bill S

Billbob · January 20, 2014, 08:27:18 AM

Did an oil change on the engine. Checked the air filter which clean as the day it was put on. Blew the dust off the filter's pre-breather foam cover. Put the filter cover on winter operation. Cleaned out the water trap bowl on the carb. Blew out the gas cap with air. When I put it back on I backed it off just a hair. Used the mill for 3 hours. The engine worked fine. I think that I may have been cranking the gas cap on too tight.

SawyerBrown · January 20, 2014, 09:55:54 AM

Quote from: Billbob on January 20, 2014, 08:27:18 AM
I think that I may have been cranking the gas cap on too tight.

say_what

Billbob · January 20, 2014, 11:04:58 AM

According to your signature message SawyerBrown, I'm really tough!! :D

Ianab · January 20, 2014, 02:23:35 PM

We had an old Honda ATV at the farm like that. Dodgy vent in the filler gap. When it was done up tight it didn't vent. Back it off 1/8" from the stop and it was fine. Same symptoms, you could ride about a mile and it stopped. Open the tank to check if it had gas, and you could ride another mile.

Might be the same with the mill engine?

Ian

Billbob · January 20, 2014, 04:41:08 PM

That's what I'm thinking Ian. Seems to be working fine now.

Bill

diesel pap · January 20, 2014, 07:55:57 PM

i had a honda atv start dying about 2 weeks ago. i pulled the vent hose up out of the forks and sure enough it was plugged. glad you found your problem.