Exhaust Glowing!!!!

[Shuboxlover 481]

Tractor (C-160 auto) is new to me....

Rebuilt the carb, seems to run o.k. but smells a little gassy??

When I took it out for its maiden voyage, when I had the throttle wide open, I could see the muffler and elbow right above the muffler was glowing orange. It was dark outside and I don't have the hood on it yet, so mo lights either.

Is this normal, if not, what is causing it and how can I fix it?

Thanks

[TT-(Moderator) 1,162]

It's not uncommon to get the glow at the elbow, and I've had a few "good runners" that would turn the muffler red too.

Providing the carb mounting gasket(s) are in good condition and sealing properly, I would recommend checking the gap on the points next (should be .020") and it might not hurt to check the valve clearance - depending on what you find with the point gap.

All instructions are in the Kohler manual.

[Shuboxlover 481]

I put new carb mounting gaskets on when I rebuilt the carb, so those should be good.

Is it a pain to do the stuff you mentioned?

[TT-(Moderator) 1,162]

Points? They aren't bad.

Valve adjustment is a little more involved and the carb will need removed.

Check the points first though.

[rmaynard 16,301]

I agree with TT.

If you've had the engine apart, the valve clearance may be off.

I haven't done an engine rebuild in years, but I remember reading that the compression release uses the exhaust valve in Kohler engines. If the valve adjustment is off, the compression release does not function correctly causing overheating at the exhaust.

Bob

[Shuboxlover 481]

How involved is this, are we talking about getting inside of the crankcase, or is this stuff that can be accessed from the outside by take a few things off like the carb and such?

I haven't had the engine totally apart, I separated the engine from the oil pan to put a new gasket in, would that affect anything inside the crankcase?

The ACR thing seems a bit intriguing, sometimes when I crank it over, it kind of "sneezes", kicks back a bit, then continues to turn over and start

[gwgdog66 23]

Well I had a reply all typed up and it went poof. where it went??

I'd start with the point gap, as others have stated.

If you need to adjust the valves it is fairly simple, and can be done by removing the carb and crank case breather located right below the carb. The service manual explains it in good detail.

[Buzz 502]

I've heard that a carburetor running too lean could cause the exhaust to glow also. I don't remember where I heard it, maybe from the voices in my head..... :thumbs:

[tbbahner 28]

All posts are good things to check. My past experience with the muffler glowing is usually the timing is off. Had one that I'm supprised the muffler didn't melt down.

Adjusted timing and problem went away.

Tom B

[sgtsampay 117]

How would you ajust the timing? I know of one person who had a glowing snowblower 9HP tec that always ran a little wierd and has a glowing muffler. Thanks.

[TT-(Moderator) 1,162]

The ignition timing on this particular Kohler is adjusted by increasing or decreasing the point gap.

Some Tecumsehs have slotted holes in the coil mounting bracket to allow it to be turned a few degrees in either direction.

[sgtsampay 117]

oh, thats it? I thought it would be more involved, like with the crank shaft or something.

[Shuboxlover 481]

I did adjust the points gap (to .020" ) I think it may have been a bit to wide! I had it out one time in the dark after adjusting the points and didn't see the muffler glowing...but we'll see. :thumbs:

[rickv1957 75]

Wider gap advances timing,Rick

[Docwheelhorse 2,740]

I thought that when it starts glowing you hit the oxygen

Oh yah.... thats the acetylene torch you do that too!!!

Tony

[Shuboxlover 481]

So..................would an advanced timing cause the exhaust to glow, or would you expect that retarded timing would make the exhaust glow?

[junkman 0]

running at WOT for extendre time will do it too, :D

[rick 257]

The often quoted .020 point gap is a starting place to get the motor running. The flywheel has two timing marks stamped in it, "T" for top dead center, and "S" for spark timing.

The spark plug should fire before top dead center.

I have used a real simple method for more than forty years, you only need a multimeter or test light and power source.

Remove the spark plug, turn the engine in a clockwise direction at the flywheel by hand until you feel the air start to come out of the spark plug hole,indicating the piston is rising on the compression stroke.

There is a hole in the aluminum plate that the blower housing bolts to, find it and you will be looking at the rim of the the flywheel next to the starter ring gear.

Look carefully as you slowly turn the flywheel by hand in a clockwise direction.

You are looking for the "S" mark stamped in flywheel. The letters may be obscured by rust or dirt, so do what you have to see them.

When you get the "S" centered in the view hole on the compression stroke, you want to be sure the points are closed, with the adjustment lock screw snug, but not so tight that you can't adjust the point gap.

If you are using a multimeter, use the ohms or continuity function, clip one lead to the part of the points that fastens to the engine, and the other to the moving arm of the points. At this point, the meter should indicate a complete circuit.

[rick 257]

If you are using a test light with battery ignition, clip the lead to the movable

arm of the points, and stick the probe part where it will ground. Turn the ignition

key On. The test light should glow with the points closed.

If you have magneto ignition, clip the test light lead to the movable arm of the points as before, and stick the probe in the + connection at the battery. The test light should glow with the points closed.

When everything is set up, indicating a closed circuit at the points; test light glowing or meter indicating continuity: slowly open the points until the circuit is broken.

Tighten the locking screw for the point adjustment. I always turn the flywheel around again with everything still set up, sometimes tightening the screw will move the adjustment a little.

When the circuit breaks as "S" centers in the hole, you are done. You have timed the points as Kohler intended.

Some glow at the exhaust is normal, excessive glow can be caused by retarded timing(we just took care of that, didn't we?), a leaking exhaust valve, a lean fuel mixture, or using too high octane fuel. There is an excellent thread on fuel in the forum, if you haven't read it.

[Shuboxlover 481]

That's a great explanation....thank-you.

Mine seems to be running great now, but I'm gonna do this just for s**** and giggles :D

[rick 257]

You are welcome!