Thread: Glowing, red hot headers

I have a Kohler as well, wrapped the same as you guys BUT, no glowing.

Now, the only reason a header on any motor would glow red is because it's running lean. I'm going to ASSume it's time to have the carbs rebuilt or cleaned on both machines.

Again, I could be wrong here as I'm going off my years of racing cars and that my TM is fairly new and doesn't glow.

Originally Posted by brian3180

Jose, what are other signs of a bad carburetor?

Brian,

To be honest, I'm not a carb guy, I've always delt with fuel injection so Carb's arent my specialty. That being said, some signs of a lean motor wouldnt happen hile it's running, the motor running lean(glowing headers) is a sign of too little oil or a bad fuel mixture. Some signs will be on immediate startup or running at WOT(wide open throttle). Pull the spark plug and look at the tip.

Now, working on carbs isn't exactly the easiest thing in the world and if you have no mechanical experience, I would stay away from it. I believe your local TM repair guys might be able to help, if not, a small motor repair shop might be able to help. Shouldn't be an expensive fix either, if you've never had your carbs rebuilt or cleaned, I would suggest doing it anyway. The carb on these motors are like the lungs, it's quite possible to damage your motor if the carbs aren't in tip top shape.

This is just my humble opinion Brian, again, I'm going completely off my experience with drag racing and building motors. Make a couple of calls to some small engine repair shops(Lawn mowers, go karts), heck, give Kohler a ring and see what they say, hopefully I'm completely wrong and this is a normal thing.

Let us know!

Jose is right, pull the plugs and look at the condition of the plugs. If they have white ash deposits its running lean. Two Main reasons the headers will glow are incorrect timing and lean mixture. Couple things you can also try. Pull the choke out a little before it stalls and stays running and see if the glow goes away or lessens. Or when you see the glow turn the engine off. Wait 1-2 minutes and start it back up. A lean mixture will experience a knock. How old is this engine? Newer Kohlers have a fixed main jet and no adjustment is possible.

Jose over advanced timing is a factor too. Kohler has a 10 BTDC with standard mower engines. on their industiral line its more like 14 BTDC.
If you get stuck with a non-adjustable carb. theres always Ebay. Walbro or Keihin is your best bet.

I would also get rid of the exhaust wrap. Your trapping the heat on the header. It needs to disipate naturally. 08, it has a fixed main jet. Have changed the fuel filter? Try that also. Also, try and report back with what the plugs look like. That your birds eye view of whats going on inside.

Originally Posted by Ara Klujian

Jose is right, pull the plugs and look at the condition of the plugs. If they have white ash deposits its running lean. Two Main reasons the headers will glow are incorrect timing and lean mixture.

Originally Posted by NuTech Carpet Care

Jose over advanced timing is a factor too. Kohler has a 10 BTDC with standard mower engines. on their industiral line its more like 14 BTDC.
If you get stuck with a non-adjustable carb. theres always Ebay. Walbro or Keihin is your best bet.

Awesome, I figured it was the same theorm.

Originally Posted by brian3180

I know that when I shut it off, the motor pops at the end of the cycle. I would not compare the pop to a back fire or anything incredibly loud.

There's your indication Brian. A motor running lean will run normal during operation, but will have an issue upon starting or running WOT(running your machine at maximum rpms).

When Ara says you have a fixed main jet, basically means you can't adjust the mixture. I would do what ara suggests and to check out your fuel filter, that might just be a quick fix and one of the first things I would check. If the filter is dirty, it could throw everything out of whack(main reason why I never liked carbs, too much fine tuning).

Definetly get that spark plug off and snap a picture or tell us what the tip looks like.

Originally Posted by Ara Klujian

I would also get rid of the exhaust wrap. Your trapping the heat on the header. It needs to disipate naturally. 08, it has a fixed main jet. Have changed the fuel filter? Try that also. Also, try and report back with what the plugs look like. That your birds eye view of whats going on inside.

Ara, I have my exhaust and h/x wrapped because my chem-tex kitty 13 doesn't produce the heat I enjoy. Do you think I might be doing more damage than good?

Thankfully, I don't run lean, atleast not yet, but every month or so I'll spray some carb cleaner at the end of the day.

Looks a little white but not too bad . Cant really tell from the picture. Also, is that the number one plug?

I have a spitfire 4.0 and the headers glow red and have done so for a while now. I only started to notice this after the exhaust wrap came off. Pretty sure the manifold can handle this. I am interested if anyone has seen the manifold fail because of this?