Tecumseh 6 HP Go-Kart - Cold Idle Problem

gn6027 · 06-28-2008, 02:46 PM

On my son's go-kart, it won't idle until its warm. The carb has the primer bulb, and fixed idle & main jets.

It roars to life with a single pull of the rope starter after 4-5 primes.

In order to keep it running, my son sits in the cart, and I start it, and continue to press the primer bulb 15-20 times (to keep pumping gas into the carb) after it starts. He can then feather the gas pedal and after a lap around the yard, it seems to idle fair.

I have a manual, and I've had the carb apart. Sprayed every passage with carb cleaner, and everything appears to be clean.

I've had this problem since I bought the go-kart 3 years ago (I bought it used, and knew it didn't run exactly right).

Today, I had the carb apart again, and cleaned it again, and it still doesn't idle correctly.

I took my can of carb cleaner, and sprayed around the idle jet, the primer bulb, and then the throttle shaft. I found when I sprayed around the felt dust seal, the engine raced.

Could a worn out dust seal cause this sort of cold idle problem?

What else could be causing?

Sorry for rambling on...

Thanks for any help!!

**K-B** · 06-29-2008, 05:40 PM

May be a worn throttle shaft...check for side-to-side play on the throttle shaft.

gn6027 · 06-30-2008, 05:41 PM

K-B,
I think you nailed it!!! It seemed to have some excessive side-to-side play, and when I tore it apart, it had worn by about 0.015 on one side.

I swapped it with a shaft from another carb, and seemed to help. I'll need to try it a couple of more times when the engine is cold to see the real effect.

The hole in the carb was still round, and didn't appear to be worn at all. Looks like there is only about 0.003 running clearance.

Thanks for your help!

06-28-2008, 02:46 PM	#1 (permalink)
gn6027 Registered User Join Date: Jun 2008 Posts: 2 OS: xp	Tecumseh 6 HP Go-Kart - Cold Idle Problem On my son's go-kart, it won't idle until its warm. The carb has the primer bulb, and fixed idle & main jets. It roars to life with a single pull of the rope starter after 4-5 primes. In order to keep it running, my son sits in the cart, and I start it, and continue to press the primer bulb 15-20 times (to keep pumping gas into the carb) after it starts. He can then feather the gas pedal and after a lap around the yard, it seems to idle fair. I have a manual, and I've had the carb apart. Sprayed every passage with carb cleaner, and everything appears to be clean. I've had this problem since I bought the go-kart 3 years ago (I bought it used, and knew it didn't run exactly right). Today, I had the carb apart again, and cleaned it again, and it still doesn't idle correctly. I took my can of carb cleaner, and sprayed around the idle jet, the primer bulb, and then the throttle shaft. I found when I sprayed around the felt dust seal, the engine raced. Could a worn out dust seal cause this sort of cold idle problem? What else could be causing? Sorry for rambling on... Thanks for any help!!

06-29-2008, 05:40 PM	#2 (permalink)
K-B Moderator/Gearhead Join Date: Oct 2005 Location: NY Posts: 2,711 OS: Ubuntu 8.04 My System	Re: Tecumseh 6 HP Go-Kart - Cold Idle Problem May be a worn throttle shaft...check for side-to-side play on the throttle shaft. __________________ Registered Linux User #435503 A peanut sat on the railroad track His heart was all aflutter The five-fifteen came rushing by Toot toot! Peanut butter.

06-30-2008, 05:41 PM	#3 (permalink)
gn6027 Registered User Join Date: Jun 2008 Posts: 2 OS: xp	Re: Tecumseh 6 HP Go-Kart - Cold Idle Problem K-B, I think you nailed it!!! It seemed to have some excessive side-to-side play, and when I tore it apart, it had worn by about 0.015 on one side. I swapped it with a shaft from another carb, and seemed to help. I'll need to try it a couple of more times when the engine is cold to see the real effect. The hole in the carb was still round, and didn't appear to be worn at all. Looks like there is only about 0.003 running clearance. Thanks for your help!