Tecumseh runs good until it gets warm need advise

[myjunk]

I have a Tecumseh 3.5 engine that runs good until it gets run for about 10 to 15 minutes then it quits. I'm guessing weak coil or condenser or maybe even put new points in it. Has anyone else had a similar problem. Thanks for your help.

 

[f4radar]

Does it start back up after it dies? Tried a new spark plug?

 

[Triley41395]

I'd try changing the plug first. Had one on a car once that had cracked ceramic and would start missing after a few minutes. You could take it from another bike for testing and it wouldn't cost you anything.

 

[Triley41395]

Does it start back up after it dies? Tried a new spark plug?

Dammit, you beat me to it.

 

[canuk]

will it restart after it cools down,check your valve lash I have found exh with no clearance would start great but would quit when it got hot and would not restart until it cooled down.Found that after changing points condensor plug coil

 

[myjunk]

will it restart after it cools down,check your valve lash I have found exh with no clearance would start great but would quit when it got hot and would not restart until it cooled down.Found that after changing points condensor plug coil

Yes, it will start after it cools down. It will not start until it cools down. I have the engine in a small gokart that my grandsons drive and they said it made a popping sound.

 

[myjunk]

Dammit, you beat me to it.

I'd try changing the plug first. Had one on a car once that had cracked ceramic and would start missing after a few minutes. You could take it from another bike for testing and it wouldn't cost you anything.

What would be the correct plug for this engine?

 

[Triley41395]

What would be the correct plug for this engine?

Don't know for sure but this is what I use.

 

[creia]

What would be the correct plug for this engine?

Champion CJ8 or (better, and my preference) NGK BM6A
Michael

 

[Thepaetsguy]

It never hurts to check the plug gap either I have found some wild variation. I’ll stand behind nos bare label J8 spark plugs but there tall and not for MOST mini frames if I had to guess. not to mention 1 pack of four is over $200 last I checked.

 

[Harquebus]

No one should be paying $50 per plug, that's lunacy.

What would be the correct plug for this engine?

Champion CJ8 or (better, and my preference) NGK BM6A
Michael

I don't know much about Tecumsehs but I am guessing 3.5 HP means it is a flathead. If you look at your old plug and note its thread reach, you can basically tell by looking which ones will fit. They have a shallow reach into the combustion chamber compared to an OHV spark plug. *According to the link below the reach should be 9.5mm.

Must be hundreds of suitable plugs. This cross reference site may shed some light on the subject (the link shows a search of plugs comparable to Champion RJ19LM): Sparkplug Cross-reference

Of course you have to do independent research on each one to find out the heat range and materials they're made of (copper, platinum, iridium).