Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

2-Cycle TEC engine surging  and as it gets hotter the engine eventually dies after 10 minutes of running. I checked and cleaned everything.  Carb is spotless, changed ignition coil, exhaust ports & exhaust spotless, new sparkplug.  I did notice a bit of oily drops around the middle of the block. The compression seems to be ok when pulling the pull cord.

The cap's vent hole was clear and I did put a used carb but I cleaned it before installing. I did change the spark plug and I made sure it was gaped at .25 the engine is running much much better with the new plug. The plug I removed had a .35 gap I don't know how the old plug had such a large gap I always gap all plugs before installing new or used.

I believe the spark plug gap is supposed to be .030" so a gap of . 035 isn't all that wild and likely had no effect on how the engine ran.  Maybe the old plug was bad? 

Just a guess at this point,  The enige is running lean (surging).... If the carb is clean,  you may have a case leak or a bad seal around the crank...

   Start looking for bubbles (very small) around seals and gaskets while the engine is running... if you son't see any,  try spraying a mild dish soap solutionaround the seals and gaskets before the engine gets too hot...

The bubbles may appear small,  but you are only seeing bubbles when it makes bubbles.. 

Friiy

friiy wrote:
That was the 1st thing I tried to look for I could not find any leaks I thought I did find an oily gue spraying on the side of the block I traced that gue comming from the base of the muffeler.  I test the engine agine it seems to run nice. I am waiting for snow and then I can test it properly.