rough idle after engine is warm

[wsconner]

I have a 1999 2 stroke 40HP. Engine seems to run fine, except once it warms up (runinng at 3000 rpms for 10+ minutes), it coughs and runs rough once it idles down. it starts up again, but has trouble staying at rpms below 1,000. But it runs and sounds perfect under load at higher rpms? Carb cleaning in order? or other ideas? Thanks again for the very useful info on this board.
WSC

[robert graham]

Sounds like time to have carbs cleaned and set.

[99yam40]

My C40tlrx had a bad CDI and the timing at idle was at 14 ATDC instead of 7.

You might want to check compression, spark, and timing just to be sure all is well with that. fuel pump would be something else to make sure it is not leaking into crank case.

If all that is good then carb cleaning and setting by book is in order

[wsconner]

Thanks for all the good advice. Finally had carbs cleaned by dealer and it runs like a champ