I have got a Mariner 15M (2 stroke) and it's a great little engine for my purposes and goes very well on a SIB.
The only thing (well, *nearly* the only thing
) that is not quite right is that it coughs at low revs from time to time, and the revs drop momentarily as a result. They are back up within a split second, but it isn't right. At high revs it's spot on and runs well. It also occasionally stalls when dropped into neutral, which I guess could be linked.
Since my 20 mile trip today when it must have coughed about 20-30 times, I've done some research and my guess is the low speed needle/screw needs to be opened up a tad more. It was at 1 & 3/4 turns out and I've taken it up to 2. I also took it out and gave the hole a blast with carb cleaner, in case there was some crud in there too.
I know time will tell and my next trip will be the ultimate judge, but I am wondering if the consensus is that this is a good starting place?
Thanks in advance to any replies from the pros!