Mariner 50hp idle issues

"Hi there,
I have a Mariner 5

"Hi there,
I have a Mariner 50hp 4 cyl serial# 6590984. It had been sitting under a tree for years when I got it so I've done a bit to it since, including; re-wire, replaced cdi unit, starter solenoid, new plugs, new gasket kits through carbies, new impellor, fresh gear oil. Got it running (almost) nicely now - it's great through the mid to high rev range, but doesn't idle too smoothly in the water, and will usually stall if I shift from fwd to reverse. Sounds and smells a bit rich maybe. I've got the mixture screws set between 1.5 and 1.75 turns back. Also not too easy to start once it's been going, you need to give it a few herbs to get it re-started then seems a bit flooded.(?) Needle valves and seats appeared perfect, could it just be the mixture, or adjust the idle screw up a bit or something more ominous? Hope someone has some thoughts,
Thanks
Martin"

Did you thoroughly clean the c

Did you thoroughly clean the carbs when you had them apart? Rebuild the fuel pump? Final adjustments should be done with the motor in the water and in gear. This has nothing to do with bad idle but the lower unit oil should be changed and the impeller replaced as they can dry rot from sitting.

"Yes, thoroughly cleaned the c

"Yes, thoroughly cleaned the carbs - yes, replaced the impeller and lower unit oil, but no - I did not rebuild the the fuel pump - I'll have a look at that next! Thanks for your thoughts"

"Sorry IBNFSHN, thought there

"Sorry IBNFSHN, thought there must have been a separate fuel pump, which of course there's not! The carbies have the pump incorporated in them, so as part of the gasket kit I renewed all the pump components at the same time. So, still down to mixture and idle adjustments maybe?"