Re: Yamaha 50hp 1999 - starting with difficulty when cold
I disagree with Ray on this, I have no issues with that motor cold, as long as the enrichment circuit and proper starting method is used.
a brief overview of the "prime start" system on that 50.
it uses a heated wax pellet solinoid to alter fuel enrichment at idle .
when the pellet is cold a rod retracts and allows extra fuel to enter the intake tracts of all 3 carbs, the pellet is heated by the pick off voltage from the stator.
if the carb shutters are not properly sycnded or another issue is happening or your using any amount of warm up lever it will be very difficult to start cold.
the system actually works quite well but kicks many a techs rump cause they dont seem to grasp how it works.
as the engine runs and the pellet gets heated the rod extends and closes off the fuel enrichment passage.
on the middle carb there should be a red lever, make sure it has not been turned to the OFF position.
go on the yamaha parts website and look at the middle carb, you will see some diaphrams and orings and such that can go bad or get trash in them, those parts get overlook and are not part of the carb kit. I complained again today at the seminar about it.
but if everything is set up properly and the correct starting procedure is used those motors start fairly easy down to about 35 degrees F.
below that and I usually have to use the manual overide.
