Re: Yamaha 50 hp Four Stroke, difficult Starting " Cold "
Well !<br />I have as some suggested quite rightly, bided my time and waited in anticipation, and the manual has arrived.<br />As was mentioned by some, the manual is to some extent general, but nevertheless a distinct advantage having it.<br />It covers from 9.9hp
. Up too the 100hp Yamaha four-stroke O/B engine.<br />Having looked at the cold start system the 50 hp motor uses, I am still unsure as to just how it fully operates. I understand it functions via a thermal switch, and that when the temp is at a set low level the choke solenoid comes into play.<br />Basically looking at the Starboard side of the engine there is the choke solenoid and an electrothermal valve, also two thermal switches. This is all straight forward, in the manual it goes into some detail how the function of most of the various models cold start systems operate, but when it comes to this system which incidentally differs from the majority of the other engines this manual covers, it really doesnt explain it operational function.<br />Im aware at a given temperature the circuit will bridge bringing in the choke solenoid, its initial feed coming from the ignition switch bridging, this in turn being dependant upon the thermal switch, either #1 or #2 thermal switch I will study the circuitry more !<br />Given that the thermal switch sensed it was at a temperature to function, would I be right in presuming that the choke solenoid operates, if so, is it basically an on off type solenoid, in this I mean its not gradual, whether it be coming on or going off?
( not like a stepper motor ? )
would its travel depend on the thermal switch resistance even ?
or does it just operate then retract when the resistance value is met? <br />What is the function of the electro thermal valve?<br />Can the choke solenoid be powered up from an outside source, to test it ability to operate without damaging it ?<br />Sorry about the Spanish Inquisition, but I really would like to get to the bottom of this problem that thinking about has probably been with this engine for quite sometime, even prior to me owning it
. Thanks in anticipation