YAMAHA 50 emergency start valve

[pine island fred]

Have a YAMAHA 50 2 stroke, 50TLR, manufactured MAY 2008. Has been in the box until I had it hung last JULY. Wanted to use it before I died but the 50 MERC it was to replace never quit. It ran sluggishly for about an hour last JULY. Due to health reasons I was not able to use it again until my attempt last weekend. The think reeked of stale fuel and understanbly refused to run. It has carbs, which is the reason I bought it, so I took them off to clean them.
This is something new to me as it has no choke or choke solenoid. The 703 controls do have a press to choke which does not do anything and the owners manual says absolutely nothing about choking. There is also no idle mixture adjustment on the carbs BTW. At any rate the center carb has a gismo attached to it with 2 wires, called an EMERGENCY STARTER VALVE. The owners manual gives very little info on it except moving a small lever on it from open to close for cold engine start.
Can someone tell me exactly what this valve does and what controls voltage thru the 2 wires attached to it. The motor still runs like hell so I am going to have to dig into it more. Perhaps a gummed up fuel pump. Thankyou FRED

 

[99yam40]

Re: YAMAHA 50 emergency start valve

Good to hear from you again Fred.
The unit is a prime start enrichment system not emergency start.

If left in the normal position it will enrich the fuel to all cylinders until the heater unit heats up the wax pellet inside and pushes the valve closed. The voltage comes from battery charging system of motor while it is running.

If things are messed up(motor will not start because of plugged up carbs) then you can turn red switch to open to allow fuel to be pumped into the cylinders to get it fired up, but once running you need to turn to closed to make it stop dumping the extra fuel.

Rodbolt wrote some good info on it back when he was posting here, so you might do some searching.
I also posted some info I came up with after rod helped me out on it

 

[pine island fred]

Re: YAMAHA 50 emergency start valve

Thank you for the greeting. Been ill and weak for awhile and lost interest in a lot of things. Am coming back and can fool with the motor. Needs a lot of TLC.
Have been out of touch with RODBOLT ( TOM ) for quite awhile. Believe he is still at JOES MARINA on WANCHESE ( close to MANTEO )
My intention was to wire that enrichment valve into the choke wires of the harness but from your description that will not work. Right now the engine is running so poorly that the manual lever has no effect on operation. My fault for leaving the motor in the box for so long.
Must be something involving pollution control as these carbs do not even have idle adjustments. I remember when you could buy kits to convert auto chokes to manual. Never saw a kit to convert manual to auto. Why would you? regards FRED

 

[99yam40]

Re: YAMAHA 50 emergency start valve

I am sure the pilot screws are under some plugs to keep non trained mechanics from playing with them( EPA stuff).
they would need to be opened up to get the screws out to clean everything properly and then set properly after putting back together.

Do not change wiring up as that would not do any good

Rod is posting often on a different forum now, I sent you a PM

He is still there in NC at Joes

 

[pine island fred]

Re: YAMAHA 50 emergency start valve

GLEEN, sure am glad you mentioned the plugs over the idle screws. Never encountered them before so did not think about them. The idle circuits must be all clogged up. Will start all over again tomorrow and do a better more extensive job. FRED

 

[99yam40]

Re: YAMAHA 50 emergency start valve

there are 2 Ns not 2 Es in Glenn
Hope you get it running well again.
Make sure passages in the prime start system are all clean as well, and make sure to Link and Sync after reinstalling the carbs.

Need to make sure all 3 carbs are opening exactly the same as the studs / holes have a little slop

 

[Capt Ken]

Re: YAMAHA 50 emergency start valve

If you can get fuel thought the carbs, mix some Ringfree or Techron 50/50 with some fuel and run it through the carbs. Mix maybe a pint of each and as soon as the jug is empty, shut the engine down before it runs the fuel out of the carbs. Let it sit for 24 hours and restart on fresh fuel. Most of the time that will clear the carbs.

 

[pine island fred]

Re: YAMAHA 50 emergency start valve

CAPT KEN, I have a few containers of the YAMAHA ring free and did that just yesterday. Then I got religion and started correctly cleaning and rebuilding the carbs yesterday. After all, thats why I bought one with carbs. I have to share this, am not making this up. Would not insult anyones intelligence.
Never worked on one before, thought they had fixed idle jet. GLENN put me on that the idle mix adjustments are underneath copper plugs which I drilled and popped out. Anytime I have taken a carb apart I have always turned and bottomed out the idle jet screw and wrote down the turns to serve as a starting reference for when I put it together. I found that both the top and bottom carb had the idle jet screws bottomed out. I tripled checked to make sure I was not mistaken. It idled poorly from the first start but did some how run for awhile. Is all back together and will light it off tomorrow.
Some of the problems are my fault as I was hoping YAMAHA used some kind of pickling fluid before they boxed the motors up. regards FRED

 

[99yam40]

Re: YAMAHA 50 emergency start valve

FRED do you think the drill bit may have hit the screws when it went through the plugs and ran them in?

Hard to believe it would have run at all with them screwed all the way in.
I think Spec should be about 1 1/2 out, but not real sure on a 2008 or 2009 which ever it is

 

[pine island fred]

Re: YAMAHA 50 emergency start valve

That was my big concern when I drilled out the first plug. Was very careful and drilled just enough. As it turned out, hitting the screws with the drill bit would take some doing as the screw heads are recessed about 3/8 to 1/2 in. in the bore. That 1 1/2 turns out is right on, one was set at that. The few times I had started the motor I have had to use either, once it warmed up with the throttle pushed up it would idle very poorly and my first intention was to turn up the idle. There still is a screw for that.
As it stands, have not been able try out my last carb cleaning as it has been raining and the no-see-ums have been out in force. Big storm hit the gulf coast this morning with heavy wind, rain and tornado warnings. Is 80 degs in the morning though. regards FRED

 

[99yam40]

Re: YAMAHA 50 emergency start valve

Hope it will give many hours of trouble free running when you have a chance to run it. the main thing is not to let it sit for long periods of time without draining carbs before the set up and keeping fresh gas in it
Let us know how it goes.

Ran out to the flats this morning with my C40TLRX and picked up 1 nice flounder and 2 nice reds, only saw 2 pods of reds tailing and caught one out of each. My motor has been great once I figured out a previous owner had drilled out the main jets and I replaced them

 

[pine island fred]

Re: YAMAHA 50 emergency start valve

A bit of an up date and more questions. After the second carb cleaning and checking the fuel pump, I did get the motor to run at a higher RPM without the wife giving it shots of either. Even managed to pull the throttle back quite a bit and it seemed like it wanted to idle. Then I got an idea. That mysterious emergency fuel valve is not a two position lever like the owners manual says, OPEN and CLOSED, but actually 3 3 position valve according to the decal on the air silencer. Third position is labeled NORMAL on the decal. I had it in the CLOSED position per the owners manual but put it in the OPEN position. Now the motor idles. I am still not sure how the valve works but it is cast in the center carbs housing and has no connection to the other carbs, One thing I did discover was that it has a small hose like an oil injection hose running to the intake manifold. I had mistakenly left it off the last time I ran the motor. Did not leak fuel.
From the first time I ran the motor, there was noticeable black smoke. So the leg was in the water and thru some quick work with the throttle I managed to put it in gear to put a real load on it. I pushed the throttle up and the motor was very unhappy, gained about 500 rpm and acted like the timing was real off. Question, there is a black box connected to the throttle. It has a metal arrow on it that moves about 90 degrees with throttle movement. What is it? I see no movement of the ignition plate thru all that linkage and am thinking that might be some of my problem. If anyone has any thoughts please let me know.
Walked away from it to let the fuel system soak in a rich mixture of gas and YAMAHA ring free just like the YAMAHA mechanics. Going down to the keys for a few day. Same KEY that TASHASDADDY use to go to. I need it, beer, fish and gin clear water. thanks for listening FRED