F50tlra

[coptordoctor]

Hey Guys I have a 50 Hp Tiller that is a Bitch to get started after it sits for a bit? I see no Chioke on this or am I missing something. Does it have a Cold start enrichment feature otr something. It takes hitting the key like 20 times before it will fire. After it starts and runs for a bit you can let it sit all day but the next day same thing? Idea's?

[panasonic]

Just too confirm...4 carbs right?

It has not one...but TWO "prime start" electro thermal valves on it. One on the top carb and one on #3??

Any way you can see them there easy enough, two wires going to each of them. Remove the valve assy and hook it up directly to a 12volt battery, the pin (or needle) should extend after a couple of minutes. That's the choke system.

[coptordoctor]

Thanks So Much..
for sure i will check this sorry so long to reply i really only use this Outboard for a few trips in the fall for Deer hunting.
I just returned and it was the same problem. I will definitely have a look and get back with results..

[99yam40]

do you pump the primer bulb until it is hard to fill up the float bowls with gas before hitting the start button?

[coptordoctor]

Yes for sure did that and while it is turning over I continue to squeeze it seems to make no difference.
Here is a question where does the Chioke or enrichment system get it's power from is it just 12 volts off of the battery or does it come from the computer?
I maybe should check and see if it is getting power from the motor? That being said it will have to wait till spring as it's Minus 26C here today and it's under 2 ' of snow

[99yam40]

the power comes from the lighting coil while the motor is running.
it heats up and closes off the extra fuel as the motor warms up.

if the passages are plugged up or if the needles do not retract to allow fuel to flow when cold there will not be any enrichment

[ChuckB1954]

Are you talking about the prime start and the choke solenoid? The two large devices bolted to the carbs?

This is from one of my past posts when I was getting my carbs sorted out on my 99 F50TRLX


The prime start gets its voltage when the ignition is turned on.

The prime start works like a timed plunger or solenoid. When power is dropped, when the engine is shut off, the carbs slowly becomes choked as the prime start cools down. When you start the choked engine, the prime start slowly releases the choke and within a minute or so the choke butter flies are wide open. Turn the engine off and the prime start slowly chokes the carbs again. The temperature of the engine has no affect, although once the prime start warms up, the cycle is a little faster. Kind of a wacky setup.. You would think the unnecessary choking of an already warm engine would fowl the plugs, but it is not the case.

The choke solenoid gets it's voltage from the ignition switch and the thermal switch.

How the choke solenoid works..It will only activate the choke under two conditions.. 1: Engine must be cool enough for thermal switch to be closed..2: Prime start must have the choke released. These 2 conditions are almost impossible to exist at the same time. By the time the prime starter has released the choke, the engine is warm enough to disable switch two, disabling the choke solenoid. In turn by the time the engine has cooled down long enough for switch 2 to be closed, the prime start has already cooled down long enough to close the choke. Apparently the designer of this system wanted to ensure that this engine is choked when started, no matter what, whether the engine is hot or cold. Looks like the solenoid choke would never be used in South Florida, but this system may be useful is freezing weather.

[TownsendsFJR1300]

Are you talking about the prime start and the choke solenoid? The two large devices bolted to the carbs?

.

No choke butterfly's

:https://www.boats.net/catalog/yamaha...lra/carburetor



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[robert graham]

Are the Primestart levers in the normal position?

[ChuckB1954]

No choke butterfly's

0ops! Only a 3 years newer than my engine, but quite different.

[boscoe99]

Four stroke. No Primestart on/off/automatic lever.

[coptordoctor]

Are the Primestart levers in the normal position?

Not sure what you mean are they in the normal Position. I pulled the carbs off and pulled out the enrichment valves. When I apply power it takes a few seconds maybe 30 they close so I guess when they are cold they are in the correct position.
If they did not close i would suggest that the enrichment or choking procedure would not stop causing the engine to run rich this does not seem to be the case.
So what I am understanding here is when the engine is cold fuel is allowed to travel in the Passage where the enrichment needle is allowing more fuel. when the motor warms it closes stopping the extra fuel. So really the only thing that could stop this is if something is plugging both enrichment jets very confusing what ever happened to just having a manual butterfly.. LOL
Like I said the motor when warm starts right up in 1 sec. When cold like over night or when down to Freezing temps it take 20 turns of the key or more to get it to fire then it quits then starts and quits this goes on for about 10 more times till I can get it to sit and idle. Once warm it runs great.. Thanks for all the input ..

[99yam40]

post #11 covered the on /off/auto switch not being on your motor.

how cold is it where this problem is showing up?
maybe it it just too cold and not enough fuel is getting thru the auto enrichment system.

seems like I remember someone from up far north some time back mentioning he had a problem like this and he found way to open up the needles somehow.
it may not even had been on this forum

you may need to be real sure all of the passages/jets are clean/clear
heated sonic cleaner and a complete teardown may help

[coptordoctor]

Ok well My valve or needles are fully extended as they sit in the carb . When i apply 12 volts then then retract. seems like they are backwards. I measure the wires going to the enrichment vales and i have no 12 volts coming from the motor. Where does this 12 volts come from? This is maybe where the problem is. It takes about 10 seconds for them to retract pulling them off their seat which would mean if I am understanding this correctly enrichment will happen then as the motor warms up the valves are then extended and close the enrichment as the wax expands. I may just resort to putting a manual primer in it really does not have to be that cold out. It happens overnight in most cases. If the motor is running once then it starts fine for the day..