2004 50 hp T50TLRC starting problems

[rodbolt17]

no but I can google it

[Fishhauler]

Ok Rain has stopped.

Throrope: I replaced the gas tank connection. Purchased new gas line. Purchased new motor fuel connection. Replaced the fuel water separator. It was time anyway. Still did not start.

Rodbolt17: I would love to sync the carbs but can't get it to run. Is it worth connecting the manometer and trying to start and see where the HG is at?

Boscoe99: About how deep is the hole drilled? I will try and remove the idle/fuel mixture screw and clean carbs again.

This is what I tried before dark after work. I took a rag and held it over the silencer intake to see if it would help it start. No luck. I could smell fuel after I did that. I removed the 1 & 2 plug and found the plugs are dry. I squirted a little bit of gas directly into the cylinders. Replaced plugs and tried to start. It tried to start. I kept cranking a little bit and it didn't fire again. I sat there thinking for a bit and thought maybe I didn't hose the carbs up right. I removed the carbs again to check. Looked at the manual and I have it done right. Now for the good part!!!! I never replaced the o-rings between the silencer and the plate or the o-rings between the plate and the plastic piece or the o-rings that go between the carb tower and where it connects to the motor. They are flat and looked like they might not seal. Do you think by not sealing in these places it could cause the carbs not to be able to draw the fuel into the cylinders??????? I am going to replace no mater what. I don't like the way they look. I am going to do this before I drill out the plugs on the air/fuel mixture screws. Let me know your thoughts on this. I really do appreciate the help you guys are giving.

[TownsendsFJR1300]

The seals, especially ahead of the carb to block must be correct and installed correctly.

You have a major vacuum leak there sucking air vs fuel from the carbs...

Replace all those seals, even if they look somewhat flattened out. You can use grease / petroleum jelly to help hold them in place if need be.

It should crank up after that.


Re Boscoes carb plug / part # 36 in carb #1;

http://www.boats.net/parts/search/Ya...TOR/parts.html

is what you want to remove to access that screw. Its very thin, just go slow with a sharp drill bit. It'll pull out fairly easily as Rod noted.

**And BEFORE you pull the screw out, gently turn it in counting the # of turns as a baseline when it bottoms out and record that #


BTW, using a manometer prior to getting the carbs all sealed up would be useless..

[rodbolt17]

unless they were torn, I typically don't replace the orings before or after the carbs.

you did something wrong on your carb job.

[TownsendsFJR1300]

Quote:

"I never replaced the o-rings between the silencer and the plate or the o-rings between the plate and the plastic piece or the o-rings that go between the carb tower and where it connects to the motor.


My impression is they weren't re-installed- as in none,

Fishhauler, can you clarify, were they installed just NOT new OR not installed at all?? If installed, can I assume they were properly seated?


Agreed if the 0-rings are not flattened out/leaking I wouldn't replace them either.



I have a customers 2001 Kawasaki MC that had either a carb or fuel tank valve leak.

Further investigation shows those float bowl o-rings flattened. You can also see where the remnants of fuel were leaking out the sides of the bowls.

Someone previously put GASKET SEALER over the o-rings too vs new seals trying to repair the leak. Waiting on new 0-rings now..

That's besides all kinds of crap in the carb and fuel tank (now spotless).

[Fishhauler]

Replaced orings between carb plates, checked hoses, clipped a little off tiny hoses going to accelerator pump. They showed signs of cracking just where they go over nipple on carb. Real careful about putting carbs back together. Drew down evenly as I tightened bolts. Reinstalled career bs on motor. Battery full charge. Tried to start but it wouldn't start. Notice fuel coming out of silencer if I let it crank for awhile. Just for the sake of knowing I checked the valve clearance. Intake and exhaust all in spec. Where do I go from here???????

[TownsendsFJR1300]

Did you check and see if your getting voltage to the enrichment valve, part #34 below (as Rodbolt mentioned earlier)? That literally, is your choke.

2004 50TLRC Yamaha Outboard CARBURETOR Diagram and Parts


As you noted earlier, your likely not getting enough fuel when cranking cold.

After trying to start (and failing), pull the spark plugs and see if their wet or dry. I suspect they'll be dry.

Also, with the help of another, if you can hold your open hand over the intake end of the carbs while cranking should richen the mixture up enough to start (artificial choke basically)

[Fishhauler]

Townsend,
No I did not check the enrichment valve voltage. I will go out and check after post. Will also try blocking air intake.
I thought the enrichment valve worked by voltage warming a wax pellet that using a needle valve blocked the fuel going into the carb after it starts. Can you enlighten me on how this actually works. Regardless it still needs voltage. Can I unplug one enrichment valve and plug volt meter into connection and check it that way?

[TownsendsFJR1300]

Here ya go, posts #5 and #12

http://www.yamahaoutboardparts.com/f...t-th23921.html

And this one may help:

http://www.yamahaoutboardparts.com/f...a-th24592.html

[99yam40]

being this is a 4 stroke motor and not a 2 stroke I have no idea if the prime start systems work the same on the 4 stroke 50.

The 2 stroke does operate as you said, while cold, fuel flows though and as the motor runs the heater is fed voltage that heats up the wax pellet and pushes the needle into the seat closing off the passage that gives extra fuel.
It does not need voltage to get the extra fuel into the system, just to close it off.

But that is not a 2 stroke you are dealing with.

If you have not pulled the carbs completely apart and cleaned all passage, including those in the enrichment system you are spinning your wheels with all the other things you are doing

[Fishhauler]

checked the voltage to the prime start valves. It gets voltage as soon as the key is turned.
When I cleaned the carbs the only thing I didn't do was remove the air/fuel mixture screw. I did however blow clean dry air through all the ports on the carbs. I got air through all of them.
The plug that goes over the air/fuel mixture screw does it act as a seal? Or is it just to keep people from messing around with the screw? Can I check to make sure this is clean and then try to start with out replacing the plug. Do you have to replace the plug?

[boscoe99]

checked the voltage to the prime start valves. It gets voltage as soon as the key is turned.
When I cleaned the carbs the only thing I didn't do was remove the air/fuel mixture screw. I did however blow clean dry air through all the ports on the carbs. I got air through all of them.
The plug that goes over the air/fuel mixture screw does it act as a seal? Or is it just to keep people from messing around with the screw? Can I check to make sure this is clean and then try to start with out replacing the plug. Do you have to replace the plug?

It does not act as a seal. It is to keep folks from adjusting the idle mixture screw. You do not have to replace the plug. Most do not. Early models did not even come with a plug.

If you decide to remove the idle mixture screw count the number of turns to lightly seat it. Make a note. That will be the position you use when the screw is reinstalled.

[Fishhauler]

Boscoe99,
Thanks for the info. I will record the number of turns in my manual.

[Fishhauler]

cleaned air/fuel passage. Recorded # of turns on screw and reinstalled with same # of turns. Tried to start motor. No luck. Don't believe problem is in the carbs. Checking timing marks to be sure timing is good. I am still getting fuel out of the breather when I try to start. I checked valve clearance and they are right in spec. Don't know what direction to turn now. I hate to admit defeat and take it to the shop.

[TownsendsFJR1300]

Right now, if you squeeze the primer bulb, with the fuel bowl drain screw REMOVED(one at a time), do you get fuel to the bowls?