90TLRD Prime Start Issue

[mitch184]

ok... next issue on this new to me 2005 90TLRD.

when cold with the prime start in AUTO the motor doesn’t seem to start. Turn it to emergency, and it fires right almost instantly. Then turn the switch to AUTO and the motor will high idle for a couple minutes then idle down. Because of this, I believe at least part of the prime start system is working. Each time I start it I try to leave it in AUTO but it just won’t quite go. Switch to emergency and it go instantly.

It’s about 40F right now, the bulb does pump until hard and stays hard. I don’t believe you’re supposed to have to use throttle to help it start so I’m not.

i plan on cleaning out the fuel lines but wanted to know if there was something specific to look for with my specific issue. I did a lot of search on here before posting but didn’t find anything exactly like what I’m seeing.

thanks

[boscoe99]

Quite possibly the carburetors, particularly the one with the Primestart components, are in need of a good cleaning. This does not mean just spray or run some juju juice into the carburetor and think that will do it.

[mitch184]

Ok thanks. I also read that the throttle has to be at idle for the system to work. Is that accurate? I believe with the system you should just have to pump the bulb, turn the motor over 2-3 seconds. Turn off then fire it again to start. No throttle. That sound right?

in general, I was also curious if the idle mixture screws should be adjusted a little different for colder climates. Also, this motor is a jet so there is no “neutral”. There is always a load in the engine at idle... if that makes a difference for tweaking the idle screws.

[boscoe99]

Your owner's manual does not specify any advancement of the throttle prior to cranking a cold motor. Some do, yours does not. When the motor is cold it needs more gasoline. Not air. Cracking the throttle might just make a cold start worse since it lets more air into the carburetor at precisely the time you don't want any more.

The procedure is to pump the primer ball until it is firm. Throttle handle in neutral. Turn the key to the start position for a maximum of five seconds. The motor should start. Hot, cold or luke warm.

The idle mixture screws are not to be adjusted for a colder climate. In fact, your motor came with plugs over the idle mixture screws to prevent anyone from getting access to them.

There is no difference in the idle mixture setting for a motor with a jet pump versus a motor with a conventional lower unit.

The carburetors themselves and the Primestart components have very small orifices and passageways. Over time crud can build up and restrict the flow of fuel. During a cold start you need more fuel. The carburetors being clogged prevent the flow of the additional fuel needed for a cold start. Your motor is ruffly 13/14 years old. I would suspect the carburetors are the problem.

I understand the reluctant to remove and clean (or have cleaned) the carburetors. You might want to focus first on the Primestart device. Remove it and clean the internal passageways as best that you can with carburetor cleaner. Replace the diaphragm and gaskets. Maybe that will solve your problem.

[99yam40]

Did you fix the T&T you posted on in the other thread you started?

The prime start system uses a pump, make sure it works.
it needs to pump fuel thru an orifice that could plug up.
once warmed up the heater unit plugs off the orifice to stop the extra fuel needed during startup and warm up
when placed in manual on, it bypasses that orifice to pump fuel directly into the intake.
clean the carbs and everything related to fuel well, and set to specs in service manual

You are correct you should not need to open the throttle when starting these types of motors and it sounds like it is not getting fuel, so opening the throttle will just add more air not fuel.

What is the elevation where you are running that boat?
that can affect the need to re jet if too high up

[dark_star]

I have cold start issues as well.
The longer it sits, the worse the problem gets.
this is what works best for me.

1) pump bulb till it's hard
2) check direction arrow to make sure fuel is flowing towards the motor
3) advance throttle once or twice
4) turn key and crank till it fires.

[boscoe99]

Maybe more than you want to know.

[99yam40]

I have cold start issues as well.
The longer it sits, the worse the problem gets.
this is what works best for me.

1) pump bulb till it's hard
2) check direction arrow to make sure fuel is flowing towards the motor
3) advance throttle once or twice
4) turn key and crank till it fires.

Does this mean you have a motor just like his?
If you do playing with the throttle does nothing to get fuel into the motor.
there are other motor that it does

I just looked and seems you are running a F60. way different motor

[mitch184]

Thanks. I run at sea level to 500’. It’s always raining and cold up here it seems.

i believe the factory manual stated 1 1/2 turns out for the idle screws. As mentioned, I wasn’t sure if all 3 carbs should be same or if the constant load of the jet might need them to be a hair richer. I won’t adjust till after everything’s clean.

trim and tilt..... I think I solved it but am not 100% sure. I was gonna wait till I know for sure before I responded to that post. Long story short I’ve bled the crap out of the system and did it with the engine running and it helped a lot. More on that when I’m convinced it worked.

[99yam40]

Thanks. I run at sea level to 500’. It’s always raining and cold up here it seems.

i believe the factory manual stated 1 1/2 turns out for the idle screws. As mentioned, I wasn’t sure if all 3 carbs should be same or if the constant load of the jet might need them to be a hair richer. I won’t adjust till after everything’s clean.

trim and tilt..... I think I solved it but am not 100% sure. I was gonna wait till I know for sure before I responded to that post. Long story short I’ve bled the crap out of the system and did it with the engine running and it helped a lot. More on that when I’m convinced it worked.

after cleaning and putting back on make sure you follow the link and sync procedure in service manual to make sure all throttle plates are in sync. that needs to be done any time you pull and put carbs back on

[boscoe99]

Does this mean you have a motor just like his?
If you do playing with the throttle does nothing to get fuel into the motor.
there are other motor that it does

I just looked and seems you are running a F60. way different motor

But they are both gray.

[boscoe99]

Thanks. I run at sea level to 500’. It’s always raining and cold up here it seems.

i believe the factory manual stated 1 1/2 turns out for the idle screws. As mentioned, I wasn’t sure if all 3 carbs should be same or if the constant load of the jet might need them to be a hair richer. I won’t adjust till after everything’s clean.

trim and tilt..... I think I solved it but am not 100% sure. I was gonna wait till I know for sure before I responded to that post. Long story short I’ve bled the crap out of the system and did it with the engine running and it helped a lot. More on that when I’m convinced it worked.

Idle mixture base setting is one and one quarter turns outward from being just lightly seated. For all three carburetors. The type of lower unit does not enter into the equation.

[mitch184]

Ok. I know the throttle blades are perfectly synced now so I’ll do that after.

Boscoe, thanks for the clarification. I must have seen a different year or something. And all 3 carbs are set the same right? You don’t compensate anything for the middle or top carbs?

[boscoe99]

All three get the same setting. No difference between carburetors.

[boscoe99]