90 hp. hard to start

[SULLY]

Can someone please advise as to what the proper starting procedure would be for a 2003 90 horse TLRB. This motor has hardly been used when i purchased it on a 2003 Skeeter Bass Boat. It takes a good cranking to get it started first time but once started will crank at the bump of the ignition all day long. I always prime the bulb before starting. I usually have to crank untill the batery starts to get weak before it will bust off. Any advise would be greatly appreciated.

[Bazooka Joe]

Beings your motor starts good the rest of the day, I would conclude that you do not have any plugged jets to contend with.

One thing to note, is that the Yam 90 has an automatic choke system, meaning- pushing the key in while cranking does nothing. There is a computer controler which pulses the choke solenoid according to the engine temperature. It could be possible that this solenoid is malfunctioning, but I am not sure if they are prone to trouble. Typically, choke (or fuel enrichment circuits) are rather large orifices and do not plug very readily.

Instead, I might suggest to review your starting technique. I have found that my 04 90hp (should be the same motor as yours) starts best if I keep the throttle completely closed (leave the high idle lever alone) and just spin the motor. In fact, if I lift the high idle lever, it typically did not want to start at all.

Try that and see if it helps.

Good luck with it.

[Bazooka Joe]

Something else I was thinking about....

Motorcycle, ATV, and snowmobile Keihen & Mikuni carburetors typically have a fuel enrichment circuit which does NOT work unless the throttle is closed. Basically, it has a secondary idle circuit which is jetted REALLY rich, but this secondary circuit is only opened whenever the choke knob is the corresponding positon.

I wouldn't be surprised if the Yam 90 is equipped with a carb with a similar system. I think the Yam 90 carbs are Mikuni?

[Ken]

Sully,
Your owner's manual should describe the proper procedure to start that 90 hp Yammie. If you don't have one, go to www.yamahapubs.com and take a look - use to they would let you take a look at the owner's manual online.
I looked at the carb setup for your motor in the diagram of the online catalog (above). The auto choke looks like it is a pump attached to the middle carb that is energized by a solenoid - there are two wires that lead to it. I will assume that the two wires are ground and (12 volt) command. You should be able to observe the pump being energized by removing the air silencer that is in front of the carbs. Do this when the motor is cold. I would guess the choke would energize only when the starter is engaged. The motor should start with the throttle in neutral and no extra idle added. You should be able to see fuel mist being squirted into the throat of the carbs. I am guessing at this, since I have never done it myself.
If you do not see any fuel being injected into the carb intake, then either the pump/solenoid is bad or the command from the ignition circuitry is not getting to the choke. Gonna need a voltmeter to test it at this point.
Good luck [img]smile.gif[/img] ,
Ken K

[SteveE]

Sully: Your starting experience describes exactly mine for nearly the first year I owned my 90 TLRC. It was particularly bad if I went for 3-4 weeks between starts. One day at the ramp a helpful guy walks by as I'm cranking away getting more frustrated by the minute and says "doesn't sound like its getting any gas, on my Yamaha I have to squeeze the primer bulb several times between cranking attempts".

Tried it, presto, it started right up and has worked ever since. I guess I was used to other makes where once you felt some resistance on the primer bulb it was primed, but not my 90. I'm talking about squeezing hard until you think something may blow and then cranking. If it doesn't fire in 4-5 seconds, stop and pump again. I've never flooded it using this technique and like yours, once it starts and warms up, just a bump of the starter for the rest of the day.

Ken may have given the real answer in that we both may have a problem in the choke circuitry. I may follow his advice and check that the next time I'm tinkering with my motor.

Let us hear what your results are.

[tripleb]

Hey SULLY,

I have a 05' TLRD ..... I have found the same thing as Bazooka Joe, if I lift the fast idle lever, the motor basically refuses to start.

I have found that pumping the primer bulb until you are tired of pumping and then turning the key for a couple of 5 second starts that the motor fires right up. This procedure is for a cold start ..... like you and others, once she starts, she is good to go the rest of the day.

I think the 90 is just a "cold natured beast"

I had a 70 Evinrude that was similarily "cold natured", maybe even worse than the Yamaha.

[Hank Austin]

Hi Sully, I have a new 05 90 2 stroke also. I find that for a cold start (not very cold here in Houston!) the following works great for me.

1- Squeeze priming bulb 5 to 10 times, it never gets hard but it does build some back pressure.(No my motor dont need no ******!)

2- Crank for 3 to 5 seconds twice.

3- 3rd crank starts motor almost instantly.

Re-starts are almost instant also.

Hope this helps, I like the instant choke that requires no manipulation on my part.