1999 90HP Mercury tough starting

sprout

Recruit
Joined
Dec 28, 2003
Messages
3
I bought a used 90HP Mercury (1999) this year. It has a tough time starting whenever I first launch the boat. I push the cold start lever forward, pump the bulb til it is hard, then turn the key and choke the engine, and then start it. It starts right up, but then immediately dies. I have to keep doing this roughly 5 to 7 times before it will finally continue to run. It seems like every time the engine starts, it is running from the fuel injected during the choke and then is not getting any new fuel. I run premium gasoline, so I dont think that is the problem. Could this be a solved by replacing the fuel line and bulb, or is this possbibly a clogged fuel filter or carbeurator problem?
 

Elmer Fudge

Lieutenant Commander
Joined
Aug 25, 2003
Messages
1,881
Re: 1999 90HP Mercury tough starting

It could be your fuel tank is not properly venting, when last did you decarb? A sticking float needle can be the cause as well. <br />If the bulb gets soft,it could be faulty or air is getting into the lines.<br />87 octane should be sufficent,i think it is manufacturer recomended.
 

mellowyellow

Vice Admiral
Joined
Jun 8, 2002
Messages
5,327
Re: 1999 90HP Mercury tough starting

prime to max just before launching, then again when<br />ready to start. don't know why, but this works for<br />a fishing buddy w/same set-up.<br />good luck,<br />M.Y.
 

sprout

Recruit
Joined
Dec 28, 2003
Messages
3
Re: 1999 90HP Mercury tough starting

Thanks for the responses, I have never decarbed the engine, so I will try that. Thanks again.
 

Erik Selis

Recruit
Joined
Dec 29, 2003
Messages
3
Re: 1999 90HP Mercury tough starting

I have a 2002 90hp merc and have had the same problems starting a cold engine. The dealer showed me a little trick that helps me out every time.<br />After priming, start the engine with the throttle a bit open. The engine will start but will tend to stall. Before the engine stalls push on the top of the ignition key (this is choking)quickly letting go. Do this a couple of times. Keep doing this if you feel the engine will stall. Once the engine is running a bit smoother, give a bit more throttle until she warms up. Once warm put the throttle into the central position.<br />The best way to describe it is : tapping the choke.<br />Regs,<br />Erik
 

sprout

Recruit
Joined
Dec 28, 2003
Messages
3
Re: 1999 90HP Mercury tough starting

Thanks for another tip. I will definitely try it out and see if it works. If it does, it will be a cheaper fix than bringing it in and possibly paying for a carberator clean or whatnot.
 

WillyBWright

Fleet Admiral
Joined
Dec 29, 2003
Messages
8,200
Re: 1999 90HP Mercury tough starting

Don't give it any throttle at all. Leave the warm-up lever down while it's cranking. The throttle butterflies need to be closed for enough fuel to be pulled out of the carbs while starting. Otherwise it'll do exactly as you describe...run out of fuel as soon as the prime charge is used up. Choke it of course. As soon as it fires, you can give it some throttle, but not until then. This is common on the inline 3's and 4's from 75 thru 125Hp 2-stroke Merc/Mariners of this genre.
 

mejg

Recruit
Joined
Dec 29, 2003
Messages
2
Re: 1999 90HP Mercury tough starting

My 2002 90 hp Merc likes to be treated as Erik described. The manual says not to allow the fast idle lever to rev the engine over 2000 rpms after initially starting the engine. The "tapping the choke" is the key to cold starting.<br />Matt
 
D

DJ

Guest
Re: 1999 90HP Mercury tough starting

The 75 (very similar) I frequently operate acts just as you described.<br /><br />As mentioned "bumping" the key in when it wants to stall is the key.<br /><br />By the way, lose the premium fuel. You're wasting your money.
 

Erik Selis

Recruit
Joined
Dec 29, 2003
Messages
3
Re: 1999 90HP Mercury tough starting

I agree with djohns19. No need to use premium fuel.<br />Erik
 
Top