Trouble Starting Engine & Smokey Start-up 2003 90HP 4-Stroke - Any Thoughts?

[snooktarpon]

I have a 2003 F90TLRB 4-stroke. The motor sat with very minimal use (less than 15 hours) over the past 10 years so the carbs were all gummed up last year. When I tried to take it out last November, the engine would run for 30 seconds and then die and wouldn't start for 10 minutes (only to run for 30 secs and die). This spring, I had a dealer rebuild all the carbs and it was running like a champ until my last trip.

My last trip (1 week ago), the motor wouldn't start and after numerous attempts, I thought I might have flooded it (pressing the primer bulb too much). I waited about 30 minutes, and then it started, ran for 30 secs, died, and wouldn't restart (just like last November). I then waited about 1 hour and then it finally started. It died several times when I put it in gear and then it finally kept running but was running a little rough. It was late dusk so I couldn't go to WOT. I ran it for about 10 minutes that night. Then next two days of my trip, it ran perfectly. So it seems like the motor had some gunk that it had to clear.

In addition, when it starts up for the first time every morning, I get a very smokey exhaust. I checked the oil level and that is good. This started happening about 1 month after the carb rebuild.

I've been using mid grade gasoline (not sure if has 10% ethanol) with fuel conditioner (Mercury brand called Quickare).

Any thoughts on what I maintenance I can do to ensure it starts smoothly my next trip? I have to check to see if the dealer changed the plugs and fuel filter and if not, I'll change those.

Any recommendations on fuel (octane #, is ethanol OK?, etc.)?

I'm also planning on changing the oil to a synthetic like Amsoil? I'm not sure if the oil change will help the smokey start ups

Thanks in advance for your help.

[rodbolt17]

any fuel,preferably not e fuel, with an 87 octane will work.
if you don't tilt the motor at least half way up when first shut down you will get a puff of smoke the next morning.
normal and hurts nothing.

[snooktarpon]

any fuel,preferably not e fuel, with an 87 octane will work.
if you don't tilt the motor at least half way up when first shut down you will get a puff of smoke the next morning.
normal and hurts nothing.

The motor is left at the end of the day in the trimmed down so that explains it. Thank you!
This is similar to my old BMW motorcycle that has the cylinder heads on the left side and when you put the bike on the kick stand (which makes it lean to the left), you get a smokey start up.

[CatCam]

If it makes you feel any better, my 2004 90 four stroke (last year of the carburetor models) will have the same "smokey" start up if I leave the motor trimmed down for any length of time. Heck, even if I'm out on the water and shut down and fish for a couple hours with the motor all the way down I'll get the "puff" of smoke. I contacted Yamaha Tech about this and they told me not to worry as long as it clears up and doesn't do it while I'm running. I use Pennzoil Synthetic 10W-40 in mine, have over 500 hours with no issues. Rodbolt will tell you that synthetic is waste, and he's probably right but I feel good putting it in!

Now, the the running issue - probably some trash got through and logged in a carb and eventually worked its way out. Make sure you have a good inline (10 micron) filter and stay away from ethanol!

I've found two stations around me that has non-ethanol fuel. Usually you can only get the non-ethanol in the low octane (87), but that works just fine with these motors.

Make sure the dealer changed your water pump impeller, if it is the original you are on borrowed time!

Good luck!

[snooktarpon]

Make sure you have a good inline (10 micron) filter and stay away from ethanol!

I'm assuming you are talking about the fuel filter. I was planning on using the Yamaha OEM filter.

Do you get your parts local or online. If online, any recommendations?

[rodbolt17]

local or online?
that's a dilima.
cant spell, to much cool refreshing beverage.

was looking at a 9mm M70A pistol online.

every site had a low price, no stock.

bought a pretty 9mm from a local.

maybe will post how it shoots .

moral.

give your locals a chance

[CatCam]

Yep, what Rodbolt said!

I have a Yamaha Filter,
Part number: MAR-SEPAR-AT-OR
90 GPH / 10 Micron
Overall Dimensions: 4 1/4" W x 8" H x 4 1/4" D
(2) brass nuts and instruction / installation manual included!

Cost me about $60 or so I had to buy some fuel hose and some clamps...and some stainless bolts/washers to mount it. Works great and I got it from my local Yamaha boat dealer......

[snooktarpon]

local or online?
moral.

give your locals a chance

I always try to support small business over the big business (cough amazon cough). Unfortunately, it sometimes comes down to economics. If I have to spend 90 minutes of driving along with $10 in gas (SUV) to buy a $20 part, then online looks pretty good.

[99yam40]

$10 in gas to run for 90 minuite is very good mileage on a SUV