choke/enrichment issue, floods out in gear

[Rogerthat]

2005 Yamaha 70hp 2 stroke. starts fine, runs rough at higher throttle not in gear. Will run at lower rpm in gear and craps out upon throttle. Changed the fuel filter, changed fouled plugs, ran it dry of fuel and put fuel line in brand new gal fuel can to test, no change. Plugs foul and it acts like the "choke" is stuck. I have read that I don't have a choke and little about the enrichment solenoid as far as starting but my issue is running at speed. starting is fine. any thoughts on this or other causes would be great, thanks!

[robert graham]

Check your fuel pump for a bad diaphragm causing raw gas to get sucked into crank area and making a rich mixture situation....remove fuel pump but keep the hoses hooked up, pump primer bulb and look for fuel coming out of pump back port hole....new pumps are about $50 and those diaphragms do wear out and get holes in them....it's a cheap/easy fix if that's your trouble....

[Rogerthat]

Thanks, I did pull the starter assy/enrichment solenoid... I think its defective. The plunger part with the needle in it is very loose,wiggles, seems to be extended out farther than it should be. found an actual size pic on line and its 1/4" longer. The whole plunger springs in and out, not just the pin. Hope that's it because I ordered a new one on line.

[robert graham]

Thanks, I did pull the starter assy/enrichment solenoid... I think its defective. The plunger part with the needle in it is very loose,wiggles, seems to be extended out farther than it should be. found an actual size pic on line and its 1/4" longer. The whole plunger springs in and out, not just the pin. Hope that's it because I ordered a new one on line.

It could be that Primestart assembly gone bad....Hope that new one fixes your problem!....

[Rogerthat]

Of course the more I read and think about it I better check your suggestion. Ive only had the boat a year and it always took a while to start but then ran great. The starter assy might be bad but reading about how it works, it dose not sound like it should effect the way it runs after its starts....
I got it out the other day, took off great ran great for 15 min. stopped the engine to fish for a bit, started up and couldn't push it more than headway speed and it crapped out. Puttered around started and stopped a bunch of times throughout the day but could not get it over headway speed until on the way back in I had my buddy pump the bulb a few times as I accelerate and it took off and ran fine BUT that's the only time that trick worked... Coincidence?
So, still looking for answers..

[rodbolt17]

at least you will own a spare electrothermal valve.
by your buddy pumping the primer he bypassed the fuel pump and manually filled the carbs.

[Justafloat]

Thanks, I did pull the starter assy/enrichment solenoid... I think its defective. The plunger part with the needle in it is very loose,wiggles, seems to be extended out farther than it should be. found an actual size pic on line and its 1/4" longer. The whole plunger springs in and out, not just the pin. Hope that's it because I ordered a new one on line.

Hi Roger that

I was curious as to where you found a pic of the electrothermal valve. I'm also having issues with this part with the center pin seized. I took the valve apart and reassembled now it moves about 5mm in about 1.5minutes. I've just posted to try and find a pic or some sort of specs to make sure I haven't over tighten it.

Thanks .

[TownsendsFJR1300]

Here ya go, part #33;

2005 70TLRD Yamaha Outboard CARBURETOR Diagram and Parts

I would think when its cold, it would open (suck in) immediatly to allow extra fuel for a COLD start. It should eventually close as the engine warms up (no choke eventually)..



New parts format!!!

[boscoe99]

Hi Roger that

I was curious as to where you found a pic of the electrothermal valve. I'm also having issues with this part with the center pin seized. I took the valve apart and reassembled now it moves about 5mm in about 1.5minutes. I've just posted to try and find a pic or some sort of specs to make sure I haven't over tighten it.

Thanks .

[almetelo]

Boscoe you're a excelent provider of data/info

Thanks for make my data better

[boscoe99]

You are most welcome.

What do you say in Portugal that would be the equivalent of ciao in Italy or cheers mate in England?