Merc. Won’t Idle?!?

I have a 2000 Merc 150 XR6, having trouble with it at low rpm. If I idle for more than a couple minutes, it dies. Pump the primer bulb and it starts right up, but have to keep pumping bulb to keep it running. Cannot find any leaks in bulb or fuel line. Has anyone experienced this promblem? My mechanic cannot get me in for a couple weeks and I don’t want to lose a lot of time on the water!
The motor will run great all day above 30% throttle, but not below. I’d love any suggestions!
Thanks,
John

Sounds like the check valve in the primer bulb. Swap the bulb out for a new one. If nothing else, it’s a $5.00 shot at the problem.

PS. I have that exact motor and have had the same problem with the Stock Merc part. I have been using the “Attwood” primer bulb for a few seasons now with no problem.

Buy a Yamaha!!

Got a buddy that had the same problem…Jon is right on.

Jon, who carries the Attwood bulb? Gander?

Fleet Farm has them.

-J.

Thanks

I had the same problem on my HPDI Yammie and swapped in the hi-flow atwood primer bulb and that fixed it right up. This isn’t just a merc dealie here this time.

Hmmmm, now that I think of it I have a merc primer bulb too, one more poject for tomorrow’s list. I’m tired of dealing with the stupid thing for the last three years.

could that be a problem even for a 2 stroke merc??? i have a 75 horse and have had the gas line all tore up, i think right now it is being held together by bailing twine and fencing wire.

thanks

shane

Thanks guys, replaced the primer bulb and all is well. Runs like the Yammie eater I wanted and will idle again! Shane, this is a two stroke. Give the bulb replacement a try. Inexpensive, easy, and quick fix!
John

thanks for the discussion guys, our fleetfarm in Lakeville did not have them so have ordered my attwood from the local boat shop, if this solves my idling problems, I’ll probably shoot someone. thanks Jack..

ok guys, I have another merc question for you. My merc 700, 70 horses under the cover is only running on 2 cyclanders. instead of taking it into a dealer to have it fixed or even looked at for alot of $$$ i was hoping that i could get some trouble shooting from you guys and then that might narrow it down. I have tried new plugs in it 3 times and still get the same result.

thanks for the help guys

shane

Gander does have them, I made the mistake of trying one of the primer bulbs from fleet farm, I would’ve been better off with the crappy stocker. In fact I just bought the whole new fuel line from gander, at $15 I got a perfect setup. Other brands were a bit more, after one trip with this new bulb, I can already tell it’s 100Xs better, it just feel like better quality, out of the box too. No doubt it improved how my motor is running.

Shane, if it’s a 4cylinder motor, it might be that one of the coils is blown (ouch, big $$$). All of the 4-cyl bikes I had ran only two coils, coil #1 sparked 1&3 at 180° apart, coil #2 sparked 2&4 in the same config.

Have you checked for spark by holding the plug against the block and cranking it? Use a screwdriver with a wooden or plastic handle to do this please, otherwise you’ll get a good test of your vertical leaping abilities. If you’ve got two dead cylinders that connect to the same coil, there’s one more test you should really run before declaring the coil bad.

There should be another input to the coil that goes to your points (or equivalent). Switch that input between the two coils and see if the dead spark follows the points or the coil. The motor won’t run with them switched, but you should get a visible spark if you ground the plug body against the head.

Another possibility is that you don’t have +12 going to the ‘front’ side of the coil.

Good luck and let us know how you come out.