1985 Black Max idleing problem

[sdyarman]

I am having problems with the motor at idle. I have Checked the carbs and fuel and that is all ok. Took a spray bottle with gas in it and sprayed around the carbs when gose to die and it makes no differance .If anybody could give me any info would really appriceate the help. The motor runs fine anything above idle. when you bring it back to idle it just shuts down.It will run fine also when i first start it. Seems like when it warms up it shuts down.Thanks for any help.Steve

[fountain-boy]

what RPM does it try to idle at?

[Avenger]

What fountain-boy said. Check the manual to see if you're trying to idle it too low.

If not the idle jets in the carbs are probably plugged with "stuff". Since they're the smallest jets they're the first ones to go. Has the engine or the fuel been sitting for a while? Got filtration?

[sdyarman]

What fountain-boy said. Check the manual to see if you're trying to idle it too low.

If not the idle jets in the carbs are probably plugged with "stuff". Since they're the smallest jets they're the first ones to go. Has the engine or the fuel been sitting for a while? Got filtration?

The idle is 750 rpm and no it has not been setting . I have been running the boat since april .I have a fuel and water seperator on it . As far as the idle jets i took a spray bottle with gas in it and sprayed gas aroud the carbs that is what a guy told me to do at shorts marine he said if the idle jets were plugged it would pickup when i sprayed the gas around the out side of the carbs but when i do that it dosen't change anyting. Thank you for your reply.

[jawz12]

The idle is 750 rpm and no it has not been setting . I have been running the boat since april .I have a fuel and water seperator on it . As far as the idle jets i took a spray bottle with gas in it and sprayed gas aroud the carbs that is what a guy told me to do at shorts marine he said if the idle jets were plugged it would pickup when i sprayed the gas around the out side of the carbs but when i do that it dosen't change anyting. Thank you for your reply.

did you email me concerning this ???

anyway...

you're gonna need a dva meter,odds are you've got an ignition voltage problem,not a fuel issue...gimme a call later today...609-214-7556...late afternoon...

[sdyarman]

did you email me concerning this ???

anyway...

you're gonna need a dva meter,odds are you've got an ignition voltage problem,not a fuel issue...gimme a call later today...609-214-7556...late afternoon...

Yes i did Thought was a fuel problem at first then talked to a guy at shorts marine he told me to spray gas around the carbs with aspray bottle when it started to die he said should pickup if you have a blocked jet i did this and it didn't make any differance.fuel system seems to be ok i checked it over pretty good and i maintain it good to. Thank you. Steve.

[Avenger]

I may have missed something here... When you say you sprayed gas around the carbs, where exactly are you spraying this gas?

You'd have to spray it in the intakes to make any difference. That would make up for the engine not getting fuel if the jets were plugged. Unless Black Maxes are different than all the other carbureted outboards that I've seen, spraying it on the outside of the carbs is only good to detect a vacuum leak. Or start a fire.

Other than that suggestion, I turn you over to the capable hands of our resident mechanic jawz12. He's seen a lot more of these things than I have. Best of luck solving your problem.

[franco802]

Clean out those jets!! Also, make sure you have good gas. Two stroke right? If so, make your your ratio really good. I use to own a black max 150 v6 two stroke. They get sensitive if you don't mix the gas/oil right. Mine had the same problem, might be time to rebuild those carbs. The kit is pretty cheap.