1990 Evinrude 140 halting

[fwunderler]

I have a 1990 Donzi F18 center console with a 1990 evinrude 140 that i bought resently. The motor cuts out at rpm's 4500 and above. It starts right up after that. It takes about three minuites for the problem to happen then it is everytime i go over 4500 rpm. The motor just shuts down but starts right up after. idle is rough but ok. motor shuts down after sitting at idle for a few mins also. but shutting down at high speeds is a big problem? Can someone help me. The OMC shop is not sure what it could be. They think ignition switch.

 

[MCM]

Re: 1990 Evinrude 140 halting

Welcome Frank,<br /><br />I think if it were the ign. switch it would have a tough time starting period, My first toughts woud be carburetion. There's a transition from the slow speed jets to high speed jets at about 4500 to 5000 rpm's.<br /><br />Its just a guess though

 

[fwunderler]

Re: 1990 Evinrude 140 halting

yes, i read about the different jets but there are 4 carbs right? how could one be doing this? I think it could be a fuel problem comon to all carbs (fuel pump or hose). OMC Tech wants to drive boat next year when it's warm. I like to go out in the winter as long as no ice.

 

[MCM]

Re: 1990 Evinrude 140 halting

Well like I said carburetion, I think a stest drive with a tech sounds like great idea, it doesn't necessarily have to be one carb, it could just be their all in need of cleaning/overhaul. It could be something else as you say. That transition is based on engine vacuum pressure also.<br /><br />But if you can get/afford a Tech to take a ride I'd jump on it.<br /><br />Good Luck

 

[rodbolt]

Re: 1990 Evinrude 140 halting

does it shut off like you turned the key off? by 4500 your way on the mainjets and long off the idle and intermediate jets. the main jet is the only one that meters fuel, the other two meter air and use a fixed nozzle as a pick up. have you tested the alarm system? is it still oil injected?<br /> do you have access to a DVA meter ?<br /> the transition from idle/intermediate is when the throttle shutters uncover the transition holes. air pressure moves the fuel.<br />google the venturi principle

 

[wilde1j]

Re: 1990 Evinrude 140 halting

I'd bet on a powerpack, keyswitch, or anything common to all holes ... carbs don't give a dead stop from 4500. You need to carefully trouble shoot before buying any parts.

 

[fwunderler]

Re: 1990 Evinrude 140 halting

Thanks everyone for the help. i am still t/s this and found the gas filter with no hose clamps on it. The engine may have sat for a while and it seems to be doing somewhat better everytime i use it. I am staying away from any rpm over 4200 and alls ok. fouls plugs alot when idleing and clears up when accelarating.