98 Evinrude - puzzling me

[Andy D]

Hi guys, first time posting but I did do a search to no avail. I have a 98 Evinrude 35 h.p., electric start, 3 cyl., 34.5 CID. Ok twice this year, I will leave the landing and the motor runs good for a mile or so, then it just quits. It quits so fast that the water under the boat kicks the motor up out of the water! I thought it was not getting gas, so opened the fuel cap, and had buddy pump ball, but it would start and only run a minute, then quit again. We sat for a few hours (duck hunting) then fired it up, and it ran fine?!?!<br /><br />It ran fine for about 3 weeks and then did same thing again to me last Saturday. On the way back to the ramp it ran fine again. So I took out the fuel filter and that was clean. <br /><br />Couple notes, it is cold here (anywhere from 0-40 degrees) and it has happened to me with a full tank and a half full tank. The t.t. is pissing good. And even when it would only run for a second, it would allow full RPM's, so S.L.O.W. wasn't shutting me down. Any ideas.

 

[JB]

Re: 98 Evinrude - puzzling me

Hi, Andy.<br /><br />Pull the bonnet and crank her up on muffs or in the water.<br /><br />With a hair dryer, heat the parts of the ignition that you can get at with the hot air, including shooting it up under the flywheel (careful!! ) one part at a time.<br /><br />If my suspicion is correct you are having a semiconductor failure when hot. When you heat the part that has that semiconductor in it, it will quit, and you know what part is causing your problem.<br /><br />Good luck.

 

[Andy D]

Re: 98 Evinrude - puzzling me

Thanks for the reply, that was what I was afraid of! So, I have no experience with ignition systems. I was wondering, since there is only ten days of duck hunting left, can I just run it like it is,without damaging anything else? Then after the season, tear into it with avengance?

 

[backdraft]

Re: 98 Evinrude - puzzling me

Andy, I believe the problem lies in the fuel line connector that is on the motor. As part of the governmental control, emissions, there is a check valve located in that connector that prevents fuel from draining out when you pull the fuel line. Change that connector and I believe the problem should go away. When it's cold that thing locks up and will not let sufficient fuel in to the carbs. If it works , your're welcome. If it doesn't ,forget where the info came from. nevjb

 

[OBJ]

Re: 98 Evinrude - puzzling me

Nevjb....I almost buy that....except....when an engine runs outta fuel...it usually spits and sputters a few seconds before it dies. Andy posted that the engine just quits as an engine will when the ignition system fails. I dunno. Maybe I'm wrong but just sounds ignition related to me.<br /><br />Anyways...Andy...go for both. Ones gotta be right.

 

[backdraft]

Re: 98 Evinrude - puzzling me

Outboard Jim , I had that problem on one of those 35's but it certainly could be another problem. As we know, each person views his motor problem from his viewpoint and we are diagnosing from afar. Hopefully we'll surround the problem and kick its butt. nevjb

 

[OBJ]

Re: 98 Evinrude - puzzling me

Yer absolutly right nev....alot different than being right there watch'n the engine run. I liked the part about "kink'n butt".

 

[JB]

Re: 98 Evinrude - puzzling me

Let me explain how I arrived at my suspicion.<br /><br />It runs when cold, not when hot.<br /><br />When it shuts off it shuts off abruptly, a "digital" symptom. Losing fuel would be more gradual, an "analog" symptom. Mechanical siezure would prevent it from turning over when hot.<br /><br />After a cooling period it runs again. The powerpack and other external components can take about half an hour to reach engine temperature, and about half an hour to cool down again.<br /><br />Semiconductor devices (transistors, thyristors, diodes, etc.) often fail when hot and work when cold, or vice-versa. The semiconductors in the powerpack and stator can cause all of the symptoms Andy describes (as I understand them).<br /><br />Changing parts that have not proven to need changing is an expensive and amatuerish way to troubleshoot when ways are available to prove the part bad.<br /><br />Could I be wrong? Sure. I am going on what I understand Andy to be telling us. Maybe he has misunderstood what he observed, maybe I misunderstand what he means.<br /><br />The hair dryer or hot air gun should tell.

 

[Andy D]

Re: 98 Evinrude - puzzling me

Once again, thanks for all the help. I suspected ignition problems, and purposefully didn't say that, hoping that I would be confirmed. After the season, I will try the hair dryer trick, and will post results. Now I need to get my hands on a manual....any ideas? I searched for one a couldn't find one for anything newer than '94.

 

[backdraft]

Re: 98 Evinrude - puzzling me

Andy , do make a reply to this problem. Be neat to know the solution. nevjb

 

[OBJ]

Re: 98 Evinrude - puzzling me

Andy, you can get a OEM service manual from your local Johnny/Rude dealer of a generic from Iboats. Check out their store.<br /><br />And ditto on Nevjb post. Let us know what you find.<br /><br />Thanks....and good luck.