After run heat soaking problem in 35 HP Evinrude

[Scandia_Eagle]

This problem involves a 2004 35 HP Evinrude, 3 cylinder 2-stroke. From a cold start it runs fine, good power, strong water flow out the telltale, no limits on duration - I've tested it for 15 - 20- min at WOT and it shows no run-time problems. After shut down, it will start again and run with no problems for the first couple of minutes. After a 5 - 6 minute wait, however (long enough to go get trailer and put it in the water), the engine will fire and run in short bursts, but will not sustain operation. If it sits for 20 minutes or so, faster with the hood off, it will start and run just fine again. Have tried 3 different tanks of gas from different sources to no effect. I noted that the carburetor bowls feel quite warm (maybe even hot) to the touch - am I having some kind of vapor lock problem due to heat soaking after shut down? Other explanations for what is going on? Thoughts most appreciated.

 

[boobie]

Re: After run heat soaking problem in 35 HP Evinrude

Sounds more like an ignition prob when it gets warm. Check your spark when the prob occurs.

 

[Scandia_Eagle]

Re: After run heat soaking problem in 35 HP Evinrude

Thanks for the suggestion about checking spark - will certainly pull a plug and take a look next time out. However, it does run smoothly for short spurts and they become increasingly longer as the engine apparently cools down, so it seems to have ignition - and the ignition modules are cool, although the top of the engine around the flywheel is quite warm - could this be affecting the magnetic pickups that control the spark?

 

[hidef]

Re: After run heat soaking problem in 35 HP Evinrude

What is the model number of your outboard? The triples were only made from 1996 to 2001. If your oil injection is still hooked up it needs to be disconnected. The system is very prone to failure resulting in the destruction of your engine.

 

[Scandia_Eagle]

Re: After run heat soaking problem in 35 HP Evinrude

What is the model number of your outboard? The triples were only made from 1996 to 2001. If your oil injection is still hooked up it needs to be disconnected. The system is very prone to failure resulting in the destruction of your engine.

Thanks for the heads up - went back and checked and indeed it is a 1998 model. Sooo, maybe oiling is the problem - it does go through some, but perhaps not enough and the underlubrication is causing the motor to run slightly hot causing a mild overheating problem that becomes apparent after shutdown with no water flowing through the cooling system. I'll give it a run with a 50:1 fuel/oil mix in the tank and see what that does - will post my findings - thanks again

 

[hidef]

Re: After run heat soaking problem in 35 HP Evinrude

Run 50:1 pre-mix in the tank and pull the oil injection. Remove the tank and mixing chamber you can connect the hose running to the fuel manifold from the mixing chamber directly to the fuel filter. The cable that went to the float in the oil tank just needs to be secured out of the way. You probably have an issue with your power pack although a bad voltage regulator can cause the same symptoms you are experiencing. If you engine has electric start. Disconnect the two yellow wires going to the voltage regulator (it is behind the air intake) and see if that cures your problem. If it does your voltage regulator is bad. The engine uses an optical pickup that tends to either work or it doesn't so I don't think that is your issue.

 

[Scandia_Eagle]

Re: After run heat soaking problem in 35 HP Evinrude

Run 50:1 pre-mix in the tank and pull the oil injection. Remove the tank and mixing chamber you can connect the hose running to the fuel manifold from the mixing chamber directly to the fuel filter. The cable that went to the float in the oil tank just needs to be secured out of the way. You probably have an issue with your power pack although a bad voltage regulator can cause the same symptoms you are experiencing. If you engine has electric start. Disconnect the two yellow wires going to the voltage regulator (it is behind the air intake) and see if that cures your problem. If it does your voltage regulator is bad. The engine uses an optical pickup that tends to either work or it doesn't so I don't think that is your issue.

Great suggestions - I think the voltage regulator is something to look at - the fins were quite hot 15 minutes after shut down on the last run and they are right next to the carburetor bowls which were also quite warm. Will disconnect wires and see what happens. Everything on hold for the moment as the starter conked out and further testing will have to await getting that back in order - more later and thanks again for your input.

 

[Scandia_Eagle]

Re: After run heat soaking problem in 35 HP Evinrude

No progress to report except that starter is rebuilt and reinstalled, but now, my whole electrical system is dead - battery charged, terminals clean, main fuse is good. Can't even operate the hydraulic trim - so, some more troubleshooting to do before I can get back to addressing my possible overheating problem.

 

[hidef]

Re: After run heat soaking problem in 35 HP Evinrude

Check to make sure you didn't forget to attach one of the red wires to the starter solenoid. There are two besides the one coming from the battery. if they are both attached then check to make sure you have 12 volts at the fuse holder. If you don't you most likely have a broken wire.

 

[Scandia_Eagle]

Re: After run heat soaking problem in 35 HP Evinrude

Check to make sure you didn't forget to attach one of the red wires to the starter solenoid. There are two besides the one coming from the battery. if they are both attached then check to make sure you have 12 volts at the fuse holder. If you don't you most likely have a broken wire.

Well, I have two red wires on the left side of the solenoid and one large wire on the opposite (is this the one you mean about coming from the battery?). Continuity between one leg of the fuse and a red wire on the left side. No 12 volts at the fuse. What I don't understand is why the trim/tilt circuit is dead along with everything else - must be one main wire or connection someplace that is not working.

 

[hidef]

Re: After run heat soaking problem in 35 HP Evinrude

You have wired the starter wrong. The three red wires are all tied together on the right side of the solenoid the yellow and red should be on the left side by itself.

 

[Scandia_Eagle]

Re: After run heat soaking problem in 35 HP Evinrude

You have wired the starter wrong. The three red wires are all tied together on the right side of the solenoid the yellow and red should be on the left side by itself.

You were soooo right. Moved the two reds to the right side and Voila everything worked. Thank you, Thank you. Now back to where I was before the starter quit - sorting out the overheating problem. Have disconnected the rectifier and will give it a try this week-end - probably not til Sunday. Thanks again.

 

[Scandia_Eagle]

Re: After run heat soaking problem in 35 HP Evinrude

Well the journey continues and the plot thickens. After re-installing starter and getting it wired correctly (see above), engine fired right up. Checked voltages and I'm getting 13.65 at idle and 14.7 at wot - seems to be working okay, so I've dismissed this as the cause of my problem. Still my apparent heating problem continues, but I've narrowed things down a bit. The problem seems to occur in a warmed-up engine when it is running at idle for a few minutes - i.e. it starts to run rough, then dies. When restarted, it runs for a short burst, then gets rough and dies. I understand from my manual that the thermostat operates to control temps at idle and at wot the water pressure pushes the diaphragm open so cooling water flows through the water jacket - this seems consistent with my problem as operation at wot for 10-15 minutes goes very smoothly - it's only after I slow down to idle that after a minute or two the problem appears. So, I replaced the vernatherm, but the problem continues. So, now what? Lots of water coming out the tell-tale so I think water pump is okay, although it has not been changed in 5 years and probably ought to be looked at on general principles - just reluctant to pull the lower unit at this point. Would a clogged cooling passage downstream from the thermostat prevent the trickle of water that flows past the vernatherm from getting into the cooling jacket at idle? Question - when or what should be coming out of the port side vent next to the tell-tale port? As far as I can tell, nothing is coming out there. Where to go next? Thoughts most appreciated.

 

[hidef]

Re: After run heat soaking problem in 35 HP Evinrude

When starts to act up you need to check for spark. I hate to say it but I think your power pack is going bad.