1997 Evinrude 25hp problems

[tomwsk]

I have a new to me 1997 25hp Evinrude E25KLEUR which is a 3 cylinder remote. I am having couple of issues with it. Issue #1 is that at WOT the engine will go full power for only about 5 seconds and then it drops down to low rpm. It does the same thing every time. Issue #2 is that it will run until it gets warm for about 10-20 minutes and then it stalls and will not restart for a while until it cools down. I don't have much equipment other than a multimeter and a borrowed compression tester but here's what I've done so far:
-removed the oil tank and gone to premix instead, 50:1 ratio
-carbs cleaned and rebuild kits installed
-fuel pumps rebuilt with new kits
-water pump rebuilt, new thermostat
-new spark plugs and wires
-checked compression: 120 accross all 3 cylinders

While running in idle, I've taken each ignition wire off the spark plug to see if it made any difference. The top and bottom made the engine run worse, not the middle one. I've switched the coils around and the problem did not follow the coil. I've taken off the flywheel and the magnets and encoder do not appear to be chipped or damaged. I do not know how to test the optical sensor. After the engine is warm and it dies it seems to me that there might be no spark to any cylinders. I did not test that properly as I have not acquired a spark tester.

I'm running out of ideas. I dread that it is the power pack, but I don't know how to test it without spending $500 on a new one. Any help would be appreciated.

Thank You.

 

[Cofe]

Re: 1997 Evinrude 25hp problems

Is the tell tale running a good strong stream? Was the old impeller still intact, or was it missing vanes?

 

[tomwsk]

Re: 1997 Evinrude 25hp problems

Tell tale has a good strong stream. The old one was worn out but it wasn't missing any vanes. It didn't pump properly all the time, sometimes it would stop. It's very good now.

 

[Cofe]

Re: 1997 Evinrude 25hp problems

When the motor shuts down, is it too hot to touch? The motor should get to 150 degrees when the cooling system is working correctly.
I am starting to lean toward a powerpack...but not yet. Look in the sticky at the beginning of the forum. There is a section on electronics/CDI trouble shooting with some good links.

Edit...could not find the CDI stuff in the sticky...I will look at my old links to see what I can find...

 

[tomwsk]

Re: 1997 Evinrude 25hp problems

I don't have an infrared thermometer to check the temperature but it only shuts down when the engine has warmed up. Thanks.

 

[Cofe]

Re: 1997 Evinrude 25hp problems

Search maxrules in google. He has a fine site for diagnostics. Here is a CDI pdf. link on his site. CDI Electronics Practical Outboard Ignition Troubleshooting

 

[tomwsk]

Re: 1997 Evinrude 25hp problems

Thanks.

 

[tomwsk]

Re: 1997 Evinrude 25hp problems

When the motor shuts down, is it too hot to touch? The motor should get to 150 degrees when the cooling system is working correctly.
I am starting to lean toward a powerpack...but not yet. Look in the sticky at the beginning of the forum. There is a section on electronics/CDI trouble shooting with some good links.

Edit...could not find the CDI stuff in the sticky...I will look at my old links to see what I can find...

Just re-read your post. I don't think it's too hot to the touch but I will check that again next time I have it running. Thanks.

 

[hidef]

Re: 1997 Evinrude 25hp problems

Unfortunately the CDI guide sucks for troubleshooting the small triples you really need to get the BRP/OMC service manual for your engine. From your description issue (1) sounds like it is going into SLOW mode. Pull the plug with the black and yellow wire, the two tan wires and the white and purple wire going into the power pack. See if that corrects issue 1. If it does I suspect your problem is in the wiring harness or it is a (faulty overheating sensor and tan and white and black wire). I had to cut the yellow and tan wire at the plug where it connects into the power pack to cure a similar issue with my 35. The yellow and tan wire carries the low oil / no oil alarm to the power pack.

For issue number two disconnect the two yellow wires running into the voltage regulator / rectifier from the stator after the engine stalls and won't restart. If the engine starts right up the problem is either faulty voltage regulator or the stator. You will need to test both but chances are it will be the voltage regulator. If it doesn't fix the issue you might have a bad power pack which could be causing both issue 1 and 2.

 

[tomwsk]

Re: 1997 Evinrude 25hp problems

For issue number two disconnect the two yellow wires running into the voltage regulator / rectifier from the stator after the engine stalls and won't restart. If the engine starts right up the problem is either faulty voltage regulator or the stator. You will need to test both but chances are it will be the voltage regulator. If it doesn't fix the issue you might have a bad power pack which could be causing both issue 1 and 2.

I purchased an adjustable spark tester and tested the spark on all 3 cylinders while it ran. The spark jumped 7/16" without problems. I had it running on muffs and after the engine died I tested the spark and there was non on any cylinder. I disconnected the 2 yellow wires running into the voltage regulator and that had no effect. It still wouldn't start. Everything's pointing towards a bad power pack, but the CDI guide is not very clear on testing these power packs. Even the OMC service manual has a step by step guide but one of the steps is to substitute a new power pack and see if the problem is solved. That is not very useful since I don't want to spend $400 unless I'm sure that it is the power pack.

 

[hidef]

Re: 1997 Evinrude 25hp problems

I would say you have a bad power pack. The CDI guide is not good you have to use the instructions for the V4 or V6 with optical ignition. Unplug the the plug with the yellow / black, two tan wires and the white / black wire wire running into the power pack. If the engine runs than the issue is with the wiring harness which I doubt.

I have been down the same road as you with my 96 I had to replace the regulator two years ago after it smoked and the power pack last year after the engine started missing when it warmed up. It was the original power pack.

 

[tomwsk]

Re: 1997 Evinrude 25hp problems

I caved in and took it to a mechanic this morning. They emailed me a report later which said "The wiring harness in the engine compartment is a complete disaster with incorrect connections – this is probably why your engine spark has stopped working" and "Your motor will need a powerpack – it has failed"
I think they're full of crap about the wiring because the engine runs until it gets hot. If the wiring was not correct it probably wouldn't run at all. I think I'll just replace the power pack and see what happens.
They also want $969 to "Carefully sort and repair OEM connections and install a new powerpack"

 

[hidef]

Re: 1997 Evinrude 25hp problems

I find it hard to believe the wiring harness would be that big of a mess but I am not surprised to here that the power pack is bad.

 

[tomwsk]

Re: 1997 Evinrude 25hp problems

New power pack on order. In the mean time I will check the wiring to make sure there aren't any shorts or problems of any kind.

 

[tomwsk]

Re: 1997 Evinrude 25hp problems

Wiring sorted out, nothing really wrong found. Someone had some twisted couple of connections and insulated them with electrical tape. Replaced those with wire splices. Power pack replaced. Tested out on the water today. All is good. It performed really nicely.

Cofe & hidef, thanks for your help.

 

[tomwsk]

Re: 1997 Evinrude 25hp problems

Looks like I spoke too soon. Apparently I didn't test the engine in the water long enough at full speed yesterday, did lots of slow speed trolling so I took it out today. Runs great in idle and nice at WOT but it cuts out into SLOW mode I think after a minute or so. The tell tale has good strong stream at any speed. Is there a way to test that temperature sensor without running the engine?
I don't have an infrared thermometer to check the temp of the engine, but I can touch it near the thermostat for few seconds without getting a burn. The thermostat is new. I didn't want to chance disconnecting the sensor without being sure that the engine is not overheating. I did not see the overheat light light up. Any ideas?

Thanks.

 

[hidef]

Re: 1997 Evinrude 25hp problems

You can unplug the temp sensor if the engine no longer goes into SLOW mode the sensor is either bad or the engine is overheating. If the engine is pumping water I doubt it is overheating you can get an infrared thermometer at Canadian Tire. If unplugging the temp sensor has no impact. Unplug the the four wire connector going into the power pack. This is the one with the yellow/black, tan, tan/yellow and white/black wires. If that cures the problem the issue is in the wiring harness (you won't be able to turn the engine of with that connector unplugged). I recommend you cut the yellow and tan wire at that connector that wire is for the low oil sensor / no oil and if there is a short in the harness it can cause the engine to go into slow mode (I had to do this to my 35). Since you have removed the oil tank that circuit is no longer required. The solid tan wire and the white and black wire is for the temp sensor circuit DO NOT cut those wires.

 

[tomwsk]

Re: 1997 Evinrude 25hp problems

Is it safe to test this sensor in boiling water? I'd like to avoid driving half an hour to the lake to test if I can.

 

[hidef]

Re: 1997 Evinrude 25hp problems

No it is not you need to use 4 stroke crank case oil. Mobil one 5w30 or some other synthetic oil do not use conventional oil the flashpoint is to low. Here are the instructions from the service manual

You need disconnect the temp sensor and using an Ohm Meter connect one lead to the switch lead and the other lead to the metal portion of the switch.

Place the switch and an accurate industrial thermometer in the warm oil. Do not use an open flame or an oil with a flash point below 300 degrees F.

Slowly increase the oil temp

The switch must react to the changing temp as follows.

Tan/Blue switch closed 240* + or - 6* F Switch open 207* + or - 15* F

White / Black switch closed 105* + or - 3* F switch open 90* + or - 3* f

Replace the switch if your results vary.

 

[tomwsk]

Re: 1997 Evinrude 25hp problems

I just tested the switch.
White/ black closed at 105, opened at 90.
Tan/blue didn't close at all. Took it up to 255F.

I will replace but would this still cause the described condition? Should I be looking at something else?