Evinrude Ocean Pro 225 1995 frustration with WOT

Sounds like it might be losing spark on one cylinder.----Possibly run with timing light to find which one.-----Checked for a loose flywheel magnet ?

Magnets were re-epoxied about 12 months ago. I had a shift interlock problem that mechanic fixed and in the process of diagnosing pulled flywheel and found, or caused, a loose magnet. They are all in place now.

Next chance I get to run the boat, I will evaluate the spark as you suggested.

Have you or anyone else have any tips to do these CDI troubleshooting tests?

2. In the water or on a Dynameters, check the DVA output on the Orange wires from the power pack while connected to the
ignition coils. You should have a reading of at least 150V DVA or more, increasing with engine RPM until it reaches 300-
400V DVA maximum. A sharp drop in DVA right before the miss becomes apparent on all cylinders will normally be caused
by a bad stator. A sharp drop in DVA on less than all cylinders will normally be the power pack or timer base.
3. Connect an inductive tachometer to each cylinder in turn and try to isolate the problem. A high variance in RPM on one
cylinder usually indicates a problem in the power pack or ignition coil. Occasionally a timer base will cause this same
problem. Check the timer base DVA voltage (see NO SPARK ON ANY CYLINDER above).
4. Perform a high-speed shutdown and read the spark plugs. Check for water. A crack in the block can cause a miss at high
speed when the water pressure gets high, but a normal shutdown will mask the problem.
5. Check the triggering and charge coil flywheel magnets for cracked, broken and loose magnets.
6. Rotate the stator one bolt hole in either direction and retest.

A 1000 rpm loss is a cylinder dropping....Get a old aluminum prop and make a test wheel and run it on trailer till problem happens then test. My guess is timer base or CDI pack as their QC is low these days..

Since initial post, I replace all fuel lines from tank including new fuel bulb. I also replaced the Stator based on a conversation with CDI technicians. I really felt that this was going to solve the problem-the goo material was oozing out of one of the windings. But my test run yesterday was a fail...I did not get the rpm back. I'm running 4400 max rpm. It starts easy, runs smooth, just runs out of throttle at 4400 rpm, no detectable missing at all. Bulb is staying firm, I forgot to press the choke in to see if that would help. What was unique about this test, I usually get 1-3 minutes of 5200 rpm, this time it never would go above 4400. faztbullet-the only electronics I haven't changed is the timer base, should I get CDI to send me a replacement pack before replacing timer base? Any other thoughts?

Sounds like it is running on 5 cylinders.-----Some testing needs to be done.----Guessing / replacing parts gets expensive.

Make you a test prop so you can get it to RPM, hook a timing light to the org primary wires to coils and see which cylinder drops.

Thanks guys! I have one last shot at trying to get this figured out before a big trip and have the time to replace the timer base, but not enough time to diagnose it correctly using a test prop or the guts to try the WOT shutdown test. I have used the boat for over 200 miles with the max WOT of 4400 rpm, so I don't believe another 80 miles will cause additional problems.

Everything is new electronically (powerpack, coils, wires, plugs, rectifier) except the Timer base. I have talked with CDI and they, too, recommended testing instead of warranty replacing their powerpack. The common sense that he said was the old powerpack did it, and the new powerpack is doing it, why would it be the powerpack? I have to agree.

Question: Is there a possibility that the Timer base could be wacky and causing the WOT loss (aka cylinder drop)? Or, am I absolutely throwing $300 down the drain by replacing it. Thanks!

Its possible it (timer base)could be dropping a cylinder but......I have seen a bad flywheel do this also.

pump the bulb when you drop from 5200 to 4400 and see if that makes a difference, might have enough fuel at 4400 to run, but not at 5200, and also hit the choke like you said earlier and see if that make a difference.

I had a issue once where I rebuilt 3 VROs and bought a new one only to find out my problem was not the pump, but a fuel restriction...inline fuel filter.

Do a cylinder drop test on it to see if you can narrow it down to any one cylinder or cyls and go from there.

What kind of prop. hub ?

Your not getting rpms , ok

I replaced the timer base before last week's trip and was convinced that it was the problem. The old timer base had stator goo on the inside. But, no joy. I ran 60 miles up and down the MS river with a max 4200 rpm. No other symptoms as before, idles and runs smooth up to 4200. So, I have punted and taken the boat to the mechanic. I will let everyone know the diagnosis. I realize I left off one vital piece of information in #3 comment of this thread: After the carb rebuild and new reeds, i needed a mechanic to fix a shift interlock problem I caused when I did the carbs. He failed to torque the flywheel nut correctly. I was running 5600 rpm, with no RPM drop out, I pulled back throttle. and the flywheel spun. I got pulled back home and mechanic correctly torqued flywheel. This incident coincides with the problem. I just felt like it was an electronic issue, not a mechanical issue. (FYI: I looked at flywheel -Magnets look good, center magnet in place, and no prop change.)

Boomerhuntsduck said:

I replaced the timer base before last week's trip and was convinced that it was the problem. The old timer base had stator goo on the inside. But, no joy. I ran 60 miles up and down the MS river with a max 4200 rpm. No other symptoms as before, idles and runs smooth up to 4200. So, I have punted and taken the boat to the mechanic. I will let everyone know the diagnosis. I realize I left off one vital piece of information in #3 comment of this thread: After the carb rebuild and new reeds, i needed a mechanic to fix a shift interlock problem I caused when I did the carbs. He failed to torque the flywheel nut correctly. I was running 5600 rpm, with no RPM drop out, I pulled back throttle. and the flywheel spun. I got pulled back home and mechanic correctly torqued flywheel. This incident coincides with the problem. I just felt like it was an electronic issue, not a mechanical issue. (FYI: I looked at flywheel -Magnets look good, center magnet in place, and no prop change.)

Click to expand...

Wonder if the "center magnet" as you call it, moved.

It’s fixed! Mechanic did what you all suggested-he did quality troubleshooting in under an hour! He Found #2 cylinder dropping out when it warmed up. Replaced coil, boat runs 5200rpm. 1 hour of labor and a coil and he fixed it.
I replaced all the coils when I changed powerpack early on in this problem. I believe the powerpack was faulty but I had bad luck and made a second problem with a bad coil. Who would have thought a new coil out of the box would be faulty? Thanks for all your replies.

So ----Simple trouble shooting as per post # 2 on here ?

Biggest problem with these coils is overtightening and improper placement of grounding washer. Overtightening breaks the powdered core internally and cause weird symtoms including double firing.

Good to hear your problem was resolved. I had the same issue happening to me with a 70hp evinrude engine. Seems as if it was only running on 2 cylinders instead of 3. Followed the electrical trouble shooting and found that I had a bad ignition coil. Replaced all three ignition coils with (new) CDI ones. Lake tested and boat performed as it should for all of 10 minutes. Then the same symptom returned, seem like it was back to 2 cylinders. I just knew the ignition coils wasn't the issue as they were brand new. So i began to look at all other things such as flywheel, timer base, and stator. All checked out fine. Decided to retrace my steps and start over with the electrical trouble shooting procedure. Found that the (new) CDI ignition coil was faulty. Swapped it out and Wa-La! Running on all 3 Cylinders! CDI's Quality Control is something to consider when buying their parts. Get it and test it before installing.