1995 V4 looper running on 3 cylinders

[RoyE]

The Evinrude starting on running on 3 cylinders all of a sudden, while running 4000-6000 rpm. Fourth cylinder came back after few seconds. Stopped to troubleshoot and couldn't find the problem. Than started engine again and ran problemless for about half an hour. Then it returned. Problem got worse and in the end the engine was running on 3 cylinders for 1-2 minutes, then 4 cylinders for 1-2 minutes, then 3 cylinders for 1-2 minutes, and so on. I cannot detect a certain condition in which this occurs.

Ran engine in the dark. Noticed arcing from power coil from cylinder 3 to ground. Also arcing between the plug wires from cylinder 1 and 3. And noticed arcing over the porcelain of plug number 4. The plugs were NGK BPZ8HS-10

Replaced all coils and plug wires with new ones from CDI. Also replaced all plugs with Champion QL78YC.

Ran the boat again. Ran great for about half an hour, then same problem occured.

So I think this could either be the powerpack or the sensor coil then. Correct me if I'm wrong. I do not have a DVA meter (yet) to diagnose the sensor coil (peak voltage), but I can measure the resistance values later this week.

- Based on the events I assume this only happens with engine warmed up
- Making passes at full throttle will definately cause it to run on 3 cyl again

Would a defect sensor coil give an intermittent problem like this? Is this probably the powerpack? I do not have a spare engine or spare parts, and I don't want to waste any more money in just throwing parts at it.

[jjmalkow]

It was my rectifier when I had issues with it running on 3cyl. Swaped out and no more problem

[flabum1017]

check/clean the grounds on the powerpacks.........

[RoyE]

It was my rectifier when I had issues with it running on 3cyl. Swaped out and no more problem

How did you diagnose? Disconnect rectifier from stator and run engine? (I read this in the CDI troubleshoot manual if I remember correctly)


check/clean the grounds on the powerpacks.........

Did that already but forgot to mention it.

[MattGreen]

Failed OMC power parks are a lot more common than failed timer bases (sensor coils). Your best bet is to clean the grounds as already mentioned. Some people also either run a supplemental ground wire to the pack stud or run the pack's ground wire directly to somewhere on the block (instead of grounding through the rectifier, which is kind of a crappy way to do it). If that doesn't work, scrounge up a DVA meter as you mentioned to avoid buying needless parts.

Matt

[jstatham]

I am having the same problem with my 1994 looper running on three cylinders and I actually made a DVA adapter for under 10 bucks. It was pretty easy. Check out the links below on how to make one. Let me know if you have any questions.

Here is my thread on iboats where I get the parts on ebay for cheap.
http://forums.iboats.com/forum/boat-repair-and-restoration/electrical-electronics-audio-and-trolling-motors/8844506-dva-adapter-help

Here is where I got the schematics.

http://forums.iboats.com/forum/engine-repair-and-maintenance/johnson-evinrude-outboards/380403-how-to-make-a-dva-adapter-for-multimeter/page5

Below are my pictures. If I had it to do over again I would of made the test lead wires longer at least 6 ft. It took about 10 minutes to make and I used an old external PC hard drive container to house the components but you can use anything. Google homemade DVA on and look at all the pictures to get ideas. It is pretty simple.

309067 309068

Here is a direct link to all the parts on ebay deliver for $6.06. All you need now is a little solder and some wire and some test leads.

http://www.ebay.com/itm/NTE-NEVH2-2M450BC-CAP-2-2uF-450V-RADIAL-NEVH2-2M450BC-/360796016668?pt=Vintage_Electronics_R2&hash=item54011e501c

http://www.ebay.com/itm/400611038332?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

http://www.ebay.com/itm/400727917682?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

[RoyE]

Thank you guys for the input. I'm going to make my own DVA adapter.

jstatham, what was the problem with your looper?

[jstatham]

Thank you guys for the input. I'm going to make my own DVA adapter.

jstatham, what was the problem with your looper?

i don't know yet I am still fighting it. When i figure it out I will let you know.

http://www.screamandfly.com/showthread.php?300585-1994-Johnson-120-TLERC-Help-again!!

[perfmarine1]

Do the ohms checks on the stator and timer base till you get the DVA you may find a problem. Also take a good look at stator for burnt coils or potting seeping out. Like Matt said more than likely a pack.

[powerabout]

Is the engine charging correctly, non sealed battery being used, all those leads and terminals in good condition?

[RoyE]

Do the ohms checks on the stator and timer base till you get the DVA you may find a problem. Also take a good look at stator for burnt coils or potting seeping out. Like Matt said more than likely a pack.

Thank you. I will do the checks this weekend hopefully, I can also do the peak voltage tests, made the DVA adapter today with the parts that were mentioned. Will also pull the flywheel if I can get my hands on a harmonic balancer puller this weekend.

DVA adapter, not bad :smiletest:
309144


Is the engine charging correctly, non sealed battery being used, all those leads and terminals in good condition?

What exactly do you mean by non sealed battery? I will check battery charging this weekend with the multimeter. I think however that it is charging correctly, otherwise I think it would be empty by now by using the trim and the hydraulic jackplate. All leads and terminals are in good condition, cleaned them. Boat was just rigged last spring.

[powerabout]

Thank you. I will do the checks this weekend hopefully, I can also do the peak voltage tests, made the DVA adapter today with the parts that were mentioned. Will also pull the flywheel if I can get my hands on a harmonic balancer puller this weekend.

DVA adapter, not bad :smiletest:
309144



What exactly do you mean by non sealed battery? I will check battery charging this weekend with the multimeter. I think however that it is charging correctly, otherwise I think it would be empty by now by using the trim and the hydraulic jackplate. All leads and terminals are in good condition, cleaned them. Boat was just rigged last spring.
its over voltage and loose terminals that kill them and overheat the stator which also has your charge coils in it

[RoyE]

I have the OEM service manual. There is section which describes how to test each component: stator, sensor coil, powerpack and ignition coils. I understand the description of every test, except for the one of the powerpack.

It states that I have to connect a load adapter to the ignition coil primary lead to test the output. I do not have a load adapter. Why can't I just connect my DVA meter red lead to the ignition coil primary lead, and my DVA meter black lead to a clean engine ground? Is it harmful to test it this way?

For the running output test, it states that I have to use "terminal extenders" to extend the terminals of the ignition coils in order to test the voltage with engine running. I do not have the terminal extenders. Is it possible to do it without the extenders? If yes, how do you guys it?

Thanks for all the input.

[perfmarine1]

If I can't find the problem with a ohm and DVA tests, then I do a run test with DVA and piercing probes hooked up to wires out on the water or with a test wheel. Watch the meter and just before the miss you will have a drop in voltage. Start with the coil primary wires and work backwards to the stator. If none of the coil primary wires show a drop in voltage your problem is somewhere else. Unless it's the timer base sometimes.But I can tell you it would be rare to be the timer base. However one was a v4 looper with a bad timer base.
I think I have only had to do that 3 times in 30 some years of working on outboards.

[RoyE]

You could say that's pretty rare then, I also read on other topics that timer base rarely is broken.

Today I tested voltage and ohm values of both stator and sensor coil with a cold engine.

Everything was within spec except for the stator resistance: it was 395 ohms while manual states 480 +/- 50 ohms
Output of stator was 216 volts.

The voltage output of the sensor coil was within spec, but:
Starboard terminals all read 3+ volts
Port terminals all read 1.6-1.9 volts.

Manual states that 0.5+ volts is ok, but why are values on side all significantly higher than other side?

I couldn't test the output of the primary orange trigger wires from the powerpack. (see previous reply)

Tomorrow I'm going to run the engine in the water, until the point the problem occurs. I want to disconnect the white/black wire from the temp sender. If problem then goes away I think it's the sensor coil. If problem still exists I think it's the powerpack. Just to be sure I'm also gonne try with the yellow wires from the stator to the rectifier disconnected.

To try and measure output values when the problem occurs is hard I think, since the problem always dissappears after one minute or so and I will be on the water leaning over the engine. I could later on try a setup like perfmarine1 described.

Keep you posted.

[RoyE]

Yesterday I went on the water for some testing.

I was amazed at how terrible the engine ran, from the moment I started it. Looked like it was running on 3 and sometimes even 2 cylinders. When put in gear I had to keep the throttle on, or it would shut off. I played with the QuickStart line from the temp sensor and this made no difference, but I could hear that the function was working. So in conclusion, the engine ran very bad using both sensor coils (normal one and QuickStart one).

I noticed that starting with the black/white wire disconnected, QuickStart was engaged. When I connect the wire (with warm engine) Quickstart was disengaged. When I disconnect the wire again (with engine running), QuickStart would not re-engange! Is this normal?

Engine kept running terrible so I tried my second idea and disconnected the two yellow wires from the rectifier/regulator, started it up again, and it ran as it should! Went boating for 10 minutes doing 5000+ RPM constantly and no problems at all, until SLOW activated, a problem I haven't had for months. Just to be absolutely sure I connected the rectifier/regulator again, and the engine still performed like it should. Now I'm lost here?? Is the rectifier actually bad? Ran it for a couple of WOT runs and then SLOW activated again. What is going on here?

I think the activation of SLOW is a second, additional problem? I'm am absolutely sure the engine is not overheating. I run the engine quite high on the transom for a standard lower unit, but water pressure is 30+ PSI at WOT at any time.

Are the results on the water an indication that the rectifier is bad?

I do that think I can rule out the sensor coil being bad.

Tonight I will test the rectifier using a multimeter.

[RoyE]

Ok, I tested the rectifier and used the method that is described here: iboats (http://forums.iboats.com/forum/engine-repair-and-maintenance/engine-frequently-asked-questions-faq/195576-small-rectifier-test-by-joe-reeves)

The results were as following:



Multimeter black lead to ground, multimeter red lead to:
Yellow 0.56 MegaOhm diode test: 1
Yellow/Gray 0.48 MegaOhm diode test: 1
Red ∞ (no contact) diode test: 1

Multimeter red lead to ground, multimeter black lead to:
Yellow 0.26 MegaOhm diode test: 1
Yellow/Gray 0.24 MegaOhm diode test: 1
Red 0.42 MegaOhm diode test: 1

Multimeter black lead to red wire, multimeter red lead to:
Yellow 0.11 MegaOhm diode test: 471
Yellow/Gray 0.22 MegaOhm diode test: 1

Multimeter red lead to red wire, multimeter black lead to:
Yellow ∞ (no contact) diode test: 1
Yellow/Gray ∞ (no contact) diode test: 1


I'm not sure on the reliability of the Ohm tests, so I also did the diode tests.

I'm pretty sure the rectifier is shot, can someone confirm? :rolleyes: Did I do this properly?

[RoyE]

Ordered new rectifier... waiting for it to arrive

Checked diode in engine harness, it's working like it should. Activation of SLOW should either be the temp switches or the powerpack then.

Also measured the resistance between the two yellow wires from the stator, and this was 0! I cannot find any info on what it should be. But I can hardly imagine it should be 0 ohm?

[rsukup]

I have an 87 140 Johnson. Over the years have had problems with the rectifier and power pack. I have heard the tach will not work if the rectifier is bad. The power pack showed faulty with erratic timing light on each cylinder. Question why the plug gap spec is now .030 instead of .040 since the power gap plugs are .050. I have mine set at .040

[RoyE]

Ok so I got the new rectifier, but it didn't fix the problem. I am conviced there are multiple problems with this motor, and I first need to fix the fuel problem.

The engine will not idle well, I did this:

- Cleaned all fuel lines
- Cleaned all choke fuel lines
- Carbs are spotless, very clean, float bowls are slightly warped, but from the gasket it seems that the protruding edge pushes nicely into the gasket. The fuel bowls do NOT leak fuel.
- Cleaned all recirculation hoses and fittings. I discovered that the check valve between the lower and upper crankshaft bearing is bad, need to put in a new one.
- Adjusted all floats to spec, two were not not set right.
- Checked timing with timing light, timing is set to spec and not erratic on all four cylinders.
- Checked cylinder head temperature, both were around 150 degrees F.

Now, I experience this problem both on the hose as in the water.

Engine starts very easy, both cold and warm. It will run pretty good when trim is level. On the hose, when trimming all the way down, the engine starts to bog and idle at like 600 rpm. When trimming up (not tilt) the engine will reach 1400 rpm in full trim. It's the same when in the water, but rpm's are somewhat lower due to the backpressure I guess.

What makes my idle so sensitive to trim angle? Can the bad check valve cause this?

[rsukup]

It's normal for an outboard to slow when you drop the trim, especially if the boat is light weight. If it hesitates or boggs check each carb throat for gas spitting back with a white card. Also check for even suction there. If so this is a lean mix and can be caused by gasket or reed problems. I found a lot of answers on Marine Engine.com forums and others.

[RoyE]

We're getting somewhere.

I solved the idle problem, but I don't know what exactly was the cause, because I did two things at once: cleaned the calibration pockets in the throttle bodies (which appeared clean but they are very small so you never know) and replaced all check valves (4 in the intake manifold and the one between the lower and upper crankshaft bearing). If I had to guess I think it was the check valves since it was so sensitive to trim. Runs great now.

As for the problem I started this topic with, I isolated the activation of S.L.O.W. to a bad temp sensor. I also installed another powerpack to test for the running on 3 cylinders while at W.O.T. and the problem hasn't occured since. Only thing left to do is try again with the old powerpack to test if the other powerpack was the solution or the new rectifier already cured the problem.

Bit of a mess since multiple problems occured at the same time, at least I understand this outboard completely now :D

[mn808gade]

lot to be said for CHANGE ONLY ONE THING AT A TIME. easy to say, mostimes - hard to do. just following your progress happy new year-th