1990 Evinrude 150 Drops Cylinder

[brewhaha]

I have been having this trouble since I bought the boat 2 years ago but it has gotten worse. I just now realizing that it is dropping fire to a cylinder when this happens. I will list the history.

After running at low rpms the motor starts to sputter. It will not run over 3500 rpms in gear like this. If I goose the throttle a few times it starts running right again. I do have the same wet plug after I use it on the lake. But, that cylinder fires fine when I start the thing at the dock or on my driveway.

What I have done so far:

Decarbed Motor
Replaced leaky / Cracked VRO pump
Cleaned / Serviced Oil Tank
Rebuilt Carburetors
Replaced fuel check valves on intake, purged and cleaned hoses
New, correct, and properly gapped plugs
New Plug Wires

Running on my driveway it sounds great and fires on all cylinders. Starting out on the water it does fine. The problem starts after the motor is at full operating temp on slow downs and after restarting. It sputters as it does when I pull a plug wire or two while running with muffs.

What I suspect now. The coil packs have cracks. Could they be leaking the spark out after the engine compartment warms and the rubber gets soft. Should I replace them? They ohm out good. If I get new ones is there a difference in Mallory, Sierra, or CDI besides the price?
Also, the in wires to the coil packs from the power pack have small boots. They are a little cracked. Can I get those? Would the power pack starting to go bad cause the problem I am having? Also, I think I may need to pull my flywheel and clean the stator and timer base. Does that sound like overkill? If I pull the flywheel, do I have to put it back in the same exact spot on the shaft, or is the shaft keyed so I can?t put it back wrong?

 

[CharlieB]

Re: 1990 Evinrude 150 Drops Cylinder

K.I.S.S.

Start with the coils.

Switch them from one side to the other, run it and see if the problems also switches sides.

 

[emdsapmgr]

Re: 1990 Evinrude 150 Drops Cylinder

I'd check spark on all 6 wires with an inductive timing light when it starts to miss. You need to know which wire(s) is/are misfiring and go from there. Once you know where the problem is, then switch coils as was mentioned. Ignition problems tend to show up once the electrical components heat up to normal operating temps.

 

[brewhaha]

Re: 1990 Evinrude 150 Drops Cylinder

New Info:
I ran the motor on muffs for a few minutes then I let it sit (in an attempt for the temperature in the engine compartment to equalize as this problem occurs after the engine is warm.) All six cylinders were firing when I first started. On the second startup the lower two cylinders on the port side would not fire. I moved the coils and they still would not fire. What should I look at next? This is getting expensive, I am glad I didn?t just throw new coils at it like I started to.

 

[emdsapmgr]

Re: 1990 Evinrude 150 Drops Cylinder

If you have the factory service manual, there are specific tests/checks to be done on the remaining ignition components: power pack, the stator and the timer base. You'll need a special peak-reading voltmeter and a Stevens adapter box is handy for testing. You are getting into expensive components now, so testing is worthwhile. Percentage odds would have you look at the power pack first. If you don't fancy yourself as an electrician, you may want to have a dealer look at it.

 

[brewhaha]

Re: 1990 Evinrude 150 Drops Cylinder

Emdsapmgr, thanks so much for the input. I am an electrician but my fluke reads RMS and I don?t own the service manual. I do have access to a peak to peak meter though i don't know what a stevens adapter box is. I know that when I take it out, I put a full charge on the cranking battery the night before. It does not start missing until I stop a few times, fish, then run it some more. This leads me to suspect the stator but I am new to being a shade tree marine motor mechanic so I am not sure. From what I have read in these forums the power pack normally is the culprit. I don?t own the service manual I may have to invest in it before putting more money in parts. If anybody can post some specific tests to rule out the stator, the timer base or the power pack that would really help me out. I am too stubborn to take her to a dealer (and poor!). I will most likely invest in the manual and continue to lean own you guys for further advice. Thanks for all that you guys have turned me on to so far. Especially you TRASHDADDY, I am dying for your response to this thread. You are always right on the money. Thanks to everyone.

 

[jonesg]

Re: 1990 Evinrude 150 Drops Cylinder

Heres Bill Kelly's troubleshooting guide, covers most makes,you obviously want the section for Johnson.

http://www.maxrules.com/cdi/TroubleshootingGuide.pdf

BTW, any sign of cracked coils are shot, they need changing whether theres another problem or not. Looks like all the ignition system is original, might be time to go through it all.

Last yr I installed a Sierra power pack, cost $150 and works great, I lost spark on all port side plugs.

And get a factory service manual.
www.outboardbooks.com

 

[emdsapmgr]

Re: 1990 Evinrude 150 Drops Cylinder

Ken Cook is the original publisher of the OMC manuals. Good outfit. If you call them, ask them whether the manual you will be getting is in color or just a black and white photocopy of the original. The wiring diagrams really need to be in color.

 

[brewhaha]

Re: 1990 Evinrude 150 Drops Cylinder

A few more questions. Again, thanks so much for the info.

1] How are the cylinder ?banks? divided up? Are the port side lower two cylinders a bank?

2] Is it possible that the cracked original coil packs could mess up the power pack?

The guy I bought it from had to replace it once. If that is possible I am going to replace the power pack as well as the coil packs.

 

[emdsapmgr]

Re: 1990 Evinrude 150 Drops Cylinder

Usually, the bank refers to the port or starboard cylinders. In older days, the ignition had a separate power pack for each bank and there is a separate thermostat for each bank. The coils are generally pretty reliable. I'd consider replacing them if they won't generate a spark. You can swap them between cylinders and see if you get running differences, then decide on each, individually.

 

[brewhaha]

Re: 1990 Evinrude 150 Drops Cylinder

Update

I have ohmed out the CDI power pack using the information I found in the troubleshooting guide of their web site. It checked well. I also ohmed out the stator and found that to check out good as well. Everything under the flywheel looks to be original equipment. I have read several posts with similar problem and one that said a new timer base fixed it (the others didn't list a solution). There is no real check for this without a peak reading volt meter or oscilloscope (that I could find). Anyhow I decided to go with a new timer base and new ignition coil packs. I will pull the flywheel this weekend. I?ll keep the forum posted.

 

[CharlieB]

Re: 1990 Evinrude 150 Drops Cylinder

Timer base contains three triggers, each trigger fires two cyl's, one port and one starboard.

Two cyl's on the SAME bank is NOT a trigger issue.

The stator charges the ignition pack, some models have both low and high speed windings, as well as charging system windings.

A stator will not drop individual cyl's. (Except on a Merc w/CDI coils)

Swapping coils had no effect, it is not the coils.

All that is left is the ignition pack.

 

[brewhaha]

Re: 1990 Evinrude 150 Drops Cylinder

CharlieB, that sounds like some good deductive reasoning to me. Much better that mine. I was able to change my order. I am still going to go with new coils as mine are all cracked up but I am going to change the power pack instead of the timer base. I am still going to pull the flywheel today and clean everything up. I would like to check those magnets in there as well. I will let you know how it turns out sometime next week when I get the PP. Thanks for your help.

 

[jonesg]

Re: 1990 Evinrude 150 Drops Cylinder

CharlieB, that sounds like some good deductive reasoning to me. Much better that mine. I was able to change my order. I am still going to go with new coils as mine are all cracked up but I am going to change the power pack instead of the timer base. I am still going to pull the flywheel today and clean everything up. I would like to check those magnets in there as well. I will let you know how it turns out sometime next week when I get the PP. Thanks for your help.

Whilst you're waiting for parts, maybe go to ratshack and get 3 cheap components to make your own DVA adapter, a bit of solder and plugs to fit your meter.
Resistor, capacitor and a diode is all it uses.
I think they work better with analog meters, needle rather than digital.
Its an interesting simple project.
Then you can test all the other expensive bits.

http://forums.iboats.com/showthread.php?t=299903&highlight=dva

 

[cdoliver]

Re: 1990 Evinrude 150 Drops Cylinder

I'm sure you have made sure all of the grounds are good on the coils, the connections are good inside the boots and there are no wires rubbing on the flywheel. These are cheap checks.

 

[brewhaha]

Re: 1990 Evinrude 150 Drops Cylinder

My Stator, Oh my Stator!!!

Well, I pulled my fly wheel yesterday and figured out two things. It?s not near the trouble I thought it would be and there is some shigidy going on with my stator. There are two large coils on one side, and one large coil on the other side and then the other 6 windings of course. The two large coils have a significant amount of black stuff on them and the all of the pick up points (if that is what they are called) were corroded. Could this be causing my problem? It cleaned up good with some electrical component cleaner and a scouring pad. Should I give it a little die electric grease (to prevent corrosion and rust) then see how it runs or should I just bite the bullet and get a new stator? It still ohm?s out good, and after cleaning it looks good. Also, the fly wheel key has a groove in both sides, is this normal? Should I put a new one in there? And last but not least, can somebody help me out with the torque spec for the fly wheel nut?

 

[emdsapmgr]

Re: 1990 Evinrude 150 Drops Cylinder

140-145 lbs on the flywheel nut. I'd opt for a new flywheel key. You did not mention whether this is a 9 amp charging system or a 35 amp system-found on the GT/XP models. You are getting into some high priced items, in the stator, timer base or power pack. I'd make sure the diagnosis points to the correct part before ordering.

 

[brewhaha]

Re: 1990 Evinrude 150 Drops Cylinder

It?s the 35 amp system. Thanks for the torque spec.
This is a picture of the stator before I took it off and cleaned it. Those charging coils have been heating up and leaking some black stuff. My theory is that when the engine comes up to normal temperature those coils heat up and start oozing. The laminate is melting off and its most likely just a matter of time before it fails completely. It?s probably not charging the cap in the power pack enough to fire all the cylinders on that side of the motor. Thus, I get my intermittent spark problem. I am a beginner at boat motor but I do electrical everyday so I think I am going to go with the new stator at this point. I would value any feedback from you guys on this. You have been helping a ton. I got a new key today, my new coils came in also, and a new power pack (that I am going to keep on standby, I think the stator is the whole problem). Hell, the only thing really left after that is the timer base! As I understand it that would cause two cylinders on different banks to drop.

 

[brewhaha]

Re: 1990 Evinrude 150 Drops Cylinder


Not the Stator, Not the Power Pack, and Not the Ignition Coils.
Replaced all, same problem
This Tread is dead. It's two long. Starting over

 

[brewhaha]

Re: 1990 Evinrude 150 Drops Cylinder

Well, I changed the timer base last night and it ran good on the water hose so I took her to the lake this morning. In a word, SMOOOOOOOOOOOOOOTHHHHHHH!!!!!! It ran great, smooth as a kitten on idle and like a rocket at WOT. The timer base was the problem the entire time but it has a new ignition system now because that was the last thing I replaced. That?s ok though, at least I have spare parts for the next time and peace mind when turn that key on the water.