1987 Johnson 88 SPL running rough (not all cylinders?) Videos included.

[tj06civiclx]

Looking for some help, or direction in where to look...

The motor is a 1987 Johnson 88 SPL. We have been running off of an external gas tank. All of a sudden it felt like it was running on only 3 cyinders...

Got a compression tester from Autozone, tested the compression on the cylinders. 2 tested at about 100, one was about 90, and one was just under 90... I don't know how accurate the tester is (it looked like it has been used quite a few times)...

Anyways, put the boat in the water and ran it. Ran like it was missing a cylinder. Sputtering and would stall.

Johnson 88 misfiring - YouTube

Johnson 88 spl stalls - YouTube

We pulled it out of the water, and went to check the ignition coils, noticed the inner part of the wire (I believe it connects to the power pack) were very corroded and green. We cleaned them up a little bit, and put the boat back in the water. Started it up and it was MUCH better. Still sputtered a little bit

Johnson 88 spl no cover - YouTube

We took it for a spin, and it was running fine. Accelerated fine, drove fine.. Then after a few minutes it went back to sputtering...

Thoughts??? We are thinking we a good cleaning of the wires that go into the ignition coils (or replacing the power packs) and possibly new ignition coils.

We already have a good amount of money into this motor...

 

[tj06civiclx]

Re: 1987 Johnson 88 SPL running rough (not all cylinders?) Videos included.

After reading the service manual (should have read it before) I did not run the engine to normal operating temp before the compression test. I also did not have it at wide open throttle...

Would that make a big difference?

 

[Chinewalker]

Re: 1987 Johnson 88 SPL running rough (not all cylinders?) Videos included.

Out of curiosity - what type of plug wire are you running? Are those solid core wires?

The sneeze & stall points to possible fuel issue. Carbs spotless? MIght be able to use a spray bottle to spray fuel into carb throats individually with motor running, and exhibiting symptoms and see if it picks up.

Most most diagnostics, no, the warm-up shouldn't make a huge difference.

 

[tj06civiclx]

Re: 1987 Johnson 88 SPL running rough (not all cylinders?) Videos included.

The plugs are champion plugs. Not sure about the wires. Both have been recently replaced. We have also recently cleaned up the carbs. They didn't look bad before though.

 

[tj06civiclx]

Re: 1987 Johnson 88 SPL running rough (not all cylinders?) Videos included.

Any other thoughts?

 

[Chinewalker]

Re: 1987 Johnson 88 SPL running rough (not all cylinders?) Videos included.

It's definitely dropping a cylinder or two. Hard to tell whether it's fuel related or ignition related. You've already determined you have possible wiring issues with the pack. Might be time to revisit that...

 

[Daviet]

Re: 1987 Johnson 88 SPL running rough (not all cylinders?) Videos included.

You can use an inductive timing light to check the spark on each cylinder while it is acting up. Might help determine if it is fuel or ignition problem.

 

[Garciah6]

Re: 1987 Johnson 88 SPL running rough (not all cylinders?) Videos included.

I have a 1987 Evinrude 88hp SPL, and mine runs great on the start. Once i stop and start again it go to two cylinders. I change, spark plugs, cables, the power packs and next is the stator and trigger. I am not a mechanic, i am just eleminating options. Will like to know if yours got fix with the power packs.
Thanks

 

[keefallan]

Re: 1987 Johnson 88 SPL running rough (not all cylinders?) Videos included.

I would stay with wiring checks. You need to do an ohm(s) check on the plug wires. Seeing green is not GOOD. That green is probably deeper than what you saw. It sort of creeps in the wiring. Remove the coils and clean all the metal parts and make sure that the mounts on the heads are clean/shiny. You can also check the coils for restistance. After you do all that, then use the timing light if you don't have a spark checker to check for a spark. Let the wires hang while attached to the coil(s) and turn it over. Use the light on each wire. Rebuilding the carbs is not that difficult either.

 

[racso]

What was the problem, did you fix it ?

 

[emdsapmgr]

How does the engine run at WOT? That will tell you a lot about your idle problem. From watching the videos, I'd say the engine has a bad lean sneeze-and that's a carb problem.