Motor Help!!??

I've been having this problem with my motor for quite some time now.
I'll start it and let it warm up while sitting in the boat slip, some times it starts easy, sometimes a pain in the rear!

Can sit there with it in N, rev it up and it runs fine, back out,head past no wake area and throttle down and it just bogs down, no power, no RPM's. Can immediately put it in N and revs right back up, put in gear bogs right back down!@#$%

Can go along with it boging and it will start to sputter and come to life, most of the time, or it just dies and its a pain to get going again.

I have changed the plugs, its getting good fire to all 6, rebuilt the carbs, new coils, drained and cleaned entire fuel system,no air leaks, last week had a buddy in the back squeezing primer bulb to make sure it was getting fuel with no effect, finally cleared up and ran like a bat???

Had a guy today say it may be reeds, but he was no boat mechanic. Getting ready to shoot a hole in it and sink it, want to fish not work on boat!

It's a 1990, 150 HP Evenrude 6 cyl

Thanks for any help at all , Jim

Have you checked the fuel pump?

Ignition timing can have that effect on a motor. I think at least some outboards have linkage that changes the timing with the advance of the throttle.

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Originally Posted by dipsydiver

Have you checked the fuel pump?

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I'm suspicious of the fuel pump.

typically, if you pump the bulb and it doesn't help its not the fuel pump. I would check and make sure the timing is advancing as it should. Have someone work the throttle with the engine not running and watch the linkages...there will be one linkage that goes to something under the flywheel...that is where the stator and timer base are...the timer base should move as you increase throttle...there are rollers and linkages that should be free moving under there...make sure its all moving. If you do this to no avail...and you have a nice BLUE spark...that needs to be able to jump about a 3/8" gap (tester)...and you are getting fuel...I think its time for a compression and leakdown test. A low compression engine will do what you are describing...probably what your friend was thinking when he said reeds...but you'll normally get a back fire or such when reeds aren't sealing. Just some stuff to check. Let us know how it goes.

The confusing part is that it will clear up and run like new! Last weekend I ran as much fuel out of it as I could, wife and I rode around in big cicles for 2 hours without as much as a miss ????

Did it just start this?? You may have an air leak somewhere...when you finally get warm it seals off. Maybe an intake leak or something. These are the things that will drive a guy crazy trying to track down. Even a linkage can freeze up until everything gets warm under the cowling. Try to move everthing under there...make sure its all free.

Did it just start this?? If its just getting on plane that is the problem....lugging and bogging down...have you hit something with the prop?? If its always done this I would look at vent holes or a lower pitch prop. Just trying to get it all out there.

What about the lower unit?? Oil look good?? A seizing lower unit can run good when warmed up but bind when cold...for a time until it goes out.

Go have your electronics ALL tested. Less than a 100 bucks at most places. If you have a timing base or stator going bad things like this can happen. If you do not advance timing she will not want to go with much resistance on her. Have them check the powerpacks, stator, timing base, coils, rectifier...all that stuff.

You are getting fuel or it wouldn't run out like you are saying.

My 2 cents... power pack is not working properly.

You have the optical eye ignition system on there and I have seen the power pack do some flaky stuff.

I bet if you check the spark when its hard starting...there is none.

Take and tap the pack while the engine is running and see if you get a response or change in the way the engine is running.

TMD

Marine Doc...when did they change to the optical?? I thought a 90 model was probably still a GT or standard engine?? I know the early 90's fast strike and intruders were HOT!! LOL When did they put the optical ignition in?? Thanks.

I had the same problem on my 125hp. It turned out to be a timing issue. Have someone pull the flywheel and check the timing.

You do not have to pull the flywheel on that engine. Here is the best way to check and set timing I have seen. Its by Joe Reeves over on iboats.com.

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for Johnson/Evinrude


Joe
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(Timing At Cranking Speed 4°)
(J. Reeves)

NOTE: If your engine has the "Fast Start" feature", you must disconnect/eliminate that feature in order to use the following method. The "Fast Start" automatically advances the spark electronically when the engine first starts, dropping it to normal when the engine reaches a certain temperature.

The full spark advance can be adjusted without have the engine running at near full throttle as follows.

To set the timing on that engine, have the s/plugs out, and have the throttle at full, set that timer base under the flywheel tight against the rubber stop on the end of the full spark timer advance stop screw (wire it against that stop if necessary).

Rig a spark tester and have the gap set to 7/16". Hook up the timing light to the #1 plug wire. Crank the engine over and set the spark advance to 4° less than what the engine calls for.

I don't know the full spark advance setting your engine calls for, but to pick a figure, say your engine calls for 28°, set the timing at 24°. The reasoning for the 4° difference is that when the engine is actually running, due to the nature of the solid state ignition componets, the engine gains the extra 4°.

If you set the engine to its true setting at cranking speed, when running it will advance beyond its limit by 4° which will set up pre-ignition causing guaranteed piston damage! You don't want that to take place.

No need to be concerned about the idle timing as that will take care of itself. The main concern is the full advance setting.

Be sure to use your own engines spark advance settings, not the one I picked out of the air here in my notes.
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you can do this with any automotive style timing light. before you do it make for sure that the linkages are advancing timing as they should...all your linkages need to be greased every year. if they hang a little until your engine gets good and warm then they free up...that would be an EASY problem to fix. Keep us informed.

Sorry Scrapper it was an assumption about the ignition. I do not have the software on this comp to verify, you are likely right about the none optical.

I don't think its a timing issue...they don't fix themselves.

That is what leads me to electronic...something cuts out.

TMD

Nothing to be sorry about. I'm kind of a history buff when it comes to those engines. Just really like reading about the history of outboards and where they have been. Was wondering if I might have missed something. LOL. I was just verifiying.

You don't think the advance linkage could loosen up as the engine warms?? I was just trying to think of easy "free" stuff he could check. I HATE grimlins!! lol :mad:

I had exactly the same symptoms you described on a 60hp Evinrude years ago. I finally narrowed it down to the primer bulb. There is a plastic one way check valve in the bulb, and it had come apart. I unhooked the fuel line, pushed the valve in that hooks to the motor with a screwdriver, and tried to pump fuel with the bulb. It would squirt for a little while, and then just trickle. I fooled and messed with it on a trip, finally drove 60 miles to the nearest Wally world and bought a new bulb and solved the problem.

Advance timing could be tested statically...to see if its full advance or breaking down at any time.

The Marine Doctor - A quick video on Static Timing of an Engine

Has a cyl drop test been performed?
The Marine Doctor - Cylinder Drop Test

TMD

had 40hp 3 cyl doing the same thing and the power pack was bad, 1 cyl. wasnt firing.with the engine running took 1 plug wire off at a time.when i pulled one off and no change in the engine traced it to the power pack.thats the shade tree way.

One of my Carb's gasket was leaking and caused mine to do same problem.