My motor does not like warm restarts!

[DC20]

So I have taken my new to me boat out for the 5th time. 1999 Johnson, Model J150PXEES
Starts up cold fine, runs great in gear, jumps on plane, goes through long no wake zones fine, gets up to 4900 RPM (seams a bit low, still experimenting with that).
Whenever we stop and fish and go to restart the boat (maybe an hour), it's a hard start. It was even doing the lean sneeze and I kept hitting the key choke, once it's up to operating temp its fine.
I have replaced all the fuel lines and primer bulb up to the motor, new fuel separator, new fuel filter at the motor, new spark plugs (all plugs were a nice tan color).
Should I go ahead and rebuild the carbs?

 

[Joe Reeves]

Re: My motor does not like warm restarts!

Fourty nine hundred (4900) is your top WOT rpm? I don't know exactly what the WOT rpm is on that model but a wild guess is about 6000 rpm. I'm sure some other member will jump in here shortly with the exact figure.

First thing to do is to check the compression which should be in the 100 psi range and even on all cylinders. Is it?

Then, with the spark plugs removed, check the spark which should jump a 7/16" inch gap with a strong blue lightning like flame... a real SNAP! Does it? NOTE: the 7/16" gap is important... checking spark with the spark plugs is a waste of time.

The stator (insulated ring under flywheel)..... Should this component be leaking, dripping a sticky looking substance down upon the flywheel area, this would cause a AC voltage drop to the powerpack when the engine is hot (normal engine running hot range). Should you observe this leaking/dripping scenario of the stator, replace it.

 

[DC20]

Re: My motor does not like warm restarts!

Hey Joe, thanks for the reply.
Compression is all 98 to 100.
I have not done an actual spark test.
I have not noticed any strange leaking substance, motor is pretty clean and has not seen much use.
Are you thinking this is more electrical and perhaps timing instead of a fuel issue?

 

[Joe Reeves]

Re: My motor does not like warm restarts!

No, I'm not leaning one way or the other (ignition/fuel)... just stating the normal trouble shooting route. A process of elimination leading to the cause. Guess work pertaining to compression and spark will lead one down a questionable path.

If compression is as you state, and you have perfect spark (strong blue 7/16" etc), then in all probability, either the throttle linkage is not opening the throttle butterflies fully or a carburetor or two is fouled.

You can check for a fouled carburetor by having the carburetor face plate off, and with the engine running full throttle, stick two fingers into the carburetor throat (acting as a manual choke). If/when you do that procedure on particular carburetor, the rpms increase... you've found an offending fouled carburetor. (Assuming the butterflies are wide open)

 

[DC20]

Re: My motor does not like warm restarts!

Rebuilt all the carbs, I wanted to do that anyway.
Checked the spark, found port side top and bottom sparking intermittently (middle did not look real strong) compared to the other side.
Does not seam like it would be a coil as each side shares one.
Disconnected the stop wire, that's not it.
I guess it's down to the stator or rectifier?

 

[DC20]

Re: My motor does not like warm restarts!

I am trying to follow this guide: http://www.cdielectronics.com/downloads/troubleshooting guide/OMC 6 Cylinder Optical.pdf
It says to swap the stator wires, I don't see how I can do that?
Also there is a big connector with 4 Yellow wires, the wires are a little brown where they go into the connector, like they may have gotten hot, don't know if that's relevant.

 

[DC20]

Re: My motor does not like warm restarts!

Ok, looks like those Yellow wires come from the Rectifier. So I think if I unplug that connector and my spark goes consistent then I have a bad rectifier?

The intermittent spark is approximately every 4 or 5 sparks it misses one.

I'm still not clear witch wires to switch to swap the stator. Is it the small wires that plug into the coil next to the spark plug wire?

 

[DC20]

Re: My motor does not like warm restarts!

I disconnected the yellow wires to the rectifier, no change.
I Pulled the 5 pin connector on the port side, no change.
Could the one side on the coils go bad?

 

[Joe Reeves]

Re: My motor does not like warm restarts!

Seeing as how I retired in 1991 and your engine is a 1999 model, I'm not familiar with the circuitry on that model. Hopefully more knowledageable members will jump in here with the proper answers to your problem.

 

[DC20]

Re: My motor does not like warm restarts!

Did some coil testing:
Ground tab to the Big terminal 286 to 334 Ohms.
Between Small and Big terminals 287 to 327 Ohms.
Spark Plug Wires: 499 to 610 Ohms.

 

[DC20]

Re: My motor does not like warm restarts!

Anyone have any thoughts on this?
I'm thinking it's either the Power Pack or the Stator?
I don't really have the equipment to test any further and can't seam to figure out how to swap sides for the stator.

 

[Chris1956]

Re: My motor does not like warm restarts!

DC, if you just have the warm start problem, then you are in some good company as a lot of us have that issue on those mid-late 90s 60* V motors. Some think it is just vapor lock. I get around the issue by advancing the throttle when warm restarting, and letting her run 30 sec or so. She then behaves normally. If you do find the issue, please post so the rest of us can ride on your coattails.

 

[DC20]

Re: My motor does not like warm restarts!

Turns out the intermitant spark is all the time. It was the warm restarts that got me investigating.
I think I'm going to try to swap the leads that come from the power pack to the coils and switch banks to see what happens.
Other then that I have run out of ideas.

 

[DC20]

Re: My motor does not like warm restarts!

So tonight I did some further testing. I swapped the primary leads coming out of the power pack to the coil. The intermittent spark ( about every 5 sparks it misses 1) then moved to the other bank. I don't know if this proves anything other then to confirm the ignition coils are good.
So I guess the stator, optical eye, or power pack are still in question.

 

[Joe Reeves]

Re: My motor does not like warm restarts!

Just jumping back in for a second... curiousity question.....

The five (5) sparks that you do get as above.... are they strong blue lightning like flame that will jump a 7/16" gap... a real SNAP!?

A weak, erratic spark would normally indicate a failing stator.... are you sure that stator isn't melting/dripping anywhere?

 

[DC20]

Re: My motor does not like warm restarts!

Thanks for your input Joe.
They jump the 7/16 gap but they are not as strong as the other side (but do snap) and you can tell with the time that it misses a spark at intervals.
When the motor is at idle or even at 1200 rpm in a no wake zone you can hear the occasional drop and the motor will shudder a bit.
At a cold start it shakes the motor a 1/2" side by side when it's in the cold start mode.
Once your in the throttle not a single hiccup, goes to 4900 rpm (I know it's low).
This was only my second big outboard and did not realize at first that it shouldn't be doing this.
Any input is greatly appreciated.

 

[DC20]

Re: My motor does not like warm restarts!

I'm thinking about cutting the wires from the stator to the power pack to switch sides as it looks like there are 2 seperate wires that feed the 2 banks.
I'm also thinking about removing the flywheel cover so I can atleast try and see the stator, there sure are alot of bolts for that cover.