1991 225 blowing rectifiers

Hello,
I have a TXEIC, 1991 225, Johnson. for fun I buy tired motors and refurbush them... honed, new rings, all soft goods replaced, new check valves, etc. I am an advanced tinkerer and just short of professional. Ive refurbished about 9 early 90's loopers in the last 3 years. I feel I have more than a clue about these.

Anyway, I just got this one together. It was a touch hard to initially start on the stand but when it started it ran with no problems. I mounted it to the boat and started it in my driveway and she started and ran perfectly without a glitch. Next day I get to the dock to finally get out there and fish...and NOTHING. Not a backfire. Nothing. No spark. Get it home and start parts changing. I have a stock of used parts so I start changing until I find the problem. Basically I had no spark at all. I disconnected the red plug to isolate the motor. I plugged in an in-line spark test light that clips into the spark plug lead, then to the spark plug, thus flashing as current go through the spark plug lead. The only hint of of light I got was at the moment I jumped the starter from the red lead to the yellow/red on the solenoid. It was not the timing of the base/flywheel, it was a wierd initial blip as soon as I would jump the wire, then no lights to follow at all. Strange and unprecedented I though.
So I switched the stator, re assemble, try to start... nothing. same for the timing base, same for the powerpack. So now the motor has a different (all used parts) stator, powerpack and timing base.
I hooked up the rectifier, jumped the starter solenoid and BROADWAY... i got bright, timed light from the test light and a quick sputter or two as if she wanted to start. Great I thought, Its the rectifier. Case solved.
So I then install the original timingbase, stator and powerpack, and install the different (2nd) rectifier. Put it alllll back together, hit the key.... NOTHING! F@(#*$&#(#(@)@((#*#*K!

I get out the ohm meter. the yellow/silver lead of the rectifier to the casing shows nothing when it should show something (according to CDI website). The plain yellow lead shows something (in the 140's i believe). Same thing on both rectifiers. I have a 3rd rectifier which shows numbers (140's) when attached to either yellow lead (red probe on ohm reader) and the black probe to the casing.

So what is blowing my yellow/silver lead to the rectifier? Im assuming I should suspect the stator? Im on my last used rectifier so I have one last shot before It costs me.

Thanks for reading!

Re: 1991 225 blowing rectifiers

Disconnect the yellow wires from stator to regulator, locate the wires so they do not touch ground or flywheel. Now try for spark.

Re: 1991 225 blowing rectifiers

Disconnected yellow stator leads and safely located them, tried to start... no spark

Re: 1991 225 blowing rectifiers

Timer, stator, or power pack one or all three bad. I guess you looked at the magnets in the flywheel and they are all there and tight to flywheel. Wire from pack on correct side of solenoid?

Next step check stator charge coil output voltage, 2 brown wires for port side, 2 brown wires starboard side. Voltage should be 100 or more using a peak reading meter.

Re: 1991 225 blowing rectifiers

Tip: You can use in order to keep testing a Diode Bridge, that you can buy very cheap for any electronics store, and then if you burn some how again, it will be at a fraction of the original OEM or replacement. This will be a 30 or 40 amp diode bridge, square one, with terminals marked ac/ac +/-. connect yellows to ac?s, + to red and - to gnd....that will give you some slack till you?re done testing...even you can provide a heatsink to it and can be used as the OEM...done that on my 235 and still working!!!

Re: 1991 225 blowing rectifiers

Ohm test your stator and see it its within spec's. If your using the older rectifier with the purple wire on them they were bad when made and just waiting to fail. Pull the spark plugs and retest, if you have spark now, you have a starter not spinning fast enough,weak CCA battery or high resistance in battery cables or grounds.

Re: 1991 225 blowing rectifiers

Im totally at my wits end on this one. Thank you all for your advice. I followed quite a bit of it. Ive now been through combinations of 3 power packs, 3 stators, 2 timing bases to now blow my third yellow/silver wire on my 3rd rectifier (no ohm activity from the yellow/silver to ground). The flywheel is reconditioned where I re-epoxied all the magnets. I checked the center magnet on the flywheel and that seems in fine shape. I even cleaned out the 2 cuts in the center magnet thinking maybe they were filled with metal filings and not tripping the base. The most I ever got was spark on the #4, decided to switch the powerpack based on that, didnt have any luck, put back the original powerpack to then lose spark on #4. Yes, the rectifier red lead is bolted to the terminal post on the solenoid on the battery cable side, not the starter cable side.
This would be all different if the motor didnt start and run for me no problem, both on a test stand when I first finished building it, and then on the boat, Turned the key and she fired up without the choke. The next moring at the dock... nothing. I dont know what happened or what is going on. Ive disconnected all the black/yellows as well as the main red plug to isolated it as much as possible. All three stators are generating about 106v from the brown plugs. One book says they should be at least 130v but how can all 3 come in at the same number and be bad? I Im thinking my tester is off a bit. I cant have 3 bad stators (all reading the same), 3 bad timing bases and 3 bad powerpacks.... but like I said it ran initially no problem. Also this is probably my 8th or 9th looper rebulid so ive got at least a clue. Ive spent 2 days trying to figure this out. I also have a 27 series battery run directly thru short leads right next to the motor, isolating my boats' leads incase there was any crap with my boat leads. I have not run a charger or anything foreign during this last round of testing. I even pulled all the plugs and tucked them back into the motor to ground them, then tried starting again to get a higher RPM on the starter. I have also swapped starters for the same reason, but even before all the starter and plug pulling it didnt seem like it wasnt spinning fast enough.:facepalm::facepalm::facepalm:
What do the orange/orange black leads from the stator do? How can you test them? can they be tested on the rectifier side as well? is there any way to disconnect the rectifier completely? Ive tested with the yellows disconnected and not touching anything still no spark. And does anyone know what keeps frying my yellow/silver on the rectifier? It now ohm tests "zero" reading when it had ohm activity in the low 100's before it went in. The plain yellow wire on all 3 rectifiers still tests in the low 100's. Thanks again for all your help i really appreciate all your time.

Re: 1991 225 blowing rectifiers

MEKKAMAZ, I would love to know more about what you did with the diode bridge. is this in place of the rectifier or voltage regulator? Will it save my yellow/silver lead until I figure this out? Do you have a picture of how you set it up? What does it do exactly

Re: 1991 225 blowing rectifiers

The yellow/'silver' is your tach signal. Sure your tach is not shorted out??

Re: 1991 225 blowing rectifiers

I'm pretty sure the grey wire is the tach. The yellows are the charging circuit

Re: 1991 225 blowing rectifiers

Captain Koz said:

I'm pretty sure the grey wire is the tach. The yellows are the charging circuit

Click to expand...

All of the yellows are charge, but the tach takes the signal from the yellow/silver through the regulator. Comes out as Grey(silver) from regulator.

Re: 1991 225 blowing rectifiers

diode bridge is what is used to convert AC to DC (the type we use in ob?s systems), it is an internal diode arrangement . Yes I use it instead of the OEM rectifier, not voltage regulator, as they have different function. Voltage regulator only opens or closes charge circuit in order to keep system from overvoltage conditions. Will take a pic of the actual thing and upload later...

Re: 1991 225 blowing rectifiers

Check the wiring strip where regulator,stator,power coil and tach attach to see if you have a screw to long grounding out rect/reg or under the mounting screw itself. Also make sure that the rect/reg you are using/replacing is the 40 amp one and not the 16 amp. Also make sure your using a "quickstart" timer base with a quickstart pack.

Re: 1991 225 blowing rectifiers

You can leave the regulator disconnected, until you get spark. The orange wires from the stator are the power coil to power the logic in the pack. This should make 30 to 50 peak volts. I will pickup manual tomorrow for the OEM specs, for stator, pack and timer. You can also connect the pack to the shift switch incorrectly and kill the spark.

Re: 1991 225 blowing rectifiers

Awesome, very much appreciated comments and suggestions. Thank you all.
Well, I got it started... but there isnt an easy moral to the story here. I dont know why it started!
Heres how it went. I took a ride down to my trusted Evinrude shop, Outboard Service Corp of Freeport NY. They are awesome. They treat you with respect, and always seem to have all the time in the world for you regardless of what they are doing. Anyway, I ran everything by Mike and Freddy and we talked through a few things. First off, I didnt blow my stators. Basically the yellow/silver lead switched off from use thus the yellow/silver went to no ohms. They told me another test is from red to one yellow at a time, then reverse the ohm tester leads. One way should have ohm activity, the reverse should not. They basically confirmed that the rectifier had nothing to do with my issue.

They basically broke it down to the wiring harness that there must be a short somewhere tricking the motor into thinking the key is off... even though the red plug is disconnected. So I pull the wiring harness and test all the leads for continuity from the red plug to each and every lead end. No breaks. As im testing im pulling and twisting the wires to trigger some break or pause. Nothing. Wiring harness checks out fine. I changed the flywheel and timing base of another motor that ran (timing base number four, flywheel number 2) so I re-connect just the basics of the wiring harness(in interest of time and effort I didnt connect the choke, alarms, etc). Still nothing. I pulled all the plugs and tried again... a hint or spark from a few leads! Changed the powerpack... IGNITION! She roared to life. Awesome!
So the celebration was short lived as I wanted to back track and find the culprit. Flywheel change and test... Ignition. Changed back to the original timingbase and stator... IGNITION. Changed back to the original powerpack... IGNITION. Tested the third stator... IGNITION.

The story may not be over yet. The motor looks like a birdsnest with wires connected for speed not show I have to tuck everything back in and make it pretty again and lets see if it keeps playing peek-aboo with me or if something, somehow triggered.
I am puzzled. I have no clue. I am back to the original flywheel, base, pack and stator (i left the rectifier that was in) and she fires up the second the jump wire hits the solenoid. this chapter of the story points to rpm speed but ive gone through 2 starters and 4 batteries in the process. Starter RPM never seems slow or sluggish. And if it were starter RPM and I got spark with the plugs out, why did it start with the plugs in all of a sudden? Puzzling.

I will report back tomorrow when I have it all put back together and water ready. Im going to have Seatow on speed dial the first few trips

Re: 1991 225 blowing rectifiers

Great news Koz, but I?ll check for a stripped cable grounding near the block, and start with the black/yellow from the pack, that is the kill wire....hope you find the thing before it decide to reappear sometime when you?re out there....cheers!!

....and check all your grounds!!!!!!! that is, disconnect,clean, and reinstall.....

Re: 1991 225 blowing rectifiers

Hello All,
Okay, I had the boat out today and yesterday. She isnt very happy. Ive discovered that my choke may not be fueling even though I can hear the solenoid click. that may have been part of the no starting issue. I have to disconnect the "choke to manifold" hoses and see if any fuel flows out when engaged. Thats not a major problem.
She is not running well at all. Very painful power delivery from idle to mid and then not great up top. I cannot get it past 32 MPH when I should be in the 40's. I have changed the powerpack and I am still getting really rough idle and mid, sluggish power... almost as if I have a dead cylinder but I have even compression (just honed and re-ringed), I definitely can see the rainbow of unburnt fuel in the water so its not a lack of fuel. Its not so bad at higher rpms but its definitely underpowered. I checked all the leads individually with an inline test light and they are all firing but the intensity of each lead is equally erratic. it is not stalling, coughing or sneezing and fires right up as soon as you hit the key. Would I suspect the stator, timing base or rectifier?

Re: 1991 225 blowing rectifiers

couple of questions did you repaint block? what main jets are you running? If you did repaint the block grounds may be painted over on coils etc just a shot

Re: 1991 225 blowing rectifiers

Dehydrated, yes, the block has been painted but I have sanded to bare metal the contact points for the stator, starter, coils, t&t box. Im running #62 mains but I can tell by the spark test light that the electrical isnt happy. I will probably change out the stator, base and rectifier, one at a time to see which one is the issue. I was hoping someone could give me a best bet for which to change first. Its grey area symptoms that could be either. Thanks for your reply I appreciate your time.

Re: 1991 225 blowing rectifiers

go to auto parts store auto zone wherever get an adjustable spark tester set the gap at 7/16 .Hooks between spark plug wire and grounds to block should be stong blue spark test each cylinder best 8.00$ you will spend before spending on parts which may not be bad at all could be as simple as a wire or coil that spark test might narrow it down to if its one or 2 cly or all