Fixed some things and found a new symptom that I overlooked. New help needed please

[A2M2]

Hi guys, I have cooled down a bit and thanks to procraftguy, I went back out today to tackle it again.
'84 85hp
I replaced the ground ring terinals on every single connection, added a jumper wire to each coil pack connecting each back to the jumper to the block. I also added a #10 ground jumper from there, around to the system ground lug back to the battery.

It has great spark now on all three cylinders again. I put in gear and checked again, and all seemed good. I didn't want to over-rev on the muffs, so I put it into fast idle. When the throttle arm reached almost WOT, it cut out and I lost #3 spark. I started playing with the lever, and there is a "spot" where it dies. Forward towards WOT, it cuts, bring it back a titch, and it picks right up. It is definitely electrical in nature. I can totally control the failure with the lever. It requires about 1" travel in the lever, which due to slop translates to less than 1/4" travel of the roller arm.

Question is- where do I start looking? Is there anything actually in the throttle lever? (I hear a faint clicking near the suspect area when I cycle the lever with no motor noise). Should I be looking there, or in the powerhead? I did try and search, but couldn't really find anything matching this.

Thanks again everyone!

 

[pnwboat]

Re: Fixed some things and found a new symptom that I overlooked. New help needed plea

Take a look at the wires that come out from under the flywheel. The ignition trigger ring and the wires from the trigger under the flywheel move back and forth with the throttle. Look for wires that are frayed from rubbing on the flywheel, or on the block. Have someone move the throttle back and forth while you observe the tower shaft on the side of the motor move and the wires on the trigger and stator.

 

[Jiggz]

Re: Fixed some things and found a new symptom that I overlooked. New help needed plea

I agree with PNW's diagnosis. In addition, you can also do a resistance reading on one of each trigger wires to ground at the point where the lever turns off the engine (leave the lever at this position and then take the ground reading). There should be no continuity between ground and any of the trigger wires. If there is low resistance, then that's what is causing your shut downs.

 

[A2M2]

Re: Fixed some things and found a new symptom that I overlooked. New help needed plea

EUREKA!!
Had to go buy a puller, and fortunately, had much better luck than some I've read about. Got the flywheel off with no trouble, stator off and it looks beautiful. I'm guessing someone has replaced it along the way.

Pulled the trigger out and-

For the time being, I was able to dig the potting mix out far enough to strip what was left of the wire. I carefully soldered the wire back on and sealed it with a piece of shrink tube. I'm sure someday, I'll need to go ahead and replace the trigger, but for now, it runs like a new boat! I still only have muffs, but this time, I'm super confident! It's quite a haul to the lake to test, so it'll be next weekend at the earliest, but I'll report back.
With the discovery of Standard Magneto, I'll probably pick up a trigger to have on hand. I'm sure they'll only go up in price in the future, lol.
Thanks guys!!!!! I'll be sure to keep you posted

 

[pnwboat]

Re: Fixed some things and found a new symptom that I overlooked. New help needed plea

Keeping our fingers crossed! Good luck!

 

[Jiggz]

Re: Fixed some things and found a new symptom that I overlooked. New help needed plea

Good on ya. Personally, that trigger can still be revived if properly rewired and insulated. In addition to the soldering and shrink tubing the white/green wire you might as well re-insulate both wires with an overlapping electrical type and then shrink tubing it. And then finally, use some non-conductive epoxy to bury both wires permanently.

 

[procraftguy]

Re: Fixed some things and found a new symptom that I overlooked. New help needed plea

Hope its all fixed good luck that trigger will do fine if u do as jiggs said it will be as good if not better then new happy boating

 

[A2M2]

Re: Fixed some things and found a new symptom that I overlooked. New help needed plea

Happy Dance... Ends in a tow back to the dock!
Took her out in the bay today, and it FINALLY ran like it should! We zipped out to a neighboring island, had a little lunch and played around. I couldn't have been more excited.

THEN- oh the horror! Power drops off quickly followed by a horrible hi pitched screach and phhhllllttttt! Done seized

Had to get towed back to the ramp by some nice Canadian folks. I pulled the plugs as soon as I got home and squirted a mix of ATF/ acetone that I regularly use for penetrating oil. A little gentle wiggling of the flywheel nut and it freed right up. I hooked up the muffs and flushed the salt water out. It seems to run just fine still, so I'll get right on starting the impeller and thermostat changed

 

[Jiggz]

Re: Fixed some things and found a new symptom that I overlooked. New help needed plea

Not to be critical, but with these motors, you always want to make sure you check and double check two things everytime . . . cooling water and proper lubrication (oil-gas mix). After an overheat and worse yet after a seize . . . do a compression check.

 

[A2M2]

Re: Fixed some things and found a new symptom that I overlooked. New help needed plea

Thanks, and please don't worry about being critical! I knew I didn't need to worry about the fuel as everything was checked fifty times trying to solve the running problem. Cooling system was likely in that condition where "been runnin' great for years!". Running short distances on small lakes. It may have gone many more years like that. Out in the bay though, 45 min straight run, and it didn't fare so well.

Compression test, and a peek with the bore-scope are at the top of the list for this week.

 

[dan4081]

Re: Fixed some things and found a new symptom that I overlooked. New help needed plea

Best thing I (well, actually my brother) ever did was add a telltale to my force 85.
Its a nice feeling to look back at the motor and see water peeing out the telltale so you always know when the impeller is working.

Easy and inexpensive....Should be added to your to-do list.

 

[A2M2]

Re: Fixed some things and found a new symptom that I overlooked. New help needed plea

Thanks everyone! A telltale and an LED idiot light are both on the list!
Good news, bore scope and compression test came back positive! It looks just fine in there and I got 140, 138, and 140 !

I think I'll go buy a couple lotto tickets!

 

[pnwboat]

Re: Fixed some things and found a new symptom that I overlooked. New help needed plea

Ouch, are you sure the cause for the lock up was the pistons or rings? Once you get it fired back up, listen closely for any unusual knocking sounds. I've had the top crank shaft bearing fail and sounded similar to what you're experiencing.

 

[A2M2]

Re: Fixed some things and found a new symptom that I overlooked. New help needed plea

Ouch, are you sure the cause for the lock up was the pistons or rings? Once you get it fired back up, listen closely for any unusual knocking sounds. I've had the top crank shaft bearing fail and sounded similar to what you're experiencing.

Hmmm... Don't like the sound of that! I never did hear the buzzer, but I've read here that people miss it often with other noises. I have run it several times for short periods, and sure haven't heard anything unusual, but I wouldn't really know what I would be hearing. What is involved in checking and replacing that bearing? Full teardown?

Thanks

 

[Jiggz]

Re: Fixed some things and found a new symptom that I overlooked. New help needed plea

PNW's comment is more of a precaution rather than a diagnosis for now. I'll say remove all plugs and this time using a mechanic's stethoscope listen for low slopping or slapping sound while turning the flywheel back and forth. Any play on the crankshaft bearings (rod bearings) will make slopping/slapping sound. If there is no slapping or slopping sound you are most likely good to go. If there is slapping sound then you can start thinking about localizing it and hopefully it's just in the rod journal rather than the main support bearings.

 

[procraftguy]

Re: Fixed some things and found a new symptom that I overlooked. New help needed plea

Yes a full tear down would be involved go to a parts sight and look at diagram of crank shaft and pistons it will show u were its at does sound probable thats what it is but if so u should be able to hear it

 

[A2M2]

Re: Fixed some things and found a new symptom that I overlooked. New help needed plea

Ok- update time. I bought a stethoscope and did my best to try to hear something. I've never done it, so I'm pretty much guessing here. I pulled the plugs and while turning the flywheel by hand, poked around all over the outside, and inside on the piston tops. Heard some stuff, but nothing alarming. Then with the probe on a piston top, and just wiggling the flywheel maybe 1/8- 1/4" back and forth, I hear a kind of sucking sound. Hard to describe, but I'm afraid I have to lean towards Jiggz' description of "sloppy". For some frame of reference, I'm in the middle of restoring a Suzuki GS550 for my wife, which I happen to have the valve cover off and the plugs out. I put the scope on a piston top and wiggled the crank back and forth and heard absolute silence.
I'm thinking my luck may have run out again?? What's the next logical step here? With my new solid understanding of this ignition system, and the compression numbers I have, I think I should save this motor, right? How difficult of a job is the bearings? Costs involved? Parts availability? Etc, etc...
Thanks again for putting up with me guys!

 

[Jiggz]

Re: Fixed some things and found a new symptom that I overlooked. New help needed plea

The "sloppy" sound should be metallic sound since it is actually a play in the bearing journals. Personally, if it is not metallic in nature and there is no play with the crankshaft (horizontally and vertically), I will put it together and ran in idle while listening very closely. Any knocking sound immediately shut it down. Then it is time to open the head and the intakes to do further inspections.

 

[A2M2]

Re: Fixed some things and found a new symptom that I overlooked. New help needed plea

Thanks,
I'll fir it this weekend and listen with the scope a little closer

 

[A2M2]

Re: Fixed some things and found a new symptom that I overlooked. New help needed plea

Well- I'm an idiot! But I solved my mystery

I started pulling things apart again, and looky what I found-

I guess I didn't get the stator mounting screws tightened down, and one backed out. I think now I know where the screeching was coming from! After spinning it's way into the flywheel, the head of the screw finally broke. The head of the screw had jammed in between the flywheel and stator, probably causing the lockup. Fortunately there's no more than a couple of small scrapes and nicks on the plates of the stator. Nothing on the windings!
I continued and pulled the trigger mount/bearing cover to ispect the top crank bearing. All was in great shape underneath! I even listed close with my new stethoscope! Lol. Cleaned up and re-sealed it. I'll get the screw replaced, clean up the flywheel a bit, and I'm good to go!