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8rcob 1985 8 hp electrical problem

In post #20, you mentioned a flywheel key MISSING! How can it escape? I don't understand. Who has been working on this poor little motor?
 
timguy said:
In post #20, you mentioned a flywheel key MISSING! How can it escape? I don't understand. Who has been working on this poor little motor?
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Tim... He/She/It used the terminology "gone" instead of "missing", a term used loosely in many instances which is widely misleading to say the least. Frankly, I doubt strongly that this engine exists after re-reading through 31 posts/replies. If it does, it's time for a qualified shop technician have a go at it as it appears this will go on forever without success.
 
It is now about 70 degrees instead of 30. Close water too.

The motor runs ok at idle and runs normally at high speed, so far. One run about 30 minutes.

But between the two speeds it sounds like a grinding noise. As soon as it accelerates to high it sounds great. Any idea what it might be?

I tested both coils and the coil on top and both looked ok.
 
Took it for another run and it quit a few times.
Maybe that grinding or rattling sound is because is just an old motor.

I will take it for a high speed run tomorrow
 
To recap, it has new fuel line between carb and fuel/water separator. New flywheel key (fits tight),I put about 4 hours on it and still having trouble. Spark jumped 7/16 gap. Ohms tested coils and looked ok. It sometimes runs great at all throttle settings for 40 minutes and than acts like it will quit. Once it sounded like it was missing after cold start. This morning it was bucking after starting, then quit. It wouldn't start so I rowed back. I acts like a key problem again
Looks like a power pack going bad.




8
 
The flywheel key must be aligned properly. The proper positioning is to have it aligned vertically with the engine's driveshaft NOT the crankshaft taper... that is straight Up & Down.

Also, the flywheel nut must be torqued to factory specifications (look it up). To simply tighten the nut with a wrench, breaker bar, whatever, is inviting a sheared key and damage to the flywheel & crankshaft taper.
CS-FW_Key_Align.jpg
 
racerone said:
Factory replacement key must be used.
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Your factual entry is appreciated racer... I tried to edit and enter that bit of knowledge and kept receiving a notice that my 3 line entry/edit had to be over five digits... no way to get around it. Something else in the program to be corrected. So many boaters try to get by with the cheap hardware keys which leads to key shearing and taper damage.
 
I checked and the omc key has a slight mark but looks ok. It is straight up and down with the notch at the top. We torqued it at 45#.

It had a few backfires and kick backs, so I suspected the key.
Looks like the only thing left is the PP.
 
Right.....see post #6 and #8 also. These are problematic at 30 years old especially. Kinda like women. That's when my first wife ran.
 
I put a new cdi pp on and it won't do anything but pop through the exhaust about every 5 pulls. The gas was filtered through 2 coffee filters. The key is good.
 
How much will you sell me that motor for? This is a nightmare. I have one just like it, if I can't fix it, I'll use it for parts. I'll pay for shipping.
 
Okay then, lets fix it.
One of your coils, or plug wires is arcing out at higher speeds and that is because the ignition system puts out stronger spark at higher rpm's. Not an easy problem to detect. I have noticed that the final output coils can arc internally and cease to supply spark to the plugs. They may ohm test okay, but will sting you. "Been there, done that"? NO: "Am here, doing it".
 
The wires in the pp are stretched so tight that when putting the hood on it pulled the plug apart enough to stop the motor so the hood was left off. The wire that holds the plug together left a 1/16" gap. Maybe that could be the problem? I pulled the wire coupler ends inward and that helped. Maybe it was flexing enough to cause a miss. The plug will have to be held higher to keep it level with a plastic tie.

The coils on the 8 are 582508 oa 08t08
The good coils on my 30 hp are 582508 oa 08u16
Two others are 582508 oa 05u15.
Can they substitute? Rub
 
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Get someone to help you . Get a 3/4 drive socket that fits the fly wheel nut and an extension the short one .cut the female drive end off the shorter the extension the better take the plugs out mark with white paint the 30 degree line on the fly wheel as well as the TDC pointer mark. turn the fly wheel so that no 1 piston just starts to go down on the down stroke then connect no1 plug to the timing light put your socket extension into a good geared drilling machine place the socket on and turn the flywheel observe your timing marks as you turn over the power head with the drilling machine when you get them to line up you may need to adjust the screw so that they line up .your primary pickup is adjusted by your throttle screw advance the throttle screw so that the roller is between the marks on the cam on this model. By doing it this way with the drilling machine you can al lso observe your spark on both plugs . trying to do this by using the rope start you will be all day.
 
There aren't any timing Mark's on the flywheel.
There is one on the cam roller where it should be on the line when the throttle plate is just starting to open. This is an 8hp. The coils are on the 30hp motor.
 
Timing can only be done the way i described if you have the type 2 CD flywheel ignition & sensor system , then you have the CD magneto System where the timing is controlled by your points it is very important that your gap is set correctly .
 
From 1984 they came out with Type 2 CD flywheel ignition & sensor there should at least then be one mark on the flywheel to indicate the WOT position which will be 30 degrees.
 
I rerouted the wires so plug has tighter fit. I will test. It tomorrow. The plugs don't fit as tight as I would like but probably ok now.
 
Over the years they have been upgrading as technology improves or at least try to but the things don't seem to last like in the good old days .they 1st came out with the Flywheel magneto system , then they came out with the low tension Flywheel magneto system ,and then there are 2 types of capacitor discharge CD magneto systems. the 8hp came out in 1984 so he has a CD discharge system and it should have at least a mark on the flywheel to indicate the WOT position.
 
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