1985 85 hp loss of power, no misfire

ammermanfam

Seaman
Joined
Jun 22, 2009
Messages
50
My last trip out,after 10 minutes of running the engine lost a bulk of power. It wasn't misfiring like when I had a stator wire burn through years ago, just couldn't get above 2500 rpms. After sitting for a while it would run fine for a while then same situation. I am currently about to test stator and trigger per cdi instructions and am replacing rectifier with voltage regulator as prescribed on this forum. While removing rectifier I discovered intermittent connection on the black ground wire. Can this be part of loss of power issue? Will post ohm readings from stator and trigger when finished
 

ammermanfam

Seaman
Joined
Jun 22, 2009
Messages
50
Stator ohms yellow to blue same connector 1000

Blue to second connector yellow 600

All lines to engine block 2000
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
18,037
Test the over heat system. Might be getting hot??
Key on, ground the orange lead at the buss bar.
That should make the alarm sound off.
The alarm is small and can be hardly heard when the motor runs.
I have a heat gun to test the temps. $16 Amazon(years ago)
 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,909
Stator ohms yellow to blue same connector 1000

Blue to second connector yellow 600

All lines to engine block 2000
If the stator is still of the original the acceptable range for the stator charge coil resistance is 680-800 ohms between the bl/y pairs (2 pairs). The 45 ohms on the trigger set wires of 45 is acceptable although technically it is supposed to be 48-52 ohms between each pair of wires. Double check your stator charge coil readings and just to be sure it is correct, disconnect at least one of the wires in each pair. The insulation resistance, wires to ground of 2K ohms is also acceptable.
 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,909
You will need to check with CDI troubleshooting for the proper ohm ranges for their stator. As for the 2K wires to ground, that needs to be corrected that it is not an acceptable reading for wire insulation resistance. The minimum should be no less than 500K ohms or half a megaohm. This is with the presumption that all wires are disconnected and lifted off the ground potential.
 

Jiggz

Captain
Joined
Oct 23, 2009
Messages
3,909
With the motor not misfiring but will not go beyond 2500 RPM, personally I don't think this is electrically caused but more by fuel and maybe cable/throttle control related. I could be wrong but I'd check on this before delving any further with the electrical side.
 

ammermanfam

Seaman
Joined
Jun 22, 2009
Messages
50
With the motor not misfiring but will not go beyond 2500 RPM, personally I don't think this is electrically caused but more by fuel and maybe cable/throttle control related. I could be wrong but I'd check on this before delving any further with the electrical side.
Finally got a chance to get back to work on motor. At your advice I inspected fuel system and everything appears intact including diaphragm. Only thing I have not done is a visual of inside of tank, however,I upgraded my multimeter to a nice Klein model and got vastly different results from the tired old analog one I had been using. The first pair of blue and yellow that feed the module for 1 and 2 were at 1.6k ohms. Yellow to ground was 2k and the blue to ground was 111k ohms
The second set was at 600 ohms between the pair and 2.22m ohms to ground.

Could the heat from operation exacerbate the situation of what appears to be an already compromised circuit on stator adding to the randomness of it?
 

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