stator tests bad > Will engine still run?

[scrampbell]

What's up boat gurus? Sorry for the generic question, but I'm curious to know exactly what the stator does. I know it's involved in sending the charge to the power pack.

Here's my specific question... I have a 3 cyl motor (1984 Johnson 70hp) and my stator tested bad on one lead (resistance test). Manual said to test resistance between ground wire and each of the three leads coming out of the stator. Two tested fine, but one tested infinity. So would this cause one cylinder to lose 100% of spark? How does this part of the system work?

Thanks!

 

[Dave1027]

Re: stator tests bad > Will engine still run?

The stator generates all the electric for the boat. That's spark for the plugs and power to recharge the battery. If the stator were bad the motor would not start. Sometimes there are two separate windings, a low and a high speed. You could have a scenario where if the high was bad it would start but not rev up. The trigger is what signals when to spark the plug.

 

[scrampbell]

Re: stator tests bad > Will engine still run?

Thanks for the info Dave. I totally lost spark out on the water and ended up replacing stator after the failed test described above and still didn't have any spark. Tried a spare power pack from my shop and finally got spark at all cylinders.

My theory is/was that the stator ahd been this way for awhile and was causing one cylinder to either drop or run rough and then the powerpack died which is when I totally lost spark. Does this sound plausible?

If it didn't involve pulling the flywheel, I would put the old stator back on and see what happens now.

Can I get your thoughts on it?

EDIT: here's my thread from the repair section http://forums.iboats.com/showthread.php?t=375064
EDIT: In case it's relevent, I also found a couple of coil ground wires that were broken inside the insulation that I fixed when replacing the powerpack.

 

[Dave1027]

Re: stator tests bad > Will engine still run?

My gut feeling is the problem has always been the power pack (is that the switch box?) I don't see how a stator can cause one cyl to drop out. With the stator it's all or none. Bad coil wiring could cause a cyl to drop. How far off was the stator test results?

 

[scrampbell]

Re: stator tests bad > Will engine still run?

Shoot, I'm sorry Dave... I just realized that it was the timer base that I replaced and not the stator. I'm obviously still learning and got these mixed up. Thanks again for the responses. Does it make more sense now that we're talking about the timer base and not the stator?

Sorry again.