83' 115 hp Mariner 6cyl. No power under load, Electrics?

[Mark Nagel]

OK, the water jacket cover and baffle plate looked fine. Carbs are rebuilt. Compression is 125 +-3 psi on all six cyl. I just started the electrical diagnostics and may have found something. Stator test one of the readings was 5300 (ok range is 5400-6200 ohms). I also found two corroded yellow wires connected to my rectifier going to the stator. I re-wrapped the wires, no change. Any suggestions and do you know were I can find a stator and maybe a rectifier?

BTW, at the launch today, I can get full revs with the motor/prop almost out of the water (low load) when I tilt it down adding load it bogs down right away. Just like if I start with it full in the water, can't get it to rev up.

Mark

 

[CharlieB]

Re: 83' 115 hp Mariner 6cyl. No power under load, Electrics?

You need to test the stator output voltage. Disconnected you must use a DVA Meter however, while running you may be able to use an AC Volt Meter.

Careful, these voltages can bite.

Measure the voltage on each blue and red wire at idle and compare the values to those found in the chart in the CDI Ignition Troubleshooting Guide found thru this link

www.rapair.com

 

[sschefer]

Re: 83' 115 hp Mariner 6cyl. No power under load, Electrics?

Charlie's advice is dead on as usual. The two yellow wires from your stator go to the rectifier which gives you stable DC voltage for your accessories and helps to keep your starting battery charged. Most, but not all, also give trigger voltage to the Tach via a Gray wire. The two yellows from the stator usually go through a terminal block (varies from model to model) and then to the two yellow wires on the rectifier. The rectified output voltage is on the red wires and they are connected to your battery circuit, usually at the starter solenoid.

I should also mention that on some models what might appear to be a terminal block may be the rectifier on some models. The ones I have seen have two yellows and a single red in the middle. Normally, there won't be two addional yellow wires leading from this type of rectifer to another box. The tach signal is sometimes taken from either of the yellow wires.

The other wires comming from the trigger and stator go to your switchbox. These vary slightly for different stators. If you intend on doing further troubleshooting, you shouldn't do so without a complete wiring schematic for your specific engine.

The simple, (minimal tools), test is the resistant check which you have done. This is a preliminary check only and only helps your identify a possible irregularity. You've done this step so, as Charlie states, you now need to purchase a DVM and take the tests to the next level.

However, the DVM test may still not be absolutely conclusive. The final test is to remove the flywheel and check the stator for burn marks and the flywheel for loose magnets. There were two types of magnet installations. The most common to me have been epoxied on but there are some that are screwed on.