Mep806b challenges

[319cssb]

So the mep806b stopped functioning just as I took possession of it. It turns over but does not start. Starts with ether (for a second) and starts with the IP jumped with 24v . Bought a new speed sensor as the old one only showed some 500mv ~. The new sensor did the same and a sensor I dug out of a mep802 did the same reading. The mep802 has a shorter sensor which is helpful. Installation is still a pain in the dick , but far more manageable than the 806b sensor.

the first sensor I removed had some rust flakes stuck to it. Could it be that the flywheel is so rusty that it messes with the reading of the new sensor?
What to do next?

 

[Light in the Dark]

Do your voltage figures change when you adjust the distance from the face to the flywheel?

 

[319cssb]

Do your voltage figures change when you adjust the distance from the face to the flywheel?

No the highest figure of 500mv ~ is When it just about touches the flywheel. It will get worse by screwing the sensor out.

 

[kloppk]

Be sure your meter is set to AC volts when adjusting the MPU.

 

[319cssb]

Be sure your meter is set to AC volts when adjusting the MPU.

That is why I said it’s 500 mv ~ . (~as in AC ) . It’s a rookie mistake , but thanks for pointing it out

 

[Guyfang]

If the MPU is good, the only way you can not get the right output from it, is not being close enough to the flywheel.

 

[319cssb]

Can someone verify if there is a magnet on the mep806b? Or is there a gap that throws out the signal for the sensor?

 

[Guyfang]

Yes, the MPU has a magnet in it. It counts the flywheel teeth going by it.

 

[319cssb]

Can someone verify if there is a magnet on the mep806b? Or is there a gap that throws out the signal for the sensor?

I should have phrased that better. I meant is there a magnet on the flywheel as well ? Or just the teeth on the flywheel that make the sensor pick up the AC current?
@Guyfang already answered it, but when I read it again. My question didn’t make much sense to me.

 

[319cssb]

I got a new sensor and got it adjusted to 1.5vac but no I noticed that the speed control module has no dc power LED on

 

[jmenende]

Mag pickup should be between 2.3vac and 3vac.

 

[319cssb]

Mag pickup should be between 2.3vac and 3vac.

The TM said 1vac - 1.5vac . But that’s regardless. The speed control has not a DC power LED on.
I think Guy mentioned somewhere that it could take up to 3vac to do anything, but I need to check back with him on that

 

[jmenende]

Disregard the manual. Adjust from 2.3vac to 3vac. 3vac is best. Go slowly using the dead crank cause if you get it too close it will shave of the magnet and ruin the mag pickup. Once you get that done the speed sensor on the govr will light up.

 

[319cssb]

Adjusting to 2.6vac - leads to nothing

 

[319cssb]

Adjusting to 3vac and even 3.4vac does nothing

 

[jmenende]

Do not go over 3vac. You might slip up and ground off the tip. Leave it at 3vac and troubleshoot the next issue. Check the connections to the governor. Contact cleaner is your friend. Make sure you pull the fuse before you spray everything down. Do you have access to the canon plugs behind the control module?

 

[jmenende]

Did you remove the governor before? By looking at the pic, the top left nut is missing. Maybe someone fooled with it before or swapped the governor. Is this unit new to you, have you ever seen it run right?

 

[319cssb]

Do not go over 3vac. You might slip up and ground off the tip. Leave it at 3vac and troubleshoot the next issue. Check the connections to the governor. Contact cleaner is your friend. Make sure you pull the fuse before you spray everything down. Do you have access to the canon plugs behind the control module?

Have you worked on or own a 806b?

 

[jmenende]

Have you worked on or own a 806b?

Yes and yes.

 

[319cssb]

Yes and yes.

I’m confused about your question whether I have access to the cannon plugs behind the control module, if you know this unit , you ought to know the answer.