Onan issues

[Blacklock]

I have a BGE spec P. Serail # start L99. It start but dies as soon as let off of the switch. I think I have tested everything correctly but the next step is to check the voltage regulator. Does any have a good way to check it? And am I on the right track? Thanks in advance for any help or support on this issue.

[trackman]

Sounds like the circuit board. It has to keep currant for engine to run

[Blacklock]

I have checked the circuit board following the generator trouble shooting guide by flight systems. It appeared it checked OK.

[94-Newmar]

The next step should have been checking the brushes and slip rings. Did you check the resistance on the slip rings and inspect the brushes and the holder? 90% of the time this is the cause of your problem...

If the brushes are ok, slip rings are clean, ohms test on the slip rings is ok, then here is the voltage regulator test procedure I posted in another thread.... http://www.irv2.com/forums/f54/onan-...ml#post2109495

[Blacklock]

Initially when I started trouble shooting the system the brushes were stuck in the housing. I was positive that was my problem. I worked them over and they are free but it did not fix it. I cleaned the slip rings already and checked the resistance, it is 23.5. I will perform the regulator test you have sent and let you know. Thank you!

[94-Newmar]

Ok. What was the resistance between the brush leads with them installed in the block and the block installed in the stator?

[Blacklock]

I rechecked the stator ring it was 22.5. I reinstalled the brushes and checked from the VR plug unpluged 9&10. It was 23.1. The other readings were:
5-9 .007
7-9 .069
10-9=.007
11-9=.461
12-9=.458
10-5 =.009
5-11=.456
5-12=.465
5-3=.104

I had my dvom on diode setting for the second test. If I understand the readings right I get to purchase a VR now?

[94-Newmar]

Um.. yes you need a VR since 10-5 is not "open" - and it should be completely open.

Good find.....Carry on!

[Blacklock]

Thank you all for your help! Any ideas on a good place to get a good part at a good price?

[94-Newmar]

You're welcome.

According to the Onan parts manual yours is OEM part number 305–0809–01.

This appears to have been superceded by this: Replacement Voltage Regulator for ONAN Emerald, Marquis, Microlite 305-0809-01, 305-0851, 305-0782

Or here: http://www.partsfortechs.com/asapcar...-more-p-2.html

I would call them to verify it's correct for a SPEC P and that the superceding number is correct for the OEM.