MEP004A Voltage Regulator/Exciter BBQ

[McKeelo]

Is this the S9 switch? Is it difficult to repair?

 

[peapvp]

Is this the S9 switch? Is it difficult to repair?

Yes it is.
one repair I did on Shane’s 005

and another thread by another member
both threads deal with the electro mechanical version of S9 vs the electronic version

 

[Guyfang]

Yes, that's the Mechanical S9. It is repairable. If you are going to take it apart, mark on the casing where the lock wired screws are currently placed. That way you do NOT have to readjust the trip speeds. In my experience, a wire or circuit that passes voltage, but no current is a broken wire, that barely makes contact, or a loose wire that just barely makes contact. One of the repeat failures I saw with the mechanical S9 was that the wires inside the S9 cap, would sometimes wear through because of vibrations on the casing, or break off on the cannon plug pins. Also the micro switches sometimes came loose. Sometimes just loose enough not to open/close the switch, and sometimes completely fall off. The electrical S9 was a pluck and chuck. If it wasn't a broken wire on the cannon plug, then we just tossed it. There is a tread someplace here were I listed 7-8 different NSN's that all worked on the gen set. I will try, between Grand Kids invasion and Grampa's bar and grill operation today, to find it.

 

[McKeelo]

Thank you both again for the support. I read the -34 and -24 TM’s all night last night and I’ll be getting n to this sometime today, like Guy says, in between celebrating Mothers Day activities and duties. I’ll keep you posted.

 

[McKeelo]

Alright guys, here’s the update, I took the S9 switch apart even though I didn’t have any parts to replace anything with. Just took it apart for fun. Thank you to member Leedawg for posting the step by step run down. Everything looked ok, if I had a micro switch for s9-1 I would have replaced it. I probed around with the meter and in terminals a,b,and c everything meters the way I expected. The contacts are making and breaking the way they should. Every once in a while the normally closed contacts bounce around on the ohm scale quite a bit and I’m sure that’s the intermittent starter issue.
Now the exciter problem is another story. I found in the TM diagram that the k5 relay coil is terminal 13 on the A5 board and the normally open k5 contact is indeed terminal 14 as mentioned. When I jump 24dc Fromm the breaker to term. 13 I can hear the relay pick and I can meter the dc voltage on and off terminal 14 as intended. However when I start the generator terminal 13 and 14 both go high on start like they should but with S2 in the run position they both stay high +24vdc. I can’t figure out why? From the diagram it looks like the voltage should drop off with S2 in the run position, regardless of what S9-1 n/o and n/c contacts are doing. If I turn S7 on while running it does drop the voltage off A5 term. 13, and 14. I don’t see anything else that would keep the K5 relay coil voltage on with S2 in the run position. Any thoughts?

 

[McKeelo]

Alright guys, here’s the update, I took the S9 switch apart even though I didn’t have any parts to replace anything with. Just took it apart for fun. Thank you to member Leedawg for posting the step by step run down. Everything looked ok, if I had a micro switch for s9-1 I would have replaced it. I probed around with the meter and in terminals a,b,and c everything meters the way I expected. The contacts are making and breaking the way they should. Every once in a while the normally closed contacts bounce around on the ohm scale quite a bit and I’m sure that’s the intermittent starter issue.
Now the exciter problem is another story. I found in the TM diagram that the k5 relay coil is terminal 13 on the A5 board and the normally open k5 contact is indeed terminal 14 as mentioned. When I jump 24dc Fromm the breaker to term. 13 I can hear the relay pick and I can meter the dc voltage on and off terminal 14 as intended. However when I start the generator terminal 13 and 14 both go high on start like they should but with S2 in the run position they both stay high +24vdc. I can’t figure out why? From the diagram it looks like the voltage should drop off with S2 in the run position, regardless of what S9-1 n/o and n/c contacts are doing. If I turn S7 on while running it does drop the voltage off A5 term. 13, and 14. I don’t see anything else that would keep the K5 relay coil voltage on with S2 in the run position. Any thoughts?

I guess the simple thing to do here is connect the manual flash button and move on but this thing is making me crazy now

 

[peapvp]

Alright guys, here’s the update, I took the S9 switch apart even though I didn’t have any parts to replace anything with. Just took it apart for fun. Thank you to member Leedawg for posting the step by step run down. Everything looked ok, if I had a micro switch for s9-1 I would have replaced it. I probed around with the meter and in terminals a,b,and c everything meters the way I expected. The contacts are making and breaking the way they should. Every once in a while the normally closed contacts bounce around on the ohm scale quite a bit and I’m sure that’s the intermittent starter issue.
Now the exciter problem is another story. I found in the TM diagram that the k5 relay coil is terminal 13 on the A5 board and the normally open k5 contact is indeed terminal 14 as mentioned. When I jump 24dc Fromm the breaker to term. 13 I can hear the relay pick and I can meter the dc voltage on and off terminal 14 as intended. However when I start the generator terminal 13 and 14 both go high on start like they should but with S2 in the run position they both stay high +24vdc. I can’t figure out why? From the diagram it looks like the voltage should drop off with S2 in the run position, regardless of what S9-1 n/o and n/c contacts are doing. If I turn S7 on while running it does drop the voltage off A5 term. 13, and 14. I don’t see anything else that would keep the K5 relay coil voltage on with S2 in the run position. Any thoughts?

You have to check the wiring on the S2 switch
The S2 switch is in series with the S9-1 switch and Battle-short Switch S7. S9-1 is closed as long as engine rpm is above 300 or 600 rpm
If you have constant voltage on A5 TB14 then it is either because your S2 switch is bad or someone before you changed the wiring. Check and follow your DC wiring diagram plaque in your Genset door