OK Kris, here we go.
We need to see where the L1, IP solenoid has lost its power. We are going to work backwards. This is where I need to put on my instructors hat. So you and anyone having a problem with starting a MEP-004A, MEP-005A, MEP-006A or MEP-007A, or the precise power variants.
So to get started, I introduce the the S9 Over speed switch. What has an over speed switch to do with starting and stopping?
S9-1 contacts do two things. Contacts A&B, (They are closed contacts) are to let the STARTER relay, K3 do its thing. Engage the starter.
So at 298-310 RPM, the A&B contacts open up, to prevent ring gear clash, and S9-1 contacts B&C close and send 24 VDC to the exciter, to light off the Main gen.
S92 contacts are not relevant to your set. Only precise power sets. So we can ignore them.
S9-3 is function is to close contacts F&J, (at 1200-1250 RPM) to tell the A9 fault indicator that there has been a over speed situation. Bingo, light comes on.
S9-3 contacts G&H, in turn open up, telling the L1 IP solenoid to shut off. That way the over speed SHOULD shut down the engine. I am here to tell you, it is possible for it to NOT shut the engine down under the right circumstances.
What we are going to do Kris, is circumvent the S9. To do that, we need to remove the J37 C-Plug from the S9. Then take a paper clip, and bend it straight. Then bend it in a U shape. Insert it in the female pins A&B. That way we can get the engine to turn over. Then, get a second paper clip, and fix it up the same way. Insert it in pins G&H. Then go around to the S2 and start the set. Should it start up, let it run a few seconds, just to let you know its alive. Then shut it down. Don't forget, you do not have over speed protection at this time. ALSO remember, your volt and hertz meter will NOT work, as we are not going to let the B&C contacts close to light off the Exciter.
If this doesn't get the engine to start, we need to go a step farther.
NOTE: any time a 004-007 will NOT crank the engine, the first thing I did was jump the pins J37- A&B. If the starter spins, the S) is at fault.