SA-250 troubles

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I am in the last stage of getting my SA-250 finished up and its giving us fits. We talked to Stumpf Welding today and they faxed us a schematic.  ( but fax and hard to read )....Thank you Stumpf.Helped some but still not solved.The problem is 12 v from the alternator ( took it out and had it checked at a shop today, the regulator was not tested )Per schematic there is a 12 volts that runs from the alternator to the to the starter switch. Fine we had it wrong and have moved the lead on the alternator. When the start button is depressed we have 12 volts. Stop holding the button 12 volts is gone. We have anally checked wiring to the amp meter and between the murphy switch ( relay ) and the murphy valve.  So at the oil pressure sensor , no voltage ( which make sense) as there is no 12  volts unless the button is depressed. No speaking of switches the schematic show a second switch ( wiper type not push ), which is where I think the 12 needs to come from maybe like a ignition switch, but the welder never had one and there is no 2nd switch.So any ideas on where we are going wrong on this, that Murphy valve shuts off fuel so if its not working starts for a min, then runs out of feul.We did bypass the Murphy valve today and ran the diesel for about 45 min to an hour its running good, a final valve readjustment and its ready to go, but the electrical has us stumped.BTW we did not disconnect all the wires to the front panel during rebuild so most of those are exactly the same as they were when we tore it apart for rebuild.
Reply:Update;Rewired the whole loom today, and found a SA-250 Contential diesel diagram I could actually read not a bad fax copy and although the prints aren't the same, they were close enough.Its charging 30 amps on the amp meter, hour meter checks, so its a great start. Still is not switching from low idle to high idle ( actually stuck in high ). The Murphy valve and switch are still NOT working right.Progress but any ideas on the Murphy ( funny name that, like Murphy's law my welder won't work

)And I was so busy I forgot pics. No sheet metal on it yet, but I will remember to snap pics tommorrow.
Reply:Murphy switch blowing fuse, coil on Murphy valve shorted.
Reply:This has been the part from HELL, ordered it weeks ago, thought it was coming by camel across the country, supposed to be delivered yesterday, checked the tracking number and got:DELAYED due to train derailment. Which probably means its part of rubbished scattered over Northern Montana mountainside.AGHHHHH


Reply:not sure if it will help or not,  I've bought a set of Murphy tattletale gauges and tattletale. I have the wiring diagram form of how they are supposed to be  wired up, not sure if this is what you have or not.  if it is let me know and I get it scanned and send you a copy.

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Reply:Wildeyed,Replaced the oil pressure guage and sensor...... brand new, didn't replace the module but have ohmed it out ( its just a relay ) and its switching properly. No the valve is bad, initially it was giving me 68 ohms across the coil which fooled me, but a few taps and jiggling later its a dead short across the coil. And its funny as it worked before I rebuilt the engine, doubly fooled me. But I got on the line with Murphy's tech support and its definately bad. I just need the part to show up, 15 minutes of work, and this should sort it out.Thanks
Reply:Part came in and the problem solved, need a reed switch, sheet metal reassembled and she should be a DONER!!!!!!




Reply:Hobohilton,I was putting the radiator and grill back in my 250 today. 2 L brackets, 6 rubber standoffs on either side of the of the L brackets thru the 3 stucs run down vertically on the shroud. It fits like crap. When I get the shroud holes lineds up into the frame the fan shround is pushing into the alternator belt so it needs to come forward.Is there something basic stupid I am missing on it? I have a drawing and it looks right but something is wrong. I also can't pull the shroud forward. It can't be that hard.
Reply:Well I got back into this mean today, after pondering it over the weekend, and yes it is what I suspected. When the paint and body work was done we replaced the grate in the shroud. The angle supporting the grate was dropped 1/4 " which miss aligns everything. ( I didn't do it but what is done is done ). The fix as I don't want to trash my new paint job is weld on two shims on the front for the front bolts, plug weld the and redrill and tap the to two side holes on both sides ( might not tap I have bolt clearance ). Which will move the shroud forward 3/8 inch, and up about the same.All the other fixes are ugly and damage paint or alter original parts. which I don't want to do.In minor fab mode but that should sort it out.
Reply:Hello Fred,Can you please assist me with my SA-250 Perkins Diesel issue which seems to be what you experienced?
Reply:Hey Bud,hows the SA-250 running ?
Reply:

Originally Posted by SoCalWelder7219

Hello Fred,Can you please assist me with my SA-250 Perkins Diesel issue which seems to be what you experienced?