Combines 760 starting problems

Deerebines

Guest
Does yours have the murphy switch for the oil pressureIJ We fought one of those for a long time on a 750 with the 354 perkins. Finally bypassed that murphy switch and solved our problem. Just an idea. Good luck.
 

760diehard

Guest
no switch for the oil pressure, but have one for an overheat situation. With the oil switch, do you have to hold it in while startingIJ Thanks
 

Deerebines

Guest
I'm a bit confused. What are you referring to that needs "holding in"IJ
 

geekyfarmer

Guest
Since you're hitting a button to start it, I'll assume that it's a red cab (correct me if I'm wrong!) Does it crank at all, or is there just the click, then nothingIJ If it's not cranking at all, it's not the Murphy system. All the Murphy switch does is cut off the fuel. The motor still cranks, it just won't start. You might check to see if the exciter wire is chewed in half somewhere. It could be shorting out somewhere, causing the amps to fall and the pump to shut off. For some reason, mice love those things. Two cents worth, and you probably got overcharged.
 

760diehard

Guest
with the oil murphy switch, do you have to hold a button in until the engine builds some oil pressureIJ That is what I was referencing. Thanks
 

760diehard

Guest
no, no cranking at all, the click comes when the button is first pushed, but is just a single click not a series like the selenoid is bad or the batter is low. I am thinking like you that I have a voltage drop somewhere and am workign with my local service guy to wire up a switch to give me 12V at the seldnoid instead of running through the various switches, wires etc. It is just getting him here to work on it that is the tough part.
 

Deerebines

Guest
ok, now we got on the same page, no. None of our grey cabs had any kind of a holding button. We cut a piece of wire and bypassed that murphy switch but since re-reading your post I'm more in agreement with GF. That murphy switch wouldn't have anything to do with zero cranking. Usually our murphy switch would allow the combine to start and then die. I hated that "safety" feature on the engine.