[speedy_50]

I changed the oil and oil filter. Now I turn the key and the only thing I get is the oil pressure light (can hear the fuel pump), engine will not crank. What did I do ?

 

[speedy_50]

Maybe I could elaborate a little bit. Just bought this from a coworker. Cleaned up the engine with my garden hose (could hardly see the oil drain plug). Tried to start it the other day and the battery was dead, so I pulled the cables off and put the charger on. The brake pedal was frozen to one of the bushings so I got that freed up for the most part. Presently have most of the body parts off the tractor (fender pan, passenger tower side panel, grille and engine side panels). Not sure what any of this has to do with oil pressure. Where is the oil pressure sending unit, maybe I need to start there ?

 

[deaddeere420]

The oil pressure sender is on the adapter for the oil filter. There should be a single wire running down the engine that plugs on the flat tip of the sender.
However from my experience this will not stop the tractor from starting (I have a 88 420 with the Onan P220)

 

[deaddeere420]

I would start with the safety switches
As a diagnostic by pass each one individually
look at the brake switch since you worked there
also the neutral safety switch and the seat switch since the fender pan is off

Also check the back of the ignition switch for corrosion and the ground at the battery box too

Remember once you identify and correct the problem to re-enable the safeties

 

[speedy_50]

John, not sure how I would bypass a safety. Is it just a matter of jumping two connections. How would I check a switch with just one wire going to it ? Will get my meter out tonight and locate the brake and neutral safety and see what I can see. Thank you.

 

[deaddeere420]

The powers that be frown on us discussing bypassing safeties for good reason.
I am not sure how much I am allowed to say
The safety switches will have two wires going to them in a single coupler use a wire to jump between the two.

 

[speedy_50]

Thanks John, sorry about the electrical 101.

 

[deaddeere420]

np we all have to learn