JD8650 engine oil pressure

[sketchyjeff]

Hi all, I'm new here.
I have a question about our '84 JD8650. I got it out last week after sitting through the summer since seeding. Did some basic maintenance then ran it all day on the cultivator with no problems. Fired it up the following day and it showed no engine oil pressure. Well, actually, the guage went up to normal then fell back down right away. Shut it down, drained the oil, no chunks or bits, changed the filters, new oil. Tried again and now shows no oil pressure at all. Engine sounds fine at idle I haven't rev'd it up.

Is this maybe a faulty pressure sensor? I've never worked on the pressure sensor on this tractor. It's on the right hand (passenger side for a car) just in front of that side's oil filter? Do I need to blow out the port or do any other stuff if I swap it out? Anything I might be overlooking?
thanks,
j

 

[Mark-Mi]

Screw out the sender and put a manual gauge in place of the sender.

 

[used red MN]

Do I need to blow out the port or do any other stuff if I swap it out?

Hello Jeff welcome to YT! When you remove the sender some oil will drain out of the passages in the engine. No need to blow it out or anything just screw the new one in. On older machines with only one wire, with the key on grounding the terminal on the wire to the engine block would give either a high scale or zero scale reading. The wire ungrounded would give an opposite result. This being a 50 series it probably has a plug on sender and might have two wires which makes the quick check of the dash gauge a bit more complicated.

 

[ss55]

Hi all, I'm new here.
I have a question about our '84 JD8650. I got it out last week after sitting through the summer since seeding. Did some basic maintenance then ran it all day on the cultivator with no problems. Fired it up the following day and it showed no engine oil pressure. Well, actually, the guage went up to normal then fell back down right away. Shut it down, drained the oil, no chunks or bits, changed the filters, new oil. Tried again and now shows no oil pressure at all. Engine sounds fine at idle I haven't rev'd it up.

Is this maybe a faulty pressure sensor? I've never worked on the pressure sensor on this tractor. It's on the right hand (passenger side for a car) just in front of that side's oil filter? Do I need to blow out the port or do any other stuff if I swap it out? Anything I might be overlooking?
thanks,
j

Oil pressure gauge of that era is probably electric. Either a bad sender or a bad gauge are not unheard of. You can test the gauge by applying voltage to the terminals and watch how the gauge moves. Likewise you can use an ohm meter to check if the sender if working properly. The service manual should have the specs for the sender and the gauge responses.

 

[Tx Jim]

Welcome to this forum
I agree with others that states to remove sender & install a new sender. It appears from viewing 8650 parts catalog that the oil sender subs to PN RE208261 but check tractor serial # for correct adapter part #.

 

[sketchyjeff]

great thanks very much
some of the other places i've looked for aftermarket sensors have stuff that looks quite different but this is clearly the same as what's on there now
i'll see about ordering one up and getting a manual guage to confirm while i've got the original one off. it's not in the easiest location to get at behind another pipe
j

 

[sketchyjeff]

this one has a 4-contact quick connect similar to a light duty trailer lights connector.

there seem to be quite a few aftermarket suppliers for this thing at a small fraction of John Deere dealer prices. But not all of them look the same or even similar to what's on there now. I'm thinking it may be best to bite the bullet and buy a green painted one

j