sight tube connections

1823 Views 20 Replies 5 Participants Last post by frank 318, Sep 14, 2021

frank 318

Discussion Starter · Jul 30, 2021

i just got a 318. they manual shows a hose going up from the sight tube that mine did not have. there was a clamp around a nipple with rot still clamped. i took it off, and attached a clear hose from the sight tube back to this nipple on the trans. now my pto won't engage. any connection? about to put her on a ramp...thanks for any advice. frank 318

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MDrew

· #2 · Jul 30, 2021

There should not be a connection of any kind between the sight glass and the PTO. Many times the PTO not working relates to a safety switch problem or a bad pto switch or just a blown fuse. For luckier people the plug on either end, at the switch or PTO came loose. The worst is the PTO went bad.
With the key on and the PTO engaged you should have 12 volts at the connection by the PTO. I'd start there. Check the fuses. Spray some contact cleaner in the PTO switch. While you're waiting for that to dry check the connection for the seat switch and the neutral safety switch, just inside the dash, the hydro lever bumps it for starting, not likely your problem.

rwmeyer

· #3 · Jul 30, 2021

Mike is "kinda" correct in that there is no (direct) connection between the pto & site tube. BUT! While connecting site tube to top of hydro, you may disturbed the wiring connector to the seat switch. If tractor will crank, neutral switch is OK, but could still be any of the other problems that Mike mentioned. Another quick note, when checking for voltage at pto plug, someone, or at least 100#, must be on the seat!
Do some checks and report back. Bob

frank 318

Discussion Starter · #4 · Jul 30, 2021

thanks again. so... the sight tube IS supposed to be connected at both ends?...

rwmeyer

· #5 · Jul 30, 2021

Yes, both ends. The bottom connection is what shows the oil level. The top connection is merely a vent. If the top of the tube was plugged, oil would not be able to move into the tube, trapped air would prevent this. If the top tube is open to atmosphere, it could suck in dirt and debris. By connecting to the hydro, the air in the tube & oil is in a closed and clean system. I believe there's another vent in the hydro where the trans oil fill tube connects and this should be kept clean of debris. Bob

frank 318

Discussion Starter · #6 · Jul 31, 2021

without yet checking the top of the sight tube, i talked to my brother-in-law whose tractor it was, and he told me to run the tractor in reverse and engage the pto, and sure enough, it worked... lawn mowed . now for the real work of removing the deck and a top to bottom check over of all systems, lube points, and vents, i'll be back. frank

rwmeyer

· #7 · Aug 1, 2021

WOW !! THAT's a strange one. The 318 does not have an RIO switch and, electrically, doesn't "know" or care about Fwd or Rev... only Neutral for starting. Is this factory original wiring or have "things" been modified? Bob

rydplrs

· #8 · Aug 1, 2021

That sounds like the air gap it to large.

frank 318

Discussion Starter · #9 · Aug 1, 2021

air gap? don't see any weird wiring but it's totally new to me and i haven't really got into it yet, i needed it to work foremost.

rwmeyer

· #10 · Aug 1, 2021

Air gap is with reference to the pto. There are 3 slots on the side of the pto where you insert an .018" feeler gauge with the pto "Off". The nuts with springs under them are turned until you get a light "drag" on the feeler gauge and your air gap is now set at .018". It's not uncommon to go around 2 or 3 times to het the same feel in the 3 slots. Then start engine, engage/disengage pto 2 or 3 times, shut down and check gap again. Bob

Rob R

· #11 · Aug 1, 2021

rwmeyer said:
Air gap is with reference to the pto. There are 3 slots on the side of the pto where you insert an .018" feeler gauge with the pto "Off". The nuts with springs under them are turned until you get a light "drag" on the feeler gauge and your air gap is now set at .018". It's not uncommon to go around 2 or 3 times to het the same feel in the 3 slots. Then start engine, engage/disengage pto 2 or 3 times, shut down and check gap again. Bob

I had intermittent problems with the front/mid PTO not engaging on my 430 (I believe this is the same clutch, if not VERY similar). The problem was the air gap. Easy to adjust with a feeler gauge and wrench (Diesel engine makes it more difficult on the 430 due to lack of space). The Tech service manual has great instructions.

frank 318

Discussion Starter · #12 · Aug 5, 2021

i was so happy to get the operator's manual, parts manual,
and the manual for the deck. but i'm certain that i really need the fos manual and the service (or technical)
manuals. went deere with the numbers, i guess i'm a couple of decades late. maybe a college library? you might guess from the content but i can't get it started along with or because of my earlier problems...the knob on the mule drive came off in my hand as i performed step one in the mower deck manual......

rwmeyer

· #13 · Aug 6, 2021

"but i can't get it started" ???? Last I knew (post #6) you mowed, so what's happening/not happening?
Mule drive knob: You should have a nut behind the adjusting knob that needs to be TIGHT. Also, lube opposite end of stud that goes into clevis. Use oil, not anti-seize, and wipe all excess off of stud... excess lubricant will hold debris and make re-adjustment difficult. Keep us posted. Bob

frank 318

Discussion Starter · #14 · Aug 7, 2021

plug gap was double recommended. now it starts like a dream. i got the deck spinning by driving backwards and hitting pto switch mowed about 50 yards deck stopped turning, and nearly stalled tractor. got it back in the shop...

rwmeyer

· #15 · Aug 7, 2021

Mow again, or at least drive around with pto "On" and blades turning. When deck stops turning and tractor labors, shut down, remove pto to deck belt as quickly as you can, and rotate deck pulley that belt was on. You won't be able to quickly "spin" the pulley, but it should rotate easily by hand. If not, bad bearing(s) in deck. If pulley turns, go up front and try turning the 2 pulleys on the mule drive... they should spin easily. If all pulleys rotate by hand, leave deck belt off, start tractor, turn pto "On" again and drive! Hopefully you have & can use a multimeter! If engine starts to stall/sputter, turn pto "Off", shut down, and disconnect plug on pto. Put meter leads into plug going to pto clutch and read ohms... should be around 4 ohms. If 2.5 or less, clutch is bad. If 3ish, possibly bad charging system.

Do some checks and report findings, and we'll go from there! Bob

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frank 318

Discussion Starter · #16 · Aug 7, 2021

problem was his gap!!!!! Thank you one and all. lawn mowed even tho it practically a lake.... such small adjustments solve big probs! you can all be sure that i'll be back as i learn more and more about this hearty beast.

frank 318

Discussion Starter · #17 · Aug 29, 2021

air gap fixed. mower fully operational. then i stopped tractor to talk to a guy. will not start. pulled plugs put new changed fuel filter and hoses to it and from it. had to push it 300 yards to garage to get away from bugs. i have the rear fender and seat off will i be able to start it without dead man switch?

rwmeyer

· #18 · Aug 29, 2021

Seat switch is an interlock for the pto. If pto switch is "Off", hydro in "Neutral", and brakes set (??), tractor should crank. Start with battery voltage check at battery terminals, then battery cable on starter to ground. MANY possibilities! Bob

frank 318

Discussion Starter · #19 · Aug 29, 2021

tractor cranks.(replaced seat) have spark have fuel have no clue why it won't go....

rwmeyer

· #20 · Aug 29, 2021

You mentioned that you changed plugs, di you gap them? Sometimes new out of the box are not gapped correctly!

Another... REALLY odd-ball... possibility is water in your fuel! You had fuel in the carb bowl when you first started mowing and any condensation in the tank (??) may have been agitated enough to burn. After stopping to talk, water may have settled. Give it a shot of starting fluid, just a small shot! See if it wants to fire. I really can't think of anything else! Bob

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