8N lift problems

   / 8N lift problems #1  

R Yow

New member
Joined
Feb 13, 2012
Messages
7
Location
Sanford, NC
Tractor
8N Ford
The lift on my 8N just quit working. I was usia scrape blade and after letting it down it would not raise back up. I pulled the top cover off and took the pump out the bottom. I bought a rebuild kit for the pump and replaced all the valves, springs, pistons, and cam blocks. Nothing seemed to have anything other than normal wear. I also put new rings on the lift cylinder piston. I put it all back together and it still does not work. I pulled the top back off, cranked the tractor up, operated the valve on the pump by hand and get no pressure out of the line to the cylinder. Going crazy, don't know what to do now!!!
R Yow
 
   / 8N lift problems #2  
before you took it all apart, when the pto was turning, and you looke dinto the inspection cover.. what did you see?

soundguy
 
   / 8N lift problems
  • Thread Starter
#3  
sound guy, I didn't see anything. There wasn't any oil dripping down or anything. So I pulled the top cylinder housing and cranked the tractor up. I reached down in the oil and pushed in on the intake valve and no oil came out of the hole feeding the cylinder. I drained the oil and pulled the pump.There was a lot of gasket debri (small pieces) in the bottom. So I thought maybe the pump had sucked up some of that. Everything in the pump looked good nothing was broke or worn out, no stuck valves. But the tractor was bought new by my grandfather and the pump has never been rebuilt. So I rebuilt it, new pistons, cam blocks, valves and everthing. I put the thing back together and still nothing. I pulled the top back off and operated the valve by hand and still no oil.
Thanks for the reply
R Yow
 
   / 8N lift problems #4  
have you loosened the chamber plugs on the top and let her run a bit?

with the intake burried under oil, that pump is generally not a hard starter when it comes to air locking.. though I have seen rare situations where it would..

pistons look ok in their bores?

if still nada.. I'd be tempted to make sure the valves moved and seated correctly.. and then put some 00 grease int he cyls.. or vasolene in t here and reassemble..
 
   / 8N lift problems
  • Thread Starter
#5  
No Soundguy I have not tried that. I've pulled the pump back out now. A guy on another forum told me to check the exhaust valve. When I rebuilt it I couldn't get the exhaust valve out, but I didn't force it. He said he had to tap his out with a punch. Mine worked freely and the spring felt strong so I left it alone. I'm going to try and get it out and double check everything again. I put new pistons in it when I had it out before, and they felt like they had a good fit in the bores but I didn't check the actual clearance. Since I already have it out I'm going to try your idea and put some vasilene on the pistons when i put it back together. I really appreciate the help!
Thanks
R Yow
 
   / 8N lift problems #6  
I bet your clearances are fine onthe pistons.. considering most of em still pump when 60 ys old.. but.. the grease will provide some initial seal in case there are some wear in issues.

post back what ya find.
 
   / 8N lift problems
  • Thread Starter
#7  
Hey soundguy, I got my new gaskets yesterday afternoon. I bolted it all back together, fired it up and the lift finally works. I have'nt put any weight on it yet but I'm sure it will be fine. I don't know why I didn't put anything in that pump. I've built a lot of car engines and I always put oil in the pump during assembly. When you said that about the grease, I said to myself you dummy!!! I'm going to hook up the mower this morning and try her out.
Thanks again for they help.
R Yow
 
   / 8N lift problems #8  
glad to got it.

Tep.. I usually use 0/00 grease or vasolene in pumps when i put em back together.. just helps clearances seating and initial lube.. and prevents air locking if you have a valve that ain't perfect..

soundguy
 
 
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