The pump makes a slight knocking noise with a hevey load.
The lift arms will leak down without an attachment on them in less than an hour, faster with an attachment.
What should I do to correct this? It is still usable bit is not getting any better.
Thanks,
Philip
Nothing.. sound slike it is working perfectly normal within it's capability with the exception of the sticking.
1, it's a scotch yoke pump.. the more they wear, the more they knock.. heavy loads make em loud. Worry MORE when it stops knocking.
2, 800# or so is hitting the top end for the N. A 6' hog is HUGE.. and LONG .. remember high school physics.. the end of that tail wheel is HOW FAR? from the end of that tractor?
3, leaking down with no load in an hour after shutdown? That's almost bragging time. Many 'worn' lifts leak down in SECONDS or perhaps a minute.. anything that leaks down in less than 5 minutes. It's almost not worth 'fixing' unless you want the practice and have money burning a hole in your posket.
4, the sticking.. which is the only 'real' issue I see.. that's usually caused by dirty gritty oil sticking the control valve. with the round dipstick cover removed there will be an arm hanging down from the top cover that engages a lil slotted control at the pump, and moves fore and aft.. if it sticks, it cannot move fully fore or aft, and in fact the rod may move up and down a bit trying to move the valve fore / aft.
lots of things at play here.
if the oil s dirty, it for sure needs a change.
if doing a change.. might as well get some practice and go for the full meal deal. set aside about 8 hrs for a full top cover and pump r&r
you will need the following:
top and bottom cover gaskets, 3 gaskets under lift cyl, pto flange gasket, and round inspection cover gasket.
cam follower pin.. it's just a short dowel pin.. drill bit stem from an old drill bit even works.. many times they are wore down flat or thru.. it rides on a cam on the cast piece the 3pt rock shaft goes thru.. many times it wears the cam in profile, thus, if you need to build it up with weld, you have a witnes mark.. build up if needed,t hen grind or file to match contour... when repalcing the pin, use a socket to backup the thin stamped metal bracket it is pressed into, and do the same when tapping a new one in.
while pump is dropped pressure wash out the diffy, pto and trans .. ie.. have trans cap off and pto shaft has to be out anyway.. use a garden sprayer loaded with some alcohol from the drug store and a lil mineral spirits or diesel and a bit of atf to spray around in the sumps with drains open to flush out any water after pressure washing. don't get carried away with the washer..
next.. repalce the relief valve screwed into the pump.. may look like a spark plug.. etc.. has a soldered on cap usually.
if the piston is the oem 3 mean ring style, I reccomend using the newer naa style piston with a big fat CNH rubber oring and neophrene backup cup shaped washer.. washer towards the open end of the PISTON.. closed end of the piston goes into the cyl. lightly hone the cyl with a brake hone if it has and scratches or gouges.
don't use any gasket goop on the gaskets .. ( pto flange gasket and inspection cover gaskets *could* get goop if needed.. but you won't need to as they are not holding back pressure ).
when refilling with oil, sump holds about 4.75-5 gallons of either utf fluid, or 90wt gl1/3 gear oil ( napa 65-205 ) or 80w90 gl4/5/MT1 gear oil marked YELLOW METAL SAFE (MT1 )
I&T fo-4 manual has 'cookbook' directions on doing this. need like 2-3 wrenches to do the entire thing..
lay some plastic out on the ground under the tractor to catch all this.
I found that removing the right fender and running board, and swinging the radius rod out of the way on that side helped.
when lowering cover back onto machine after pump is back in.. guide the lil arm hanging down into the slotted control valve on the pump. ps.. that arm hanging down should be straight.. not bowed or bent.
soundguy
