8N Oil drain plug leaking

Hotflashjr

Well-known Member
Location
Western MA
I am running a new to me orchard this year and there is a 8N set up with a NH451 5 foot sickle bar mower I am using to mower banks and under tress with. The 8N runs great but after replacing the oil and filter I can't get the oil drain plug to stop leaking. Leaves a puddle between uses. Is this common or am I missing a seal or gasket? I have only ever worked on two cylinder JD's and newer before so this thing is entirely new to me. Any typical maintenance items I should be aware of besides change fluids, grease, etc? Thanks!
 
Are you sure its the oil drain plug? It could also be leaking from the cotter pin in the bell housing which is where the oil leaks out if the rear main seal leaks, which most of them do.
 
There's a gasket on that drain plug as others have said.
There's also a fair chance an old one is stuck to the oil pan
or to the plug. Clean it off if it's there obviously.

Side note, that oil plug shouldn't be just a plug.
There's a big screen on them normally. If yours is missing,
which many are, I would suggest replacing it. YT sells them.
wm_9N6730WG.jpg


Other typical maintenance items that pop into my mind are the
points, especially if it is a front mount distributor; the air cleaner
which is almost always neglected on a Ford; the hydraulic/trans/
rear end fluid - one common sump, 4.5~5 gallons; brakes and
axle seals which leak and soak the brakes; and the steering box.
 
Thanks Royse. There is no screen on the plug and I am positive there was no oring or gasket material anywhere on the plug or oil pan. I checked because I thought it would make sense there was. On my JD's there is usually a copper crush washer on the plug. Bought the new oil filter and a point/condenser/cap kit from the local old NH dealer and he didn't mention anything about the oil plug gasket. Must have had a good laugh at me in my JD shirt when I left on that one.

This is a 1951 8N by serial #8n360277 and I believe it is a side mount distributor. If sitting in the seat the distributor is on the front right of the tractor. Already put in new points, condensor, rotor, and cap with 4 new Autolite plugs. Also washed out the air filter and put in new oil in the cup. All my 2 cylinder JD's have the same set up on the air cleaner and I make a point to servie them regularly when in use. I wondered about the material in the filter though as it looked like it could be easily replaced.

I need a dipstick for the rear end fluid and it is not the best color. Looks a little milky so there is water in it. Saw tractor supply sells Ford transmission oil for ford tractors. I almost grabbed a jug but now I know I will need two jugs and I think that would be the right stuff.

One axle seal I believe was replaced. The brake is nice and tight and dry, the other not so much.

Steering isn't bad, a bit sloppy and it feels like it is in the box/steering column. I greased everything and that helped out a bit but every now and then it gets a bit hard to turn, I hear a small click and things feel good again. I am guessing a rebuild of the steering box/column may be in order down the road?
 
(quoted from post at 13:01:46 05/27/15) I'm curious. Why would there be a filter on a drain plug?

I believe when you install the drain plug, the screen that is on it protects the oil pump pick up tube from getting plugged up.

Henry had a reason for everything he did. Unfortunately some people might not see any reason to fix that screen should it get damaged and just rip the whole thing off.
 
(quoted from post at 16:21:26 05/27/15)
(quoted from post at 13:01:46 05/27/15) I'm curious. Why would there be a filter on a drain plug?

I believe when you install the drain plug, the screen that is on it protects the oil pump pick up tube from getting plugged up.

Henry had a reason for everything he did. Unfortunately some people might not see any reason to fix that screen should it get damaged and just rip the whole thing off.
I agree CaryC, it surrounds the pickup tube and is to screen the oil.
It's easy to see what they did when you try to reinstall one.
 
Came back to add one more thing pertinent to this thread. While ordering parts one day I decided to order a couple of those oil plug gaskets just to have on hand.

When I changed oil the last time, neither of those gaskets would fit over the threads on the plug. I tried screwing it down over the threads but it was just to tight and I knew if I tried any further I would break the gasket.

What I did was use a one inch rotary file in my drill press to file off some of the inside diameter so one of the gaskets finally fit.

There seems to be some thought here that over time some gaskets tend to shrink just sitting on a shelf. Well, I don't know about that. I just know that mine didn't fit as purchased.
 
(quoted from post at 19:11:36 05/27/15) Came back to add one more thing pertinent to this thread. While ordering parts one day I decided to order a couple of those oil plug gaskets just to have on hand.

When I changed oil the last time, neither of those gaskets would fit over the threads on the plug. I tried screwing it down over the threads but it was just to tight and I knew if I tried any further I would break the gasket.

What I did was use a one inch rotary file in my drill press to file off some of the inside diameter so one of the gaskets finally fit.

There seems to be some thought here that over time some gaskets tend to shrink just sitting on a shelf. Well, I don't know about that. I just know that mine didn't fit as purchased.
Maybe they sent you transmission oil fill plug gaskets.
They are not exactly the same as the oil drain plug.
 

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