TEA-20 gearbox vent hole location?

Hi all:

I picked up a TEA-20 last year. Not sure of exact vintage, it may be a mix of several, and I haven't found a serial number yet. Fergies with the Standard engine are kind of scarce around here, this is the first one I've seen in person.

I threw in new liners & pistons (85mm, 87 wouldn't fit) and got it running; then medical issues kept me from doing any more until now. But I let my brother-in-law use it to mow a few acres, until the hydraulics quit working. Now I'm trying to get the hydraulics back on the job.

I'm really surprised at the amount of dirt in there! I drained and refilled last year; of course it's due again but I really wasn't expecting the layer of mud in the bottom, along with bits of dirt big enough to feel. I've been looking for where the entire gearbox/hydraulic/PTO/rear axle area vents; but so far haven't found anything? Could someone please tell me where to look for the vent(s) ?

I've got the rebuild kit, think I can handle rebuilding the pump (which I'm hoping is the immediate problem or at least most of it). But surely there shouldn't be so much dirt inside, even working a dirty job like mowing.

TIA,
Randall

There really isn't one TR3 , the dipstick at the rear is probably the only exit for air if it needed to vent .
The dirt you have found is really a normal occurrence with tractors that haven't been cleaned out , it never ceases to amaze owners as to just how much is in there . The majority of it is oxide from the inside of the transmission casing , this mixed with moisture from atmospheric condensation creates a gravel like residue that collects at the bottom . Wait until you remove the pto shaft , there is a dead spot adjacent that acts as a trap for a lot of it . I removed an icecream container full from my 1952 TED20 .
The fix is to wash it out with diesel or some other solvent , then change the oil every five years or so . A decent workout will heat the oil and hopefully evaporate any moisture as well .
The pumps are straightforward enough to overhaul , just be aware that there are early versions that used gaskets to seal and later types that used O rings . Later pumps were also fitted with an oscillating plate that helped keep the control valve from sticking , this will most probably be noted in the manual but may not be on yours if it is an early pump .

This is of the nasty stuff that drained out of my 1957 FE35 :shock:

I don't recall seeing a vent. There are enough places for it to breathe, like around the shifter and the rock shaft.

It is impossible to fully clean one without complete disassembly, lots of inaccessible places for years of sludge to hide. It's kinda' the nature of the beast to have a muddy transmission, they don't really care.

Just change the oil a few times, try to keep a good shifter boot on it, store it under cover if possible.

Thanks, guys.

I neglected to mention that I did change the gear oil last year, removed all 3 plugs and cleaned with with solvent. The control valve was stuck (and I broke it getting the pump out), so it was replaced too. What's in there now is definitely dirt, not rust; I even found some small rocks (not rust colored after washing with solvent) and a piece of grass!

My current theory is that the dipstick has been rattling up in operation, and allowing dirt in that way. Is there supposed to be any sort of felt washer in the little cup? Or something around the spigot on the cover? The dipstick has a spring wire on it, but it doesn't touch the hole until the cup is perhaps 3/4" (2cm) away from the spigot.

Another small conundrum, the book says that only TO-30 should have a shield around the relief valve, but there it is. The pump body is the early type, no wiggler fork and gaskets for the side plates. But the side plates also take two different lengths of bolts, which the book says is only for TO-30; so I'm guessing it's been rebuilt before with later replacement parts.

It will be stored indoors eventually, but the shed isn't up yet. B-I-L was going to clear the land this month, but he's still busy working on his own house (and they are still hoping to move in before it snows). Maybe next year

Been away , so a late reply .

There should be a felt washer under the dipstick , also the top should be cupped to sit over the opening , often this cup falls off and the stick just rattles around in the hole .
As far as stones go well I would suspect something else .
My neighbour called me over one day to see why his mower wouldn't start , a quick look into the tank revealed a dozen pebbles and some sand , a visitor's boy had decided to make it '' run better '' !
A friend's TEA showed water in the oil , lots of it , turns out his toddler son had been '' filling the petrol up '' with the garden hose via the spring loaded oil filler cap :shock: