CO OP E4

I have what we believe is a 50's era COOP E4 Gas
REcently went to start and noticed that gas was on and leaking out the weep hole of the zenith carb. When gas shut off it bleeds back out the wing nut shut off of the gas just before the bowl. Is the gas not burned up in the line and pressuring back out or is this indication of needle or float problem?

When looking up answers to my questions I began researching serial numbers and found what I once assumed where serial number now learning are likely just parts stamped. I have numbers TG 9426 on left side of rear end, and numbers in 9000's on other locations. Left side of frame below distributor I see numbers 4C 34 26 (C is tough to see c,6,0???)
There's a metal plate on engine 6B230
What years the Tractor?

Yes, it sounds like it's leaking past the needle and seat, possibly just a cleaning will fix it, or the
float is leaking. The leaking from the shut off valve stem can sometimes be fixed by gently tightening the
packing nut. the packing nut can be removed and more packing added, I have used teflon tape and had success.

So these tractors were built by Cockshutt tractor
company in Canada. There are several guys on the
Oliver/Cockshutt forms on Yesterdays Tractor that will
be able to give you all of the answers you are
searching for. And some of these fellas can even
provide you with replacement parts. Scroll down and
repost your questions, and you will receive friendly
accurate advice from guys that know these tractors
very well

Sounds like you have 2 separate problems.

1. The packing on the gas tank valve is leaking. It may just need the nut snugged enough to stop the leak and put some tension on the stem so the valve has some resistance to turning.

If the nut is already tight it may need some additional packing. You can back the nut off the threads, twist some teflon tape into a string, wrap it around the stem and replace the nut. Keep adding tape until the leak is stopped and the stem has some resistance to turning.

2. The leaking carb. Very common for a gravity flow carb to leak gas if the fuel is left on. It should always be turned off when done running for the day.

If the carb begins to drip shortly after turning the gas valve on, the needle valve is not shutting off the gas when the bowl gets full.

Not to be confused with leaking a few drops following a failed start or immediately after shutting the engine off. That is normal. But it should not continue to drip, or black smoke and blubber at idle.

Once it is determined there truly is a flooding situation, here are the typical causes:

Trash under the needle valve. The most common cause. If the tank is contaminated with dirt and debris, or flaking rust, the problem will be ongoing until the tank is cleaned or replaced. Sometimes the needle valve can be flushed by closing the fuel valve and draining the carb (there is a drain plug in the bottom of the bowl), or running the engine until the carb is empty, then reopening the fuel valve.

The needle valve may be defective, the float partially sunk, the float level set too high, the needle seat is loose. Any of theses cases the carb will need to come apart and be repaired. Don't be intimidated by this, the carb is simple and designed to be field serviced. Plenty of how to videos, parts breakdowns, and specs online.

One other thing to check, sometimes when the gas was left on, or a carb is running rich, the engine oil can be contaminated with gas. Check the oil for overfull, feel and smell the oil for gas contamination. If it has been contaminated, it will need to be drained and replaced.

The serial number is stamped on the top edge surface of the tub on the left side. Will read 40-XXXX. Tractor Data or many other listings will tell
you the year. Sometimes just sitting with the gas shut off will cause the bowl gasket or packing to dry out and shrink. It may stop leaking after a
time.