Seeking advise regarding problem with Farmall Cub

Hi, first time posting, thanking you in advance for advice.
I have a 1948 Farmall Cub that has been sitting under an open shed for 10 years. When we tried to start it found the clutch was stuck, and using the hand crank, we turned the engine to see if engine was stuck.

It turned freely for about 6 time then can to a hard stop. Removed the starter and reversed the engine rotation using the flywheel teeth one full turn and it came to a hard stop again. Tried the a couple more times to turn with crank then it felt real tight at the stop point but kept turning. After 3 revolutions it turn completely free. Replaced points and condenser, cleaned carburetor and it started up and would run for 15 to 30 seconds and stop. After a few times doing this, it suddenly hit a hard stop again.

What is causing this hard stop? Could it be something to do with the stuck clutch? i am not a mechanic and my Brother who works on his own cars but is helping me is not familiar with this type of tractor.

Im gonna say you have valves sticking and you dont need to turn it with the starter until you get them freed up.you also need to put some motor oil in the
spark plug holes to help lube the rings. They can get pretty dry in 10 years. If it were mine I would pull the head and see what each valve is doing and oil
them real good.the oil will not hurt anything. It will smoke a bit when you first crank it after you have freed everything up. Once you get the engine going
then you can work on the clutch. Moisture made the clutch stick and moisture will make it loosen up. Most want agree but I spray water on the clutch
several times and it will break loose!! An old old farmer taught me that a long time ago!

Good luck and have fun figuring it all out. Lots of help here on this site. Im sure others will have helpful information as well.

I don't know if possible in Cub but Mr Mouse builds house in my Farmall A bell housing. If you do manage to get it started it will smoke severely.

The one full turn to a hard stop factor could be carbon being pinned between the cylinder head and piston in the tight area away from the plug. If a stuck valve, it is usually about 2 turns. I would pull the head rather than bend a rod or break a ring. After 10 years, the oil pump needs to be primed before cranking it much. a hex plug by the oil filter when removed will allow oil to be pumped into the system until pressurized. A pump oil can and a bit of small hose will adapt it to the hole. Jim

(quoted from post at 18:39:06 02/14/23) I don't know if possible in Cub but Mr Mouse builds house in my Farmall A bell housing. If you do manage to get it started it will smoke severely.

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Duner Wi, I would have never thought of that and will check it out, Thanks

Thank you, I was not aware of the oil pump needing to be primed.
You may have kept me from burning up my engine. I really appreciate your comments.

What quantity of oil should I pump into the hole near the oil filter?

what ever you plan running in the engine

Happy Dave Welcome
Janicholson is absolutely right. A Farmall cub gear style oil pump will NOT self prime. You will want to do that.
Also, I agree with the others, it sounds like you will want to pull off the cylinder head.

Hello Dave welcome to YT! Get you some type of a
hand pump oil can. I think it will be an 1/8 inch pipe
thread in the block hole. Go to a hardware store and
buy some kind of a cheap brass fitting that will reduce
the hole small enough that the pointed nozzle of the oil
cans pump can be held against to force it in there.
Pump a pint or so in there if it goes fairly easily. If say
somewhere around a half pint goes in and then it
seems like you need to really force it to get more in I
would stop at that point. I would make sure you have
an oil pressure gauge that works. If you have a
readable one on the engine screw it off and hold a
compressed air blower against the gauge port and see
if it will raise the needle. If not I would go to an auto
parts store and buy the cheapest manual gauge they
have. Otherwise in the link is one from YT I would
recommend it is cheap and I am cheap. If you want to
get an actual IH one click the ..Tractor Parts..at the top
and navigate down to the parts for your tractor, there
is a gauge section. I would also recommend putting a
couple tablespoons of oil in each spark plug hole
before running it again. Some of the replies you have
gotten about sticking valves are a little misleading.
That tractor has an L head or valve in block
configuration. When valves in that type of engine stick
what usually happens is the cam lobe pushes them
open and they just stay open. Some of the replies
made suggest that the stuck open valve would come in
contact with a piston. That can only happen on an
overhead valve engine with the valves in the head
directly above the piston. In the case of this engine
once you have turned it two turns from the position it
was during the ..set not running.. period any difficulty
towards turning the engine caused by the valve train is
over. If there are stuck valves they are relying on their
springs to close them again or help from an external
source like you to free them. I would guess lack of oil
..lubrication.. caused the engine to lock. Hopefully this
will be helpful, I will attach a link to the CNHI parts
diagram for your tractor. CNHI is the current name of
the company that owns the ..IH and Farmall.. names at
the moment. The diagram will give you a look at what
is inside. The engine is in the ..Power.. section. If it is
not obvious many parts are no longer available. For a
time IH simply removed part numbers they no longer
sold for these old tractors so a lot of part numbers and
descriptions are not there. Sometimes it helps to
actually web search the part number for the parts that
are difficult to find. Hint, if you have a phone you need
to hold it sideways to see the top navigation arrows.
And if you lose the page just select ..Model.. and type
in Your tractor model, like Farmall - - and Search and it
will come up in the list to click to open. I would not
recommend viewing this site at first on a phone. It has
some quirks or at least that is what I find using it on an
iPhone. One thing it does is the back button causes it
to go back 2 pages not just one.

Lastly send me an email, I will respond with information
to direct you to access to some helpful documents to
use for working on your machine.
Oil gauge

CNHI Farmall Cub online parts catalog

The oil pump prime plug is a 1/8 plug located on the rear left side of the block just below the top of the block.

We buy dead cubs, fix them and
sell them to folks who put them
back to work. 45+ so far. I
wouldn't have tried cranking on
one sitting that long until I had
pulled the spark plugs and poured
some oil in on those cylinders,
then let it soak for several
days. It sat for 10 years,it's
gonna need time to come back from
dead! Valve cover is behind the
carb, it comes off fairly easy,
lots of quality spray lube in there really
helps. I love Free-All or Deep
Creep, they ain't cheap, but they
work. Pull the head as a last
resort, a couple head bolts go in
the water jacket and if rusted
they will break. START WITH
LUBE! Happy to help if you have
any questions! Nothing beats a
Cub!
<img
src=https://www.yesterdaystractors.com/cvphotos/cvphoto147524.jpg
>
Except a barn full !

You can also prime the oil pump
when you change the oil filter.
There is a small hole in the
filter housing, pump it full.

Thank you, We will check this this morning. I think you and others have prevented me from blowing up my engine. Again Thanks.

Thank you, not good with computers, This is very helpful, this is what we will do.

Hi used red MN,
Where is the hole you indicated that we should put a fitting in for the purpose of injecting oil? Is this the hole where the pressure gage screws in at the rear of the oil filter housing? I don't see any other small hole.

Hi K-MO
Regarding your indication of the hole to prime the oil pump by injecting oil into the block on the left rear side of the engine, is that the left side while sitting on the tractor seat? Wasn't sure if you meant sitting on it or facing the tractor from the front.

There is a small hole in the oil filter housing where the oil pressure gage screws in to its housing. Could that be the one to which you are referring? It is on only hole I see near the rear of the engine and would, if sitting on the seat, be on the right side.

Thank you for your help.

On left side when sitting on seat.