Hole in engine block...

[Leewebb7]

poking around in my new to me 1951 cub I took the side cover off...and found what appears to be a hole. looks like its located behind the front cover.. The tractor does not run , I just pushed it off the trailer yesterday...

[Dale Finch]

I commented on your introduction post... I'm pretty sure that is just the way the block was cast.

[SONNY]

rather odd to see that in there! are there any pieces laying around the hole? -- or in the oil? drain the oil and screen it. Might find something that way.

[Leewebb7]

I didnt see any peices laying around ....the oil on stick the looks new and clean but that doesnt mean there might not be something ( a piece) in the bottom of the pan...when I get a chance ill drain it and strain it...im tinkering on this in my backyard...its hard to tinker when its cold and windy lol

[Bill V in Md]

That opening is in the front crankcase wall of the engine casting. Attached is a photo showing that opening. It is is to the right and below the crankcase ventilation opening, which I was in the process of drilling out when I took this photo.

[Leewebb7]

Ok so it's supposed to be there??....that make s me feel a little better.... I'm a first time cub owner...so this is all new to me....I figured even if it wasn't supposed to be there...I don't think it would hurt anything where it was.

[Don McCombs]

Bill, just out of curiosity, why did you need to drill the ventilation tube opening out?

[Glen]

Hi,
Some of the openings cast in the block, behind the valve cover, look sort of rough, it is how they are made.
While the valve cover is off is a good time to adjust the valve clearance.
The valve clearance between the valve lifters and end of the valve stems is manually adjusted.
If nobody adjusts them, the clearance can get too small.
The valve clearance is .013", you need a flat feeler gauge to check them.
Be sure the valve lifters are fully down before checking the clearance.
All the valves cannot be closed at the same time, you have to turn the engine to make the valves close.
The hand crank is handy for that, if you have one, if you don't have one, try using the fan to turn the engine.

Below is a page from the 1955 Cub operator's manual telling how to set the valves.
https://farmallcub.com/rudi_cub/www.cle ... age-44.jpg

If you are going to remove the engine for rebuilding, and valve work, you could check the clearance after that too.

[Leewebb7]

Great info....thanks!...yeah I saw the hole it looked pretty rough.....my heart dropped for a second...lol

[Glen]

Hi,
The Cub operator's manual can help you learn about maintenance that the Cub needs.
The 1952 Cub operator's manual is at the upper left of the page, at Quick links, then go to PDF Manuals.
The experts on here recommend people read it. It has lots of info about operation, maintenance, and lubrication. There is a table of contents on page 1.
It shows how Cubs originally looked in it. The lube section begins on page 14.
I can't post the manual here.

It shows the electrical system that a 1952 Cub originally had.
Cubs made before mid 1964 originally had 6 volt, positive ground electrical systems.
They have said on here that IH didn't make a new operator's manual every year.
I sent you a PM, you get to it at the top of the page.

Below is a post that I wrote on, with info about priming the engine oil pump, like he said to do at your other post. The engine can be damaged running it with no oil pressure.
My post is part way down the page.
viewtopic.php?f=1&t=91765&start=60

[Bill V in Md]

Bill, just out of curiosity, why did you need to drill the ventilation tube opening out?

The opening had a stuck hex plug when I got the tractor. I knew it didn’t have to be removed, but I was in the process of removing other stuck, oil galley plugs, so what the heck. Now the crankcase is vented to the air cleaner. Whether it works or not, I think it should until the line becomes plugged.

[Barnyard]

Just curious as to what that hole is for.

[john2189]

Just curious as to what that hole is for.

Just a guess, would it be there to equalize pressure in the crankcase? Or the front cover?

[Gary Dotson]

My guess is that it has no purpose at all, just didn’t need material there. It’s just the way the molds are made.

[Jim Becker]

My guess is that it has no purpose at all, just didn’t need material there. It’s just the way the molds are made.

Possibly a connection between parts of the mold so the mold wouldn't collapse before the iron was poured in.