Air blowing up through oil filler.

[havoc1482]

So this is something that has always been on my mind, there is air that blows up though the oil filler cap. Its quick puffs relative to the engine RPMs. I ran a compression test about 2 months ago and I had 90 across the board. Its been blowing air longer than that. I always thought it was the movement of the rockers just churning air.

I've heard this is caused by a bad ring, but I can't imagine it could be that because of the 90psi on each cylinder, unless each ring somehow has the exact same wear lol.

Also, off topic, but does anybody know where I can get a gasket set for my hydraulic pump? I'm getting fed up with hyd. fluid going into my crankcase

[Matt Kirsch]

90PSI is not great, and there is no doubt some air is escaping past the rings and getting into the crankcase. It's nothing to worry about IMHO. I believe this is what they call "blowby" and given the equal status of all four cyinders, I would say they're all equally guilty, rather than it just being one bad cylinder.

AFAIK there is no "set" of gaskets. You actually need a seal, not a gasket. Unfortunately there is no set or kit. You have to get the parts separately from your CaseIH dealer. If you call Ken Updike at Johnson Tractor he knows exactly what you need off the top of his head. That's as good as any kit. You need to know which of the two possible pumps you have also. One is actually an O-ring not a seal IIRC.

[havoc1482]

90psi is great considering from the factory rating compression for a C113 gasoline engine is 102PSI at cranking speed. 65+ years and only 10psi across the board.

Now, if you based your assumption off the C60 which is 125PSI, then yes, 90 isn't great.

But I guess that lost 10-12 psi is whats causing the air blowing up. All I needed was a little reassurance.

Also, thanks for the info about the pump seal. I used gasket colloquially with seal.

[Don McCombs]

Here is a list of part numbers and substitutes for Super A/Super C hydraulic pumps. McMaster-Carr has the O-rings. Be sure to get Buna-N.

351818R1 gear washer – substitute 3/8” inside toothed washer
350706R3 manifold gasket
350708R2 pump gasket
350667R1 manifold o-ring - #115, 11/16 X 7/8 X 3/32 Buna-N, 2 required
353836R1 shaft o-ring - #208, 5/8 X 7/8 X 1/8 Buna-N, 1 required
G46055 body o-ring (square cross-section) - #228, 2-1/4 X 2-1/2 X 1/8 Buna-N, 1 required
350651R1 strainer gasket

1/8 X ½ woodruff key
3/8-24 jam nut

[bbushnell]

Hey Guys, I am new to all this would appreciate a bit more clarity on this issue of Hydraulic Fluid leaking into crank case. I have that problem on my 1972 IH Cub. If I am right, the pump is up front, left side of engine (drivers perspective). It is clear I need gaskets or seals, but can someone walk me through this? Is it as easy as removing the pump and replacing seals? And of the part numbers listed in the earlier post, not sure which I would need? How do I figure out what type pump I have? Thanks for being patient with my lack of knowledge on this. Bob

[Don McCombs]

The part numbers in the previous post are for a Super A, not a Cub. Here are the corresponding numbers for the Cub. You will notice that there is some overlap.

351818R1 gear washer – substitute 3/8” inside toothed washer
352034R2 manifold gasket
351677R1 pump gasket
350667R1 manifold o-ring - #115, 11/16 X 7/8 X 3/32 Buna-N, 2 required
252739R1 shaft o-ring - #112, 1/2 X 11/16 X 3/32 Buna-N, 1 required
353828R1 body o-ring (square cross-section) - #134, 1-7/8 X 2-1/16 X 3/32 Buna-N, 1 required

1/8 X ½ woodruff key
3/8-24 jam nut

Replacing the seals is as simple as removing the pump, but you will need to drain the system first and then remove the manifold tubes. Just keep everything squeaky clean. I think there are several "How To's" that can guide you through the process.

[bbushnell]

Thanks Don, Much appreciated.

[havoc1482]

Hey Don, just as a followup I can't find "#351818R1 gear washer" in the CaseIH partstore database. Also, I'm unfamiliar how to navigate through McMaster-Carrs website.

[Don McCombs]

I guess the washer has a new number, 352037R1. But, unless you enjoy paying over $40 for a washer, I suggest the substitute. Or re-use the old one.

Go to the McMaster-Carr web site, http://www.mcmaster.com . Enter "112 o-ring" in the upper left search box and hit ENTER.

[havoc1482]

Its just a regular 3/8 inner toothed washer?? Wow, what a scam from CaseIH lol

[Don McCombs]

Yes. Be sure to torque it to the value required by the size nut.

[havoc1482]

Okay so I took the pump apart. Gaskets and the square cross section o-ring were torn up. Now I have one question, I have no idea where one of the o-rings goes. #208, 5/8 x 7/8 x 1/8. I can't find where this would have gone (because I can't find the old one).







I'm taking a guess, but maybe it goes here? It fits the diameter of the housing, but I don't know.

[Don McCombs]

I've not had mine apart, but if it's made like the Cub pump, inside the bore (at your second finger in the last photo), there should be a groove. It goes in there.

[havoc1482]

Its hard to see, but like this?:



It fits in there snuggly and I can put the two halves together without problems when its in there. In that position one side of the oring is going to be against the spinning pump shaft, does that make sense? FYI there was no oring at all in there when I took it apart, could be that it was missing.

[Don McCombs]

Yes, but it looks like you have the remnants of something metallic on the shaft. What is that?

The attached parts diagram may help also.