Case 430 cyclinder head stud nuts

The oil is probably seeping down the outside of the pushrod tube(s)and pooling around the nuts.

The torque extension was Case special tool p/n CAS1257 made by Owatonna. Probably not available from Case now?

This one is Snap-on p/n S8663B. 1/2" sq drive, 11/16" box end. Still has the Flambeau paint from my last torque.

Joe

Dave , the tool you need is called a cylinder head wrench, they are still available in 11/16 & 13/16 , but other sizes are hard to find . I made the one for 7/8 for my big continental's. Oil on the top of the studs has to be coming up
the threads, Either the gasket is seeping around
the studs or the studs are not seated tight in
the block deck and oil is seeping all the way up
from the push rod cavity . In the case remove the head and remove the studs and put the sealer on lower threads on the stud and tighten them to
40 or 50 pounds then put the head back on .

Send me an email if you want a picture of a cyl head wrench,

george

one other thought , oil could be leaking from the push rod tubes . They are pushed in the head with an O ring at each end , in time the orings do get hard and shrink .

george

I have the 128 cubic inch heads in my tractors and the only way I could ever get those tight enough was find an extreme thin walled 11/16" 6 point box end wrench. If you can't find one thin enough you can buy a cheapo then take to the grinder so you have clearance. Don't use the open end side because it slips off and damages the corners of your nuts. The nuts are suppose to be torqued but I couldn't ever get the torque in the right position to work. So I torque the nuts on the other side and see how much pressure it takes to make them move and try to use the same on the nuts next to the rod tubes. Hope this works and good luck.