1949 D4 Ram Gasket

I have not had work on that ram,but from other experience I think if you remove the cover it has a dust wiper seal in the front and the rear part of the cover pushes on chevron packing rings that do the real sealing.If there is any gape where you think the gasket would be try tightening the bolts holding it,you may be lucky and still have some life in the chevron seals.If not a good hydraulic repair shop should be able to find new one,but they are getting pricey .When putting new chevrons in just put things snug not tight at first ,run it up and down a few times and slowly tighten it until it is not leaking.As you us it and it starts leaking again just tighten a little more.The picture doesn't show it very well so it may be some other design of a seal .But the packing gland that could be tightened was very common in this time frame,and the cover looks like that type to me.
Ray

If that is a Cat cylinder there is a brass sealing washer that goes between the cylinder and the head assy. I believe the part number is the 3F9375 as shown but I can't remember for sure other than I know I have purchased them in the past.

Thanks for the suggestions. I have tightened the bolts holding the ram head to the cylinder assembly without reducing the leak. The parts diagram does not show a gasket of any sort between these major components? However, tightening the packing bolts did stop weeping from the rod seal. The leak I am trying to fix is substantial and occurs when the system is pressurized to push the blade down or up. While cutting and leveling a building pad in hard, rocky ground this fall, I was going through about a gallon of hydraulic fluid in a days use. And to add insult to the expense, the leak spurts oil toward the driver. Taking the entire ram to a hydraulic repair shop is probably a good idea that would head off my working on one problem while creating another on parts that have probably not been serviced for decades. And the rams also need new hoses.

JRMunn

If you don't want to believe me that's ok but there is a brass seating washer between the cylinder and head assy. Could be someone else didn't believe it either and left it out or buggered it up. Same seal was used on the later cylinders. You can see where there is a cross section view. Only question is the part number. Check out the 3F9375 part number and see what you get.

OM, I have never seen an old style cylinder, so is that what we are looking at? and when did they change to the new style like in the page you provided. Just looking at the page, the 3F9375 looks like it would be an o-ring under a two bolt flange that attaches to the head. Was it common for an after market blade system to use a Cat cylinder?

Here is the old style cylinder.
Cylinder change was is the early 50's, have to go by the part number stamped on the cylinder head.
Yes, some aftermarket set ups used the Cat cylinders and hydraulic system.

3F9375 is the correct number for the brass seal, I still have some in original package. The one set of cylinders I have open does not have provision for o-ring and no gasket is called out for the interface between the tube assy and the cylinder head.

You guys are sure hard to convince.

[quote="Old Magnet"]Here is the old style cylinder.
Cylinder change was is the early 50's, have to go by the part number stamped on the cylinder head.
Yes, some aftermarket set ups used the Cat cylinders and hydraulic system.

3F9375 is the correct number for the brass seal, I still have some in original package. The one set of cylinders I have open does not have provision for o-ring and no gasket is called out for the interface between the tube assy and the cylinder head.

You guys are sure hard to convince.[/quote]

I would not question what someone with so much more experience is telling me. My confusion was from not understanding how part number 3F9375 as shown on the parts diagram was related to joining the cylinder and head assemblies. With further prompting, I now see that the bracket spanning both the head assembly and gasket part numbers means that the gasket is for the whole head assembly rather than where the arrow points. Sometimes I don't see the forest from being too focused on the trees, but will get better with practice. I also appreciate seeing the parts diagram for the older style cylinder that shows what I actually have.

In order to change this gasket, I assume that the ram should be removed from the tractor and the rod must be removed from the head assembly, so it would also be a good time to change the packing and any other gaskets that need to be removed. Is there also an internal seal that I should be replacing?

Thanks to everyone for the suggestions. This has been very helpful! Tomorrow I can start trying to remove the rams, which will probably lead to spilling hydraulic fluid (that my wife has found very hard to get out of the work clothes).

JRMunn

Here is the old style cylinder.
Cylinder change was is the early 50's, have to go by the part number stamped on the cylinder head.
Yes, some aftermarket set ups used the Cat cylinders and hydraulic system.

3F9375 is the correct number for the brass seal, I still have some in original package. The one set of cylinders I have open does not have provision for o-ring and no gasket is called out for the interface between the tube assy and the cylinder head.

You guys are sure hard to convince.

[quote="Old Magnet"]Here is the old style cylinder.
Cylinder change was is the early 50's, have to go by the part number stamped on the cylinder head.
Yes, some aftermarket set ups used the Cat cylinders and hydraulic system.

3F9375 is the correct number for the brass seal, I still have some in original package. The one set of cylinders I have open does not have provision for o-ring and no gasket is called out for the interface between the tube assy and the cylinder head.

You guys are sure hard to convince.[/quote]

Well I guess I have seen the old style cylinder, because that is exact piston seal that I have. So is there an even older version? as the pic of the leaky cyl looks different than the posted break down of the early cylinder, if you look where the ell threads into the head it is shaped different, more rounded at the port instead of the usual squarish look, or maybe the tube was removed and the head tapped? Just a little hard for me to see from lighting and camera angle. That is a good tip about the teflon back-up. I see you have an Allpax cutter, I have one as well & they sure make a clean cut. I haven't checked the catalog for that size, but a wide range of hyd seals, back-up rings and wipers can be bought online direct from the manufacturer (Hercules) in Florida, just the rod wiper selection alone is huge.