Lift ram arm cracked lift cover.

[Dave G9N]

The lift ram arm in my daughter's 2N appears to have been driven up so far that it damaged the rear housing and lift cover. We are replacing the lift cylinder because it has been leaking down. While scraping the gasket residue from the rear housing, I found cracks and a raised hump where the lift ram arm 9N-545 apparently was driven into the center housing. After finding this, I examined the cover and found corresponding damage. With the cover off and the cylinder removed, the hydraulic ram arm can contact the cover in this area. Surely the lift travel is controlled in a way that would not cause the arm to bottom out. I can't think of anything that we have done in the short time we have had the tractor could have caused this.

The damage seems to have been similar in both the cover and housing, so the gasket does not appear to have been leaking. If I try to straighten the area, I am sure that it will break. That is to say fall apart, it is clearly broken, just not completely broken off. The only repair that I can think of would be to braze the cracks. That would involve collecting and reassembling the pieces.

Has anyone seen similar damage?
How can this happen?
Does anyone see a good reason not to use it as is?

This is the area where the damage was found:

The gap between the top cover and the ruler shows the depth of the damage in the top cover.

 

[shaun wallace]

Have seen several times. Doesnt hurt anything. Caused by lift arms raised too high by either mechanical means or lift not adjusted correctly.

 

[JMOR]

(quoted from post at 23:24:42 11/29/23) Have seen several times. Doesnt hurt anything. Caused by lift arms raised too high by either mechanical means or lift not adjusted correctly.

...and another possibility is that control valve got stuck in lift position and the mechanism designed to stop lift (see "ears" at rear of piston on control arms) could not do its job/intended function.

 

[Dave G9N]

Thanks, Shaun, that's good to know.

Jesse,
When you say in the diagram "at full lift the piston contacts these 2 points..." is it the piston or the end of the cylinder that makes contact? I am asking because the Turkish cylinder casting that I installed on my tractor has a shorter nose, so it would not contact the two points. If it is the piston, it will be half way out of the cylinder that I installed by then. Probably not an issue because it shouldn't go that far normally.

The new casting my daughter bought has a nose somewhere between the length of the one I bought and the original. The front end looks like some grinding of the opening in the center section will be needed to make it fit. At least that part is easier than it looks.

A side note that I will bury here here rather than starting a useless 'woe is me' thread:
After rebuilding the pump on my 2N, replacing the cylinder and posting a long winded description of the need to grind the center housing, the pump base cracked next to the test port. It was a bit of a disappointment to have the lift operate nicely for an hour or so before it failed in a different way. I noticed some oil under the tractor after using it just enough to show that it was working. It seemed to be coming from the plug, so I checked to see if it was tight. It turned easily, so I snugged it up and tried the lift to see if the leak stopped. It was leaking faster. It was not very tight, so I turned the wrench a little more, causing it to leak faster. then the crack opened up on the top, next to the plug. Found a good (I hope) used one in Ohio and will try again. The used one has the original side plates. The ones that fit without grinding.

 

[JMOR]

(quoted from post at 22:21:37 12/01/23) Thanks, Shaun, that's good to know.

Jesse,
When you say in the diagram "at full lift the piston contacts these 2 points..." is it the piston or the end of the cylinder that makes contact? I am asking because the Turkish cylinder casting that I installed on my tractor has a shorter nose, so it would not contact the two points. If it is the piston, it will be half way out of the cylinder that I installed by then. Probably not an issue because it shouldn't go that far normally.

The new casting my daughter bought has a nose somewhere between the length of the one I bought and the original. The front end looks like some grinding of the opening in the center section will be needed to make it fit. At least that part is easier than it looks.

A side note that I will bury here here rather than starting a useless 'woe is me' thread:
After rebuilding the pump on my 2N, replacing the cylinder and posting a long winded description of the need to grind the center housing, the pump base cracked next to the test port. It was a bit of a disappointment to have the lift operate nicely for an hour or so before it failed in a different way. I noticed some oil under the tractor after using it just enough to show that it was working. It seemed to be coming from the plug, so I checked to see if it was tight. It turned easily, so I snugged it up and tried the lift to see if the leak stopped. It was leaking faster. It was not very tight, so I turned the wrench a little more, causing it to leak faster. then the crack opened up on the top, next to the plug. Found a good (I hope) used one in Ohio and will try again. The used one has the original side plates. The ones that fit without grinding.

t is the piston moving out beyond end of cylinder that contacts the linkage and stops further lift by closing pump inlet valve.

 

[Hobo,NC]

I would replace it my reputation is not worth the gamble. Its your tractor your call. I have a few of those covers I don't remember ever selling one and would not unless its a walk up customer.

Its a interesting issue.

 

[Dave G9N]

(quoted from post at 05:42:19 12/02/23)

(quoted from post at 22:21:37 12/01/23)

Jesse,
When you say in the diagram "at full lift the piston contacts these 2 points..." is it the piston or the end of the cylinder that makes contact?

t is the piston moving out beyond end of cylinder that contacts the linkage and stops further lift by closing pump inlet valve.

was afraid of that. I didn't really think you were likely to have worded that imprecisely in your picture, but it is good to be sure. So when the piston comes a short distance out of the original cylinder, it's by design and not a problem. Another 3/4" worries me. We should have seen some complaints by now if it was an issue.

I wonder if the aftermarket guys thought it through. The piston will come about 3/4" farther out of the new cylinder. I didn't measure the difference, but I did line up the mounting holes and take a picture. It's inside the tractor now. The one we have opened up now is only about 1/4" shorter. The two in the picture are an original piston and the one I put in my tractor last summer. The closed end is about the same on both aftermarket cylinders and will hit the edge of the opening in the top of the center section. Grinding is easy enough. Cleaning all of the grit out of there is the hard part.

 

[TheOldHokie]

(quoted from post at 16:33:57 12/02/23)

(quoted from post at 05:42:19 12/02/23)

(quoted from post at 22:21:37 12/01/23)

Jesse,
When you say in the diagram "at full lift the piston contacts these 2 points..." is it the piston or the end of the cylinder that makes contact?

t is the piston moving out beyond end of cylinder that contacts the linkage and stops further lift by closing pump inlet valve.

was afraid of that. I didn't really think you were likely to have worded that imprecisely in your picture, but it is good to be sure. So when the piston comes a short distance out of the original cylinder, it's by design and not a problem. Another 3/4" worries me. We should have seen some complaints by now if it was an issue.

I wonder if the aftermarket guys thought it through. The piston will come about 3/4" farther out of the new cylinder. I didn't measure the difference, but I did line up the mounting holes and take a picture. It's inside the tractor now. The one we have opened up now is only about 1/4" shorter. The two in the picture are an original piston and the one I put in my tractor last summer. The closed end is about the same on both aftermarket cylinders and will hit the edge of the opening in the top of the center section. Grinding is easy enough. Cleaning all of the grit out of there is the hard part.

The piston should be hitting the linkage regardless. IIRC that shutoff point is adjusted at the quadrant mounting flange. Fill the divot and sand flat. Worst it will do is leak a bit.

TOH

 

[Dave G9N]

(quoted from post at 15:47:49 12/02/23)

The piston should be hitting the linkage regardless. IIRC that shutoff point is adjusted at the quadrant mounting flange. Fill the divot and sand flat. Worst it will do is leak a bit.

TOH

f it leaks, it will leak water in, not oil out. I think this will have to depend on some gasket sealant back there. At least it is not going to see standing water.

The divot is across the entire faying surface of the rear of the opening in the center section. It is about 2 1/2" wide and 3/16" deep as you can see in the picture. The ruler is flat on the undamaged areas on either side. The gap under the ruler is the depth of the dent. Both surfaces are cracked through and wedged together by the surrounding material.

The damage is too deep to grind. The cracked material will just fall out if I try to flatten it. It looks like the only way that this will seal is for both deformed surfaces to be sealed with gasket adhesive and hope for the best. At least the distortion is pretty well matched on both sides and the joint was still pretty tight in spite of the distortion. The only real strength in that area will be the paper gasket. If it fails, my 9N gets the Sherman trans and we part out the rest.