Davis 185 / Backhoe Swing Cylinder

[granitepeak]

Hello everyone,

While all of the cylinders will relax within minutes and therefore need to be rebuilt soon, I have one that has external leaks that I want to deal with now.

Going through the various manuals and parts books for the loader and backhoe, I have been able to determine the sizes of the o-rings and backup washers. Luckily for me, they are the same sizes as those used for the loader which I worked on and have extras. If possible, I would like to have all the parts on hand before opening it up. This is going to be more of a quick repair than a rebuild, which I will look at doing once winter kicks in. These 1950's cylinders were from the industrial division of Cessna Aircraft.

1. If the backup washers are originally leather can they be replaced with non- leather parts?
2. I can not find info on the seal and am wondering if shaft size and bore is all that is required to determine the replacement part or do they range in thickness and depth that require it to be taken apart first?

Thank you,
Don

 

[granitepeak]

Its a mess

 

[wdchyd]

Yes, it’s a mess. What’s the hole in the side of the gland head? Maybe a set screw area to prevent suck back? You may have to braze that scratch to clean it back up. I’m assuming it has a retainer ring to hold the gland.

Looks like they may have welded up the leading edges of the gland to tighten up the clearances between the gland head and cyl barrel.

Are they using only oring and two backups for piston seal, or is it a piston “T” seal?

 

[granitepeak]

I do not know. They made a slip on cover for the end of the cylinder the setscrew goes through the cover into the gland head. Can't get the other end off, I knocked out the pin and tried my 20 ton press. Need that off to rebuild it backwards.

 

[granitepeak]

If it wasn't so quick... I suppose I could live with just one swing cylinder? Its leaking to but from the outside does not seem so beat up.

 

[wdchyd]

The piston head should be threaded on, the roll pin would not be strong enough alone to hold.

 

[granitepeak]

I called the machinist / welder I have used to make some parts in the past. He is coming out to look at it. In the mean time, I was able to get it running with one swing cylinder and I have no issue controlling it.