Cylinder seals

[granitepeak]

Hello everyone,

On my Davis 185 backhoe the boom and dipper use the same cylinder. So far I have pulled the dipper and the bucket cylinders. Pulling the number off the seal. I found the seal for the bucket(Assuming the right seal was used). Even though the dipper and bucket use 1.75" shafts, the dipper number of the seal is different. When searching for that part, 63X899 I do not find a matching replacement. I am thinking the best way to get the right seals is to measure the bearing for outside and depth dimensions. Is there a suggested seal type to use so I can find it by size rather than part number?

Thank you!
Don

 

[flyerdan]

I've got a big book of seal cross reference (one for bearings and v-belts as well), and with your part number of 63X899 that suggested an ISI group 61903, which has a couple colums of different manufacturers part numbers. Hopefully you'll be able to find something.

 

[wdchyd]

There is more than one seal in that cyl, are you measuring only the wiper?

I’m assuming you meant 1.750” .......or 1.772” (metric 45)

 

[granitepeak]

I've got a big book of seal cross reference (one for bearings and v-belts as well), and with your part number of 63X899 that suggested an ISI group 61903, which has a couple colums of different manufacturers part numbers. Hopefully you'll be able to find something.

View attachment 643482

Thank you, with your help I was able to figure it out. The bucket seal was not the correct spec'd part.

 

[granitepeak]

Yes, the wiper seal. the 1.76" was a typo should have been 1.750"(I corrected it after you pointed it out)
I know there are o-rings, backups and the cups. Am I missing something else? When I took it apart most it was eaten.

This thing is a headache. The images in the parts book do not match up with cylinder and so I have to confirm each part sizing.


Next issue is that the parts book shows a 2 part piston with cups. Actual part is a single unit with 2 groves. Nothing that I see in cups makes sense to this novice.



Thanks,
Don

 

[wdchyd]

Yes Don, only thing I see is the expander ring from a poly loaded-lip seal. You may want to check out the inside bore because of the condition of the piston head, the bore may be a little too rough and wearing out your seal prematurely or something else going on like a compatibility with the seal material and a foreign substance in the hyd oil.
Those seals that belong in those grooves are very common, your local hyd shop will have those on the shelf.
What are the dimensions of the grooves and bore size?

 

[wdchyd]

Where are you located?

 

[granitepeak]

Bill,

The machine was built in 1956 and if the story was correct when I bought the Massey 202 with the Davis loader / backhoe, it sat in a field for 20 years. The original pump had no filter of any kind. Could I hone the bore or does it need to go to a shop? The bore is 3.5", groove is .25" deep and .375" wide. I need to call around and find a shop that has a parts counter. I am in a smaller town in central California.

Thanks,
Don

 

[wdchyd]

That piston head is newer than 1956, someone updated it to fit. Likely they may have changed the style of rod seals from the OEM design too.

 

[granitepeak]

Makes sense as the piston in the book is two parts.

 

[wdchyd]

That would explain you asking about the leather piston cups.

Here’s what belongs in those two grooves, either of these two styles.

 

[granitepeak]

The bucket cylinder does have leather cups. Going to send you a message.

 

[granitepeak]

That would explain you asking about the leather piston cups.

Here’s what belongs in those two grooves, either of these two styles.

View attachment 643581

What would be the name of the type of seal in the picture? After calling a number of shops, I finally found one that has parts but he asked what kind is needed for the piston?

Thanks,
Don

 

[wdchyd]

U25-3.00-37B...(black seal) ...or........DPU25-3.00-37 (yellow seal)

Parker #25003000-375B


They’ll know