Weaver WA-73, help diagnose & take apart

[amh]

Got my hands on a Weaver WA-73 jack. It is an older model, there is a “73A” stamping on the hydraulic cylinder. (I have tried to attache some pictures, sorry they are with snapped using cell phone)

When I started testing it, it was lifting the saddle (no weight) about a ½ foot then stopping with no handle resistance so I went to check the oil. The Valve plug was seemed full but the main fill plug showed a dry cylinder.

I filled the cylinder with ISO-32 oil and it lifted the saddle all the way to top position. When I tried it under weight (rear axle of my pickup) it had good resistance and moved it up about an inch (no wheel lift) then the handle lost all resistance and would not lift at all, as if plunger cup was not there.
I released the pressure, and pumped the jack up & released a few times with no weight – it worked.

After that I tried the rear axle again, this time it lifted the truck’s rear end like nothing to it. However, there was some oil leaking from both sides of the cylinder (plunger and ram sides).

So I suspect the cylinder needs a rebuild.

Did find the castleequipment web site, but wanted to get some advice from folks that may have this model (73A). Have you seen these symptoms and what did you have to replace? (cups, seals, washers etc..)

Also, is the 73A same as the 73B? (There seems to be a full kit for the 73B –> KJ-107, but not the 73A)
The kit contains:
S-6614 Piston Packing (3), S-22962 Cylinder Cap Gasket, S-4714 Piston Ram Cup, S-24648 Pump Cup, S-7412 Pump Rod Packing (3), S-17829 Large "O" Ring, S-15047 Small "O" Ring, S-2594 Ball Chamber Gasket, S-2750 Ball 1/2", S-2505 Ball 5/16", S-2499 Cotter Pin (2), S-3234 Cotter Pin.

What is a “piston packing”?

Any advice on taking the cylinder apart? What tools have you used to unscrew the large nuts? (packing nuts for plunger & ram)

Sorry so many questions, but I want to fix it without breaking anything in the process.

thanks - AMH

 

[Hiball]

Got my hands on a Weaver WA-73 jack. It is an older model, there is a “73A” stamping on the hydraulic cylinder. (I have tried to attache some pictures, sorry they are with snapped using cell phone)

When I started testing it, it was lifting the saddle (no weight) about a ½ foot then stopping with no handle resistance so I went to check the oil. The Valve plug was seemed full but the main fill plug showed a dry cylinder.

I filled the cylinder with ISO-32 oil and it lifted the saddle all the way to top position. When I tried it under weight (rear axle of my pickup) it had good resistance and moved it up about an inch (no wheel lift) then the handle lost all resistance and would not lift at all, as if plunger cup was not there.
I released the pressure, and pumped the jack up & released a few times with no weight – it worked.

After that I tried the rear axle again, this time it lifted the truck’s rear end like nothing to it. However, there was some oil leaking from both sides of the cylinder (plunger and ram sides).

So I suspect the cylinder needs a rebuild.

Did find the castleequipment web site, but wanted to get some advice from folks that may have this model (73A). Have you seen these symptoms and what did you have to replace? (cups, seals, washers etc..)

Also, is the 73A same as the 73B? (There seems to be a full kit for the 73B –> KJ-107, but not the 73A)
The kit contains:
S-6614 Piston Packing (3), S-22962 Cylinder Cap Gasket, S-4714 Piston Ram Cup, S-24648 Pump Cup, S-7412 Pump Rod Packing (3), S-17829 Large "O" Ring, S-15047 Small "O" Ring, S-2594 Ball Chamber Gasket, S-2750 Ball 1/2", S-2505 Ball 5/16", S-2499 Cotter Pin (2), S-3234 Cotter Pin.

What is a “piston packing”?

Any advice on taking the cylinder apart? What tools have you used to unscrew the large nuts? (packing nuts for plunger & ram)

Sorry so many questions, but I want to fix it without breaking anything in the process.

thanks - AMH

Very Simple Jack to Rebuild, The Tank Nut uses a adjustable spanner to remove, You can use a Pipe Wrench on the Pump Piston Nut. In front of the PUmp Piston Nut there is 3 pieces of packing and its designed to be tightened over the years. You shouldnt remove the valve plug, Its not a fill hole. The Fill Hole is on the Resevoir and ive known those jacks to Plug up on the Resevoir line from the Pump to the Resevoir. I would recommend taking the unit outside the frame and then inspecting the Soft parts. The Frame is a Welded together and it only takes pulling a couple cotter keys, The Ram/ladder Cotter key and disconecting the Release and pumps Linkage. The Kit price should be around $50 bucks, If its more than that let me know as i have a local supplier here.

 

[amh]

Hiball, thanks.
1. Are the 73A and 73B kits the same? (kit KJ-107)
2. What are the soft parts? Do you mean take it apart & look at cups, seals, packing & o-rings?
3. When I take cylinder apart for inspection, will it be obvious what is causing the leaks (ram & piston side)? Are there common culprits?

rgds,
amh

 

[Hiball]

Hiball, thanks.
1. Are the 73A and 73B kits the same? (kit KJ-107)
2. What are the soft parts? Do you mean take it apart & look at cups, seals, packing & o-rings?
3. When I take cylinder apart for inspection, will it be obvious what is causing the leaks (ram & piston side)? Are there common culprits?

rgds,
amh

1. I believe so, I know there was a difference in Pump piston sizes on the 72's but think the 73's are the same.

2. Yes, Soft parts are the Pump Piston and Main Ram Cup.

3. You should be able to see if there are any splits etc by looking at the parts. The only Orings used on those jacks is in the Release.

4. It sounds like a Lack of Oil issue or possible Valve issue. As i said, I would take it apart, flush the system and make sure you get the gunk out.

 

[Harry Gerrard]

I ordered the rebuild kit on the Castle Equipment Co website, and I too have a Waver 73A. The website lists 73B.
The cylinder on the 73A must be slightly smaller, as the ram cup seal I installed did not want to go in. I ended up pushing, pushing, pounding,, got it all back together and it did not want to operate.
I ended up having a local guy come and install the seal kit and he had a leather ram seal he used.

 

[Hiball]

I ordered the rebuild kit on the Castle Equipment Co website, and I too have a Waver 73A. The website lists 73B.
The cylinder on the 73A must be slightly smaller, as the ram cup seal I installed did not want to go in. I ended up pushing, pushing, pounding,, got it all back together and it did not want to operate.
I ended up having a local guy come and install the seal kit and he had a leather ram seal he used.

Did you contact castle? Was the original seal a leather or poly? You have to be real careful when installing the new seal, because it has clear the threads/fill hole. If it was a leather it should have been crimped prior to installation, so it would clear the above items.

Anytime it becomes necessary to "pound" a new seal into a cylinder.. Something is wrong.