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SL-00047 Brake Caliper O-Ring Improment

I looked for instructions on how to replace the oring on the Matco brakes, but I couldn't find one. Could someone point me to the correct information? Thx
 
I have rebuilt (replaced seals) in the Matco master cylinders but not the Matco calipers.

On the Cleveland calipers used on the older RV kits, remove the caliper from the airplane and take to your workbench. Place an old rag around the caliper piston in your drain pan. Use your 'blow gun' on your air hose to "BLOW" out the piston. (blow out using the port that you removed the brake line from) Note how the piston comes out as the o-ring should be located on the side of the piston that goes into the caliper cylinder first.

Use your brass o-ring removal tool to remove the o-ring. Do not use a sharp tool that can scratch the piston as a leak may develop at the scratch.

Reassemble using the new o-ring lube to the piston with clean brake fluid. It is also helpful to lube the cylinder before inserting.

It is easier for me to do the job than it is to type up how to do it.
 
Gary,

Ok sounds simple enough.

1. Blow out the brake cylinder noting cylinder orientation.
2. Remove the o-ring with a brass o-ring pick.
3. Replace o-ring.
4. Lube cylinder, o-ring and cylinder recess.
5. Re-install cylinder w/ o-ring into cylinder recess.

Just to clarify the lube you are referring to is just brake fluid?

The timing on this is pretty good for me since I was just getting ready to install the brake assemblies onto the gear legs.
 
Yes, use the hydraulic oil that you are using for brake fluid.. but not actual brake fluid. I know a guy who used Dot 3 with not good results. Notice Vans recommends the Royco high temp fluid now too.

Instead of a brass pick, I just pinch the o-ring seal with my thumbs, then roll it out of the groove.
 
Does anyone have the part numbers for the Viton o-rings that would be used on the Matco brake calipers. Matco lists their O-ring as a MSC2-222 but this doesn’t look comparable with the number that Vans lists in the service bulletin.
 
Does anyone have the part numbers for the Viton o-rings that would be used on the Matco brake calipers. Matco lists their O-ring as a MSC2-222 but this doesn’t look comparable with the number that Vans lists in the service bulletin.

The older RV aircraft used Cleveland wheels and brakes so us old timers do not know the MATCO wheel and brake model used. Matco does have their product manuals online so one can look up replacement part numbers.
 
If that is the case then I think the Service Letter could use some work to be more clear. It appears to show the replacement O-ring part numbers (from Vans) independent of the brake MFG since it doesn't call out any manufacturers. I already ordered the stated O-rings for replacement so I hope I didn't just waste my time and money on these.
 
Service letter and Master cylinders

The Service Letter does not state one has to change the seals in the stock Van's master cylinders.

So I assume I don't need to change those if I use the new fluid called out in the Service Bulletin. Correct?
 
The Service Letter does not state one has to change the seals in the stock Van's master cylinders.

So I assume I don't need to change those if I use the new fluid called out in the Service Bulletin. Correct?

That is correct. Royco 782 is compatible with the standard 5606. They can be intermixed if you want. 782 has a higher flashpoint.
 
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