M101A2 Master Cylinder Cap Vent

[1956_4x4]

The cap on my master cylinder has a threaded hole in the center of the top. There was a deteriorated piece of plastic in the hole when I picked the trailer up from GL.

What should have been in the hole to prevent water from getting in the reservoir? I know I have changed a lot of these master cylinders when I was in the military, but I just can't remember what was used to keep water out of the brake fluid.

Smitty

 

[Recovry4x4]

Some caps and a sheetmetal cover over them. I had a few that had a small steel line shaped as a J with a piece of rubber hose to extend it. I'm working on modding a cap so I can run my brake bleeder on the trailer!

 

[coyotegray]

Im looking for a cap too..

I found this place.

Toledo Actuators | Balcrank Products Inc. Customer Service 800-747-5300 Fax 800-763-0840

Looks like they also have the military style cap..

http://www.toledoactuators.com/download/8003.pdf

I have not called them yet...

 

[KsM715]

Nice find. I looked through their website but couldnt find what I was looking for. I plan to call them monday to see if this part can be sold separately.

This would make selling a trailer much easier.

Sorry Smitty hope you dont mind me hi-jacking your thread.

 

[86m1028]

Some caps and a sheetmetal cover over them. I had a few that had a small steel line shaped as a J with a piece of rubber hose to extend it. I'm working on modding a cap so I can run my brake bleeder on the trailer!

I have had both also, & have also noticed they are different size vent holes.

 

[lindyp38]

any luck with the cap question...

can u just get match up another cap...or does it have to be vented......my other m101 doesnt have this vented type cap.....

thanks

 

[1956_4x4]

The cap in the master cylinder needs to be vented. Some have a hose and some have a small hole. The replacement master cylinder came with the cap with the small hole. I'm going to use it with a sheet metal cover over the entire unit. Because of the fluid being open to the outside air, mine will be a silicone brake fluid vehicle.

Smitty

 

[scrapdaddy]

Why can't you just drill and tap for a nipple and hose or some arangement of your own design, just to vent, no big deal.

 

[DeBang]

Here is a picture of my M101 with Surge Brake. Complete with vent. The large hose is a bit of overkill.

 

[scrapdaddy]

For some reason they did alot of them that way. No water will splash up that hose!

 

[lindyp38]

any luck with a cap...???

 

[goodguyzy]

I just picked up another m101a2 with a rusted cap, wont a deuce cap fit it? Ive got a spare Im going to try out. My first one was just rebuilt by uncle same with that same huge hose.

 

[86humv]

I have a couple M101A2 caps in nice condition available.

 

[rfischba1]

My M101A2 also had a vent cap that was rusted out and allowed water to get into the brake fluid , its now a mess with debris in there. Whats the best way to clean a take out?

 

[rosco]

A complete re-fit of the hydrolic system. Take the master cylinder off and clean it with brake clean and rinse it with alcahol. Put a kit in it. Blow the brake lines out, re -do the brake cylinders. That is probably not what you wanted to hear, but you can't clean it any other way. Its probably rusted up now anyway, and not working!

 

[goodguyzy]

same thing with one of mine, rusted top and water. It still works but ill do that cleaning one of these days.

 

[ENTRAIL]

Great find on this web site. Learned a lot. Thanks