Deuce Master Cylinder, different styles?

[Tlauden]

So Ive searched and havent found any other master cylinders like this. I got this replacement MC today from saturn, got it home and opened it up and was disapointed to see a different style. Ive searched a ton of A2 and A3 threads and what I found in the A2 was styles like my old MC, and the A3's seem to use some sort of dual chamber MC for a split brake system. My current MC is working but pitted pretty bad so I wanted the peace of mind of a working MC. I have all the parts to put a remote resivior but need that 1/8" pipe thread cap. It looks like the same exact part except for that cap. In the pic of the new cap you can see the small vent hole.

I guess my question is could I JBweld the cap vents shut and drill and tap a 1/8 inch hole on the top of the new MC's resivior? I called saturn and they said its the only style MC they have. Whats your thoughts?

Attached are pics. Green one is old, gray one is the new MC.

Sorry for thw sideways pics, it refuses to upload them correctly

 

[sandcobra164]

My old one looked like your new one, small cap and it was already drilled for the vent line. My new one has the large cap and is drilled for a vent line but has a breather up top. I couldn't get the old vent line fitting out of my old M/C cap but I'll get a fitting for it soon. Here's another cap tossed in the ring. My buddy has a new M/C for an M211 and it looks exactly like my old one. The M211 had a completely different brake system. For starters it had two wheel cylinders per wheel and a much more remote air pack. The M/C's look identical. I think what you have to put on it is good to go, just work on finding a small cap with a vent line hook up. I wouldn't drill and tap the M/C you're wanting to put on as the fine shavings created by drilling my wind up somewhere they don't need to be.

 

[Tlauden]

Thanks, I just never realized there was more than 1 style, guess I should figure a 40 year old design has more then 1 manufacturer lol

 

[Big Z]

My old one is also like your new one. Only thing different is the cap was already threaded 1/8". I imagine you can just drill/tap the cap. And if I find my old one I could send it to you too.

 

[welldigger]

Just drill and tap the cap and call it a day.

 

[jasonjc]

It seems to me that one of my trucks has a MC with a diffrent size cap also.

 

[drivebymashing]

I have the same problem my cap is plastic. I cant drill and tap it.

 

[SCSG-G4]

There was another thread within the past 10 days with a link to replacement caps for the MC. (IE the same cap fits 1937-1959 GM single circuit MC's). Life is good - same MC on CCKW as the deuce. Buy a new cap for $8.50 and drill and tap it. Clean up the shavings, then install it.