so I ordered a new master cylinder for my s4 t2 and it looks like the right one, except it has a port on the bottom that I will not be using. does anyone know what the size and thread pitch of this is? I went to Grainger and Lowe's and couldn't find anything to match. has anyone experienced this?

 

Flare size is 10mm x 1.0. You will need a flare plug to seal it properly, though a bolt and copper wash "can" work.

 

you are officially the man. thank you!

 

Those plugs abound on Japanese ABS units...if you're near a junkyard, just look in a later model Honda and Bob's your uncle.

 

now if i could only find one! pretty aggravated, as this was supposed to be a "direct replacement".

 

Same thing happened to me on the replacement... It's a 14x1.25. What I did was use a re-threaded standard brass plug.

 

This doesn't seem right.

 

Well... it was a long time ago and I may not be remembering correctly. I'm pretty sure it was a 14 and some thread that I could NOT find bolt/plug for ANYWHERE. I had to re-thread a standard plug.

 

Probably the hole for AAS sensor. Much larger than M10x1.0 as I got stuck with one and couldn't find anything to plug it, so got a non-AAS one.

 

Yeah it's where the red plug is in the pic. What is an aas sensor? something for adjustable suspension?

 

The fluid cup has two nipples, one goes on the port with the red plug and the other on the port with the blue plug. I think he is talking about the port in between the ports with the plastc plugs, the one with the philip screw in it.

 

the master cylinder is upside down in the pic. the reservoir is on the bottom.

 

DO NOT wrap a bolt in teflon tape and screw it in thinking that will work. Ask me how I know.

 

Yeah tex after some reading that sounds about right. so does anyone know the sizing, or have a definite solution? whatis the port actually for?

 

Was that a burn, lol? Meh...

 

Lol, I was way off. Sorry, I stand corrected

 

Looks like it's a m14 x 1.0. yeah I looked everywhere and can't find Anything wtf.

 

Do what I did if you can't source from a junkyard a sensor out of another vehicle...

Put a little rubber plug inside the hole, just so nothing can get inside the cylinder. Take a standard brass plug with a fine thread. It will look close to fitting, but won't go in. Now get a wrench, and slowly FORCE the brass plug into the threads. Back it out, blow the little brass dust out, spray some wd40 and repeat. Each time working it in a little further.

The iron cylinder is too strong and hard for the brass to do any damage. After the plug is where you need it, clean the area very thoroughly. You don't want any dust getting inside the cylinder. You can keep the rubber piece in there as long as it's secure for extra piece of mind.

It's very crude, but you won't break anything. I did it over a year ago and I've had NO ISSUES. NONE.

 

"Looks like"?
Get a thread gauge and find out for sure.

Once you are definite about size, you have all sorts of options, probably the cheapest and most easily available would be a drainplug.
I assume the original sensor sealed on a gasket not a flare, so an oil drain pan plug should work fine.

 

Thank you beefhole I'm really pulling my hair out with this thing. I've looked at all the options and this, while crude as you said, is about the only way to resolve the problem. I'm going to try to use a plug I found in the plumbing section at Lowe's early on in my search That was the right diameter. crossing my fingers!...

 

Clokker, I did use a thread gauge, my eyes aren't that good.. And it is a flare fitting from what I gathered, so not sure if a drain plug will work (?). Beefhole, did you use any kind of thread sealant?

 

^Nope.

 

I checked mine as well, M14x1.0 is correct.

 

problem solved. went and bought another one from pep boys that doesn't have the port on the bottom. gonna pull the old switcharoo haha. done and done!