[GThound]

My old master cylinder cap was a nasty, rusted corroded mess.

So, I figured I would replace it. I tried to order a shiny new one from Opel GT source. It was $40 some odd dollars, but it was out of stock, and still out of stock.

The thought was to have an inner plastic cap and an outer aluminum shell. Since I do not have a lathe, I went with an octagonal shape for easy finishing of flat surfaces.

I tried designing and 3D printer a cap out of ABS. It worked well at first, but it fell apart with exposure to the brake fluid overtime.

 

[Lindsay]

Plastic Master Cylinder Cap.
Part: 4045A - Price: $7.00

https://opelgtsource.com/search/2606/details

 

[Lindsay]

Master Cylinder Cap

First let me say I consider this a temporary solution since brakes are important and a sealed master cylinder is important to keep moisture out but when in pinch.....the threads in my master cylinder cap fell apart, I grabbed the closest thing, a bottle of WeedBGone, big ugly yellow safety type...

www.opelgt.com

 

[GThound]

So, here is the mold for the aluminum piece. It looks just like the final product, but is made of plastic.

 

[GThound]

So, here is the final product in place, with the opel GT source $7 cap inside!

 

[The Scifi Guy]

Pretty cool, nice job!

 

[G.v.Mainberg]

Casting aluminum - I'm impressed!

Dieter

 

[Commodåren]

You were not tempted to put MG on the cap ?

 

[opelmeister]

Master Cylinder Cap

First let me say I consider this a temporary solution since brakes are important and a sealed master cylinder is important to keep moisture out but when in pinch.....the threads in my master cylinder cap fell apart, I grabbed the closest thing, a bottle of WeedBGone, big ugly yellow safety type...

www.opelgt.com

I may be able to help and because of a creative solution like this, I check out my stuff and here is what I have. I'll also add some pics to my current Parts for Sale.