1969 Elan S4 Tandem Master Brake Cylinder Question

[lotocone]

You're welcome Glen. It's great reading your posts. I'm always learning something for next year when I'll get back to working on my car.

Bob

[Certified Lotus]

There is always a surprise when it comes to Elans...... either that or I just don't know these cars well enough.
So I get my new old stock master brake cylinder cap with cork float (probably the last one on the planet) from a great source in the US and I go about installing it today on the metal extension above the plastic reservoir for the brake fluid. I fill the reservoir enough for the cork float to make contact with the electrical connection in the cap and all of a sudden I see brake fluid seeping out of the lower part of the metal canister. What the heck?

Disassemble and look closely to find out compared to the photos on this post I have replica metal canister that does not seal to the plastic reservoir. It doesn't screw down far enough to seal.

So now I am looking for the metal canister. Does anyone have one for sale?

Reproduction that leaks

OEM metal tank that I want!

[pharriso]

Glen, there should be a plastic cap to the master cylinder reservoir, it is drilled & a brass fitting clamps the cap to the metal sovy can with a seal between the two. All of the parts are shown here:

Please pardon the image quality

It's not a particularly robust design, if either the seal in the plastic cap, or the seal between that cap & the bottom of the reservoir are not perfect the assembly will leak.

I am unclear from your picture if these is a plastic cap on your reservoir? Or if the metal can screws directly onto the reservoir?

[terryp]

Phil
That's my bench!!!

Terry

[pharriso]

Phil
That's my bench!!!

Terry

Actually, both pictures of the SOVY can are of the same unit!! Pre-restoration & post-restoration & installed.

[Certified Lotus]

Gotta love this site for getting answers! Thanks for the additional info Phil.

Here is my master cylinder from the side view:

Master Brake Cylinder side view

The metal canister (in my case its aluminum) screws onto the top of the master cylinder reservoir with a rubber gasket in between. And the red cap with the cork float screws on the other end of the metal canister.

Master Brake canister and SOVY lid

The rubber gasket that came with the metal canister is too thin as it won't seal the unit to the plastic reservoir. The canister is not an OEM version. Looks like someone custom made this.

The simple solution is to find a thicker rubber gasket. I need a 1-3/4" OD gasket that is 1/4" wide (thick). And it needs to hold up to brake fluid.

The more difficult solution and expensive to find an OEM canister. But after looking at Phil's photo it looks like it pressure fits on top of the cap (?).

I think I need to find a rubber gasket or O-Ring the right size. Any suggestions?

[pharriso]

Yes, but what screws onto that? A plastic cap/ brass adapter/ sovy can, or does the can screw on directly?

Show me the bottom of the can please

[Certified Lotus]

Phil, here is the bottom of the metal canister (its threaded for receiving the male thread of the master cylinder reservoir).

Bottom of metal canister

with gasket in it

The gasket is way too thin. I need a 1/4" wide rubber gasket or o-ring to seal.

[pharriso]

Looks like someone has been busy on a lathe.... totally custom solution... I wanted to see if you had the same sealing solution as the original, but obviously not.

Could you use 2 or 3 of those seals? Looks to be a standard reservoir cap seal, Ray probably has them & I'm sure you have him on fast dial by now...

[Certified Lotus]

That's what I thought Phil, custom made on a lathe. Great idea just not perfectly executed.

Multiple gaskets laid up together are a potential for leaks. Not a good idea, especially with brake fluid. I will have to hunt down the right size that can handle being emersed in brake fluid.

I could also put in on a lathe and fix the problem. Drew suggested that (he has a lathe) but I thought finding a gasket the right size might be easier.

[gjz30075]

Glen, here's the bottom of a SOVY can (powder coated black, btw). A cap just like what's on an oem
reservoir but with a hole in the middle and attached to the can. Nothing, as far as know, attaches to
the threaded fitting that you see inside the oem cap. Someone could have changed the fittings in
the past, but this was on my car since '78.

[Certified Lotus]

Greg, that is the detail I was looking for. Thanks. Now I see my canister isn't even close to what the OEM was. The big question is does anyone have these anymore?

By the way, it's a very strange design........

[oldchieft]

With all the gnashing of teeth and tearing of hair these things cause, I am starting to look more kindly on my Delta P valve.

Jon the Chief

[Certified Lotus]

Had to laugh at your comment Jon. Well, now I have two red top SAVOY float sensor caps. One with a "modified cork" but no metal canister to fit them in.

Anyone want to trade a canister for a red cap (the one that the cork is a bit modified) ?

SAVOY Caps

[pharriso]

Anyone want to trade a canister for a red cap (the one that the cork is a bit modified) ?

DSC06909.jpg

Glen, I was waiting to dig through my parts before posting but I believe that I kept my old SOVY can & brass fitting after replacing mine with the one that I renovated (from TerryP).

Let me dig it out tonight & post pictures....

You will soon have all my spare parts.... Service manual. Jack... SOVY can...