T3 linked brakes splitter issue

[Dave Bonsall]

I’m overhauling the linked brakes on my 77 T3 and I’m questioning the way the various brake lines connect to the splitter. As taken apart, and been that way for 30 years, the connections were in the following order:-
Top: front caliper
Middle: brake light switch
Lower: master cylinder
Bottom (in line with body of splitter): rear caliper.
My thought is that the front caliper and master cylinder are the wrong way round? The top port has a very restricted opening (3mm?) which matches the outlet in the m/c. See photo.
Any thoughts please?

 

[Nordicnorm]

The top small hole will give more power to the front brake than the rear., which I think comes out of the bottom (the 4th hole in your picture). Hydraulics are fascinating.

 

[V700Steve]

Looked at my LM3, top is front(hard line), center is switch, bottom is master, under bottom(strait down) is rear brake
You want a new one? I would consider one from a CalVin, same thing w/a bleeder on top. Made for newer calipers so may act different or not.

 

[Dave Bonsall]

Thank guys that’s really useful. Hydraulics fascinating but baffling!
A bleed nipple would be handy but I’m hoping my simple pressurised bleeding kit will do the job. A project for the holidays!

 

[Unimog63]

My 1975 850 T3 project is missing some parts of the braking system. This analysis of the distribution block is very helpful, mine is mounted left rear of frame. Bottom port is plugged, only the rear brake is connected to the foot master cylinder. I think the previous owner's plan was both front calipers would use a double banjo connection to the front master, no method of actuating the brake light. I need a more comprehensive parts list, there must be a distribution block for the front master that incorporates a pressure switch for the brake light. Location to mount it? I can purchase the hard brake line for the front caliper to rear block, how do I mount it? Where is it routed? How is the left front caliper flexible hose connected to the hard brake line? Needless to say I need a better guide than the Haynes book I have. . .

 

[Amboman]

My 1975 850 T3 project is missing some parts of the braking system. This analysis of the distribution block is very helpful, mine is mounted left rear of frame. Bottom port is plugged, only the rear brake is connected to the foot master cylinder. I think the previous owner's plan was both front calipers would use a double banjo connection to the front master, no method of actuating the brake light. I need a more comprehensive parts list, there must be a distribution block for the front master that incorporates a pressure switch for the brake light. Location to mount it? I can purchase the hard brake line for the front caliper to rear block, how do I mount it? Where is it routed? How is the left front caliper flexible hose connected to the hard brake line? Needless to say I need a better guide than the Haynes book I have. . .

So many questions...

Yes, there was a "distribution block" in the front brake circuit originally. #7 in this illustration.


The block bolts to the front of the lower triple tree.

The hard line from the rear block to the left front caliper isn't really "mounted" anywhere other than a wire retainer with rubber grommet holding it near the front. #50 & #51 in this illustration. The hard line runs along the left frame rail. #47 is a small split rubber piece to keep the line from rubbing on the frame.




By the way, the above illustrations are for a Convert, but it's the same other than the front master cylinder shape, and the mechanical parking brake on the rear.

I do have a T3 frame with the hard line still attached and can shoot some photos if necessary.

 

[john zibell]

You really want to keep the brake light switch. It may be possible to add a second brake line for the front by using a double banjo bolt where the line from the master cylinder attaches to the block.

 

[Amboman]

Brake line photos. At the rear "distribution block".

Runs along the frame. Rubber protector where it goes up over the frame.

Forward end where the flexible line attaches.

This is the holder - the end of the flexible line fits into the grommet.


Front brake 'block.

 

[Unimog63]

Ahh, said the blind man! That's VERY helpful. I was piecing together a parts order to recreate this and the location of components was still baffling me. My rear block has a plug in one port but the beginning of this thread explains the port usage.
I'm off and running, at least until I stumble again. Many thanks