late BN1 brake spring anchor pins

[whitworth]

While replacing wheel cylinders & brake lines I've noticed all four (both sides) front return springs are different. A testimony to the 'amateur' shops who worked on this car for the past 20 years. Anyway, the BN2 Supplement (plate AH 184.A.)shows what looks like small grooved pins to anchor one end of the spring. I believe later BN1 cars as well as the BN2 used these pins, which are missing. The 184 page aftermarket AH parts catalog I have lists different springs but mentions no pins. Anyone know where I can purchase these pins? I have a lathe, even some dimensions would help.

 

[zblu]

Not referring to the steady pins are you?

 

[whitworth]

Re: late BN1 brake spring anchor posts

No, these are approx. 5/16" in dia with a groove for the loop of the return spring to anchor on/in and mount thru the backing plate.

 

[zblu]

Re: late BN1 brake spring anchor posts

From memory the springs hook thru holes on the brake shoes each side, and are best set up and then installed with some grunt into the slots on the slaves, cant recall the posts you refer to, sure they are original?

 

[mjobrien]

Re: late BN1 brake spring anchor posts

The only posts on the back brake plate is the Steady post - it has a soft bushing for grease that slips over it prior to putting the shoes back on. If this is missing a simple bolt, nut of the right size seems like it would work.

Both springs attach to the shoes via holes in the center plates of the shoes.

hope this helps,
Michael.

 

[Dave Russell]

Re: late BN1 brake spring anchor posts

The only posts on the back brake plate is the Steady post - it has a soft bushing for grease that slips over it prior to putting the shoes back on. If this is missing a simple bolt, nut of the right size seems like it would work.

Both springs attach to the shoes via holes in the center plates of the shoes.

hope this helps,
Michael.

True, the rear brakes are as Michael says. See the attached pic.

The front brakes however, have anchor pins for the inboard ends of the springs. On my car these pins are firmly riveted to the backing plate. I can't imagine how yours got detached. See attached pic.

It wouldn't be hard to fabricate new pins. Length & upper groove position to make the springs level & a shouldered bottom suitable for riveting into the backing plate. I would expect that this end could even be inserted into the plate & braised rather than riveted.
Good luck,
D

 

[whitworth]

Re: late BN1 brake spring anchor posts

Thanks Dave, these missing anchor pins are typical of what happens when too many amateurs work on a 53 year old car.

 

[zblu]

Re: late BN1 brake spring anchor posts

Dave, just to satisfy my curiosity, I thought the BN2 was 5 stud whilst somewhere in the BN1 production line was where it changed from 4 to 5 stud, yet acording to the illustrations the 4 stud continued into the BN2, am I right in surmising this?

 

[Dave Russell]

Re: late BN1 brake spring anchor posts

The illustrations I attached show only the brake backing plate securing studs. Four front & four rear on all models.

On the actual hub to hub extensions, which secure the brake drums, the BN1 had four studs on the rear. Later BN1 & BN2's had much stronger five stub mounting.

Both BN1 & BN2 had four stud mounting of the front drums.
----------------------------
A little known problem with the early front brake wheel cylinders.
The flex line connects to the top port of the front cylinder.
The hard line should connect to the bottom port on the front cylinder & to the top port on the rear cylinder.
Bottom port of rear cylinder has the bleed screw.

Now the problem: Some early cars had a steel ball under the bleed screw on the rear cylinder, of the front wheel (bottom port). Item 17 in the pic.

If you interchanged the front & rear cylinders, the steel ball would now be on the top port of the front cylinder & would be blocking fluid flow into the rear cylinders.
D

 

[whitworth]

Re: late BN1 brake spring anchor posts

Dave,
On the rear brake cylinders (made in China) the bleed valve is above the brake line, on most cars the bleed valve is the lowest point. Your thoughts on this please.

 

[Dave Russell]

Re: late BN1 brake spring anchor posts

I think it will work either way. You might get better bleeding if the bleed screw is at the higher point since air rises. My BN2 has the bleed screw at the high point.

I think the two holes are machined identically. Just make sure that if the cylinder has a ball valve under the bleed screw that the ball remains under the bleed screw & not under the supply pipe.

Note in above post that I added a pic showing the front bleed screw ball valve, #17.

For the rear, the ball valve is #20 in the previous rear brake pic.
D

 

[whitworth]

Re: late BN1 brake spring anchor posts

I might add that neither of the front brake springs in the Moss catalog fit the grooved posts.

 

[whitworth]

Re: late BN1 brake spring anchor posts

Dave,
Finally made new anchor posts & found a source for the correct springs, everthing fits nice. But if you notice in the dwg. (plate AH. 189. A.) for the front assembly, the springs pull the shoe towards the fixed end of the wheel cylinder. I would think if the spring was pulling to retract the shoe closer to the cylinder piston end this would be a more efficient means. I'm leaving it per the factory manual for now, but makes me wonder.

 

[Dave Russell]

Re: late BN1 brake spring anchor posts

Note that the spring pulls the anchored end of the shoe inward at a considerable angle. Both ends of the shoe actually slide inward & outward a bit as it moves. Each shoe end slides on it's own abutment. If the spring were pulling on the other end, only one end of the shoe would retract, the other end would drag.

Really a rather complex set of movements but it seems to work well when everything is correct.
D

 

[whitworth]

Re: late BN1 brake spring anchor posts

So I guess a dab of the right grease in each shallow groove (opposite the piston end)of the wheel cylinders would help this sliding action. I've already de-burred the ends of the shoes.