brakes and fuel

[scottmars]

Morning all,

I have finally purchased a 412 after selling my last over 30 years ago. The one I have bought has not left its garage since it went in in 1990 with a leaky brake master cylinder. It hasnt even started since around that time.

Its a bit crusty as you can imagine but not too bad .

My first job is I want to get it movable under its own steam so want to change the brakes and all fuel lines.

I understand there are 2 types of front calipers - I think i have both sets in the spares - are the seal kits and pads interchangeable or are they unique to each type of caliper? how do i know which i need?

I believe the m/c uses 19mm seals from a beetle ? is that correct ? which model?

Flexi hoses also I understand are beetle ones ? again which ones ?

Rear shoes - beetle ? again which model?

and lastly for brakes - wheel cylinder - any ideas re these?

for the fuel lines - what do i need to replace these?

loads of questions i know but all related . I want to order some bits and get stuck into it. Im in the UK

Many thanks

Scott

[raygreenwood]

Greetings! Welcome back!

Ok.....the rear brake system in its entirety is type 3. Every single part in the rear braking system is type 3....even though it has a totally different rear trailing arm and stub axle design.

The rear wheel cylinders, brake shoes and hardware kit are late type 3.
Beware and be careful with other items though.....like never lose or damage the rear outer bearing cover. While it looks identical in every way on the outside to type 1 and 3....probably the same casting.....it's machined totally different internally and is unique to type 4 with a type 4 part #.

If the rear drums are still original German....try to keep them at all costs. What is available aftermarket are cast, one piece Brazilian made....and are miserable and 95% are machined out of round.

The front and rear brake hoses "should" be the same part # 113 611 775.

There are "some" type 1, 19mm master cylinders whose seals will fit in type 4.....but it's safer to use late type 3 master cylinder seal kits. Typically if you can find a master cylinder seal kit for a type 3 that is the same BRAND as your master cylinder.....either ATE or FAG.....it's ideal. But that's hard to find these days and generally you can get away with mixing brand parts.

Most new MC seal kits are an aftermarket universal seal that work well enough on most brands.

Bear in mind.....you want the piston seals, the brass flap valves, the fluid inlet rubber grommets, the 6mm bolt and copper seal from the type 3 kit.....BUT NOT THE PISTONS. Piston spacing is unique to the master cylinder casting and type 3 will not work in a type 4 cylinder or vice-versa.

The change in front calipers, rotors, pads and stub axle was August of 1972. So the early, thinner pad and rotor with a different caliper offset for the 411.....ran from 1968 UP TO August of 1972. After August it was all 412.

The calipers early and late use the same o-ring seals between the caliper halves and the same internal piston seal size (they are both 42mm piston) and they use the same anti-rotation plate outside.....BUT....they actually have different pistons and use different outer boot seals.

So.....the late calipers for 412 are the exact same ones used on Porsche 914 FROM/After August of 1972.....so if you cannot find the kits at VW shops.....drop into a Porsche shop.

The early pads were roughly 14.8 to 15mm thick and the later ones you want are roughly 18mm thick. Ray

[scottmars]

You are a star Ray , many thanks , when you say late T3 , what year from ?

Any idea re the fuel lines ? do I just need injection capable hose ? any particular size?

[raygreenwood]

[Lars S]

[scottmars]

Many thanks Ray , I will get that ordered too .

Lars , thanks too , I didnt know about the self adjusting being different . Ive ordered late Type 3 , will see if it fits at the weekend.

[Lars S]

[scottmars]

Hi Lars , thanks , thats something i can do . will check at weekend.

[scottmars]

Just as a wee update , I have managed to strip and rebuild the front calipersand have now replaced the front pipework . next up is removal of the master and rebuild that before i venture to the rear brakes , hopefully all done in the next few days then i can start replacing the fuel lines with a view to starting the car .
as an aside , the car doesnt have a battery , what one is required? i obviously dont want it catching on the underside of the seat but cant remember what was in my last 412 all those years ago

[Lars S]

Glad to read that you succeded with the fronts!⁷

Regarding the battery there was a thread on it not to long ago:
https://www.thesamba.com/vw/forum/viewtopic.php?t=763456&highlight=battery

In any case make sure you protect the poles, on a 411I had one of the seat control wires snap off under the seat, shorted to the positive and started an under seat fire!

Keep up the good work!

/Lars S
_________________
Porsche 914 -72, Bahia Red daily driver
VW411 2-d -70, White, sold
VW412 4-d, -73, Gold Metallic, daily driver
Suzuki T500, -69, Candy Gold, sold
Suzuki K50, -77, Black, daily driver
BMW R69S -69, White, sold
Husqvarna 118cc, -47, Black, Sold

[Lars S]

Glad to read that you succeded with the fronts!⁷

Regarding the battery there was a thread on it not to long ago:
https://www.thesamba.com/vw/forum/viewtopic.php?t=763456&highlight=battery

In any case make sure you protect the poles, on a 411I had one of the seat control wires snap off under the seat, shorted to the positive and started an under seat fire!

Keep up the good work!

/Lars S
_________________
Porsche 914 -72, Bahia Red daily driver
VW411 2-d -70, White, sold
VW412 4-d, -73, Gold Metallic, daily driver
Suzuki T500, -69, Candy Gold, sold
Suzuki K50, -77, Black, daily driver
BMW R69S -69, White, sold
Husqvarna 118cc, -47, Black, Sold

[raygreenwood]

[scottmars]

Thanks Gents ,
The pistons were well stuck - car been off road for over 30 years , a bit of heat and compressed air eventually freed them . they were actually quite good when stripped down and thoroughly cleaned
When I had my beetles I always put a rubber mat over the battery to prevent a short, I can not remember what I used on my 412 but I will do something.

[Pepperbilly]

Welcome back to the type 4 community! It is always good to see another to be saved.

The original batteries were not fully covered. Some batteriies actually had just a small 4 post plastic cover for the positive terminal only. Negative post was exposed.

Bill

[scottmars]

Thanks Bill , I will fashion something for peace of mind.
After doing the inboard rear brakes & diff seals on my XJS I gad forgotten how much more accessible these cars are to work on.