Disc brake conversion problem

[P_Vilefort]

Did you adjust the free pedal on the brake master cylinder? That is the amount the pedal push rod moves before it moves the brake master cylinder piston. If not adjusted properly you will never get the brakes bled or the master cylinder pedal hard.
Disc brake master cylinder diameter is 19.05mm or 0.75 inches.

[P_Vilefort]

I have a '72 Super with OEM front disc brakes rear drums and no residual valve in the system. This is a European Super and it came with factory ATE front discs. When I replaced flex pipes that were 49 years old and some of the rigid pipes I gravity bled the system and adjusted the free pedal travel. Did fronts first and had a hard pedal. most of the time people forget about the pedal free travel. If not adjusted properly the fluid will not return to reservoir. I also used MOTUL DOT 5.1 synthetic brake fluid. It has a lower viscosity and makes gravity bleeding a snap.. It also has a higher boiling point and doesn't absorb water as easily as other brake fluids. It is NOT a Silicone based fluid.

[P_Vilefort]

Bruce36
Where do you get your information? It is wrong. OEM disc brakes were available starting in 1968 and all European Super Beetles came with front discs regardless of engine size. You could even get a 1200cc engine in the Super and it came with optional disc brakes. Anything over the 1200 were automatically installed with ATE or Girling front discs. Early Super Beetle production (1971) came with Girling single pin pads and the ATE had dual pin pad retainers. Karmann Ghias came with a larger caliper similar to the 411 models. Caliper bracket uses a different bolt pattern on the 411 and Karmann Ghia caliper attachment; 75mm center-to-center I think. The Super Beetle uses a caliper bolt pattern that is about 55mm center-to-center. I have a Super built on May 11, 1972 for the home market and it is a 1302 with ATE 11 inch diameter front discs (same physical size diameter and thickness as the Jaguar front disc brakes). I compared my VW front discs to my brother's XKE front disc brakes with the same diameter and thickness.

If I could post pictures I would post the pages from the 1302-1303 Kafer parts microfiche where you can see that European production was disc brakes. USA didn't get them due to cost and competition in American market with the Japanese cars.

Set the brake pedal free travel properly and your bleeding problems will disappear. I learned this back in 1971 when I was having the same problem on my 1951 Studebaker. Set the free pedal properly and bleeding worked right away with a solid pedal.

[P_Vilefort]

If you are looking for the correct MC for Super Beetles use the Dorman M96382 Brake Master Cylinder. If you look at it on Amazon you will notice that the connectors for the reservoir hoses are horizontal. They need to be like this especially for the forward most position. If they are no horizontal they will leak where they fit into the rubber fitting. The horizontal fitting will not strike the underside of the body. The ones at a steeper angle will hit the floor and you will not get them to seat in the rubber bushing. I have been there and from my personal experience is that the nylon fitting has to be horizontal. I used the fittings from my original factory MC.
I am repeating myself again. The bleeding problems you are having is only related to the brake pedal free travel. You need about 3 mm of free travel in the piston rod before it strikes/hits the inside of the MC piston. If it is less than 3mm you will never get the air out of the system. Do one bleeder at a time and put a small tight fitting vacuum hose on the end of the bleeder. Submerge the other end in a glass jar with brake fluid at the bottom. Turn bleeder a 1/4 turn. Watch for bubbles rising in the brake fluid in the bottle. If you do this by gravity, check the reservoir and refill it frequently. I discovered MOTUL Synthetic brake fluid and it's lower viscosity will help with gravity bleeding. It is great stuff and is not a silicone based fluid. You want MOTUL DOT 5.1. You can get it on Amazon. I got the three bottle special and still have a full unopened bottle.
If you are replacing the hoses from the reservoir use hoses for a water-antifreeze automotive cooling/heater system. The inner lining is compatible with glycol solutions and brake fluid is glycol chemistry. Anything else will disintegrate over time. I think you will need 1/4 inch ID heater hose.

[Bruce2]

Bruce36
Where do you get your information? It is wrong.

You're the one with the bad memory. What you posted doesn't even make sense.

OEM disc brakes were available starting in 1968

Disc brakes on Beetles and Karmann Ghias actually started in 1967 in Europe with the introduction of the 1500cc engine. German law says all cars with an engine that makes more than 50hp requires disc brakes. Since the 1500 was advertised at 53hp, it had to have discs.

...and all European Super Beetles came with front discs regardless of engine size.

Nope. Only cars with 1500 or 1600s got discs as standard equipment.

...and all European Super Beetles came with front discs regardless of engine size. You could even get a 1200cc engine in the Super and it came with optional disc brakes.

Make up your mind. Were discs standard equipment or optional?

You could even get a 1200cc engine in the Super

Nope again. If you bought the cheapest base model of standard Beetle, it came with a 1200 cc engine. If you bought the cheapest Super Beetle, it came with a 1300 cc dual port engine. The 1200 wasn't offered for a Super. My theory for that is that if they put a 1200 in a Super, because of its higher weight, it would be the slowest version of the Beetle. But it would cost more than a standard Beetle with a 1200. So to even out the performance, the Super got the slightly larger 1300.

Anything over the 1200 were automatically installed with ATE or Girling front discs.

Correction: anything over the 1500 automatically came with disc brakes.
If you were to order a car from the factory, you could order discs on any car with a 1200 or 1300, but that would be a special order car.

Karmann Ghias came with a larger caliper similar to the 411 models.

Wrong again. A Karmann Ghia came with the same disc brakes as a Beetle of the same year. The Karmann Ghia never got the larger Type 4 discs and calipers, even to the end of production in 74.
The Type 3 story is different. The first Type 3s with discs came with rotors and calipers that were the same as Beetle and KG, but just before the end of production, Type 3s came with larger Type 4 discs and calipers.

Caliper bracket uses a different bolt pattern on the 411

Hurray! Finally a correct statement. The Type 4 caliper has a slightly larger bolt spacing compared to Type 1. Type 1s never got the larger Type 4 brakes.

[H2OSB]

I don't mean to pile on, but EVERYTHING Bruce said is what I've heard and understood since the mid-90s. I could always be wrong, and my knowledge is limited to Super Beetles (I'm one of the two guys who stated SuperBeetles Only! in the late 90s), but I'm pretty certain he's correct.

H2OSB

[P_Vilefort]

I have the build sheet for my '72 Super. It has the 1300cc engine and there is no additional M code for the disc brakes. It is listed as it was built but if it was optional equipment then there would be an M code, or I should say, there was supposed to be an M-code.
I have a friend in Germany who is also on TheSamba and he told me that his Super Beetle was his mother's and it has the 1200 engine. A distinguishing feature is the lack of a crash pad that appears on all of the other 1972 vehicles.
If you look in the 1302-1303 Kafer microfiche, there are no listings for front drum brakes being installed on any of the 1302 or 1303 models that remained in Europe or went to Japan. Only vehicles exported to North America show front drum brakes. Please explain the discrepancy in the microfiche parts listings.

[P_Vilefort]

In addition, take a look at a 1972 European Super Beetle and Beetle Brochure and you can see what combinations were available. Very little of the items in the brochure were available in the USA or North America. In Europe cloth upholstery was popular but it seems it wasn't available in the USA. Some of the combinations you see in restored cars were never available when the car was new.. For instance, if you bought a Super in Germany and it was Marina Blue it only came with Lapis Blue upholstery in either a 10-wale corduroy fabric or a basket weave vinyl. Not one of the other options were available. Door panels were only available in the Dark Blue vinyl. I am not sure what the pattern in the vinyl was called. By pattern I mean the name of the leather pattern.
My car was driven for two years and then spent the next 38 years in closed covered storage. At present it has only 53,046km on the odometer. It had, until recently, the original dated Fulda flexible brake lines in the front. The rear ones are still the originals but with the engine out for oil seal and motor mounts replacement, I am not driving it.

[P_Vilefort]

H2OSB

What do you mean, Super Beetles only in the late 1990s? I am not sure what year the Super became the body for the Cabriolet,maybe '71 or'72? The later Mexican Beetle didn't use the Super Beetle front sheet metal. The front suspension was the twin torsion bars and trailing arm suspension. I watched the movie about the last Mexican production car and it appeared like the Standard Beetle, except for the directional lights in the bumper, maybe with the same arrangement or similar to the Rabbit front directional lights?

To add additional clarification, I didn't know anything about the Super Beetle until I bought the one that I have that was built for the German market. Every thing I was talking about was told to me from contacts on TheSamba and what I gleaned from what I was told when I was rebuilding my front calipers. I know now that the ATE calipers, though advertised to be 40mm are actually 39mm and the Girling caliper piston will not fit as a replacement unless it is machined smaller or machined from a different material. Even though the ATE caliper is still being made, no replacement parts seem to be available other than the rubber stuff. That 1 mm difference is a real bugger.

[Bruce2]

I have the build sheet for my '72 Super. It has the 1300cc engine and there is no additional M code for the disc brakes. It is listed as it was built but if it was optional equipment then there would be an M code, or I should say, there was supposed to be an M-code.

The build sheet is a poor source of info. If you spend time here and on the Samba, there are many topics where people show their build sheet and it lists an option on their car that isn't there. Or their car has an optional part and it's not listed. Here's an example. Years ago I had a 72 Super that had an Eberspacher gas heater. It wasn't listed as an option on the car! I'm in Canada, and I have seen countless 1302s, and every one had a gas heater. This tells me that VW of Canada ordered every car that way.
If a Super Beetle came with disc brakes, there should be an M code for drums, right? I've never seen such a code.
What country was your car built for?

I have a friend in Germany who is also on TheSamba and he told me that his Super Beetle was his mother's and it has the 1200 engine.

Either your friend's car is a standard Beetle, or it has a 1300. The 1200 was only available in Germany in the standard Beetle. Does your friend's engine have dual port heads or single port?

If you look in the 1302-1303 Kafer microfiche, there are no listings for front drum brakes being installed on any of the 1302 or 1303 models that remained in Europe or went to Japan. Only vehicles exported to North America show front drum brakes. Please explain the discrepancy in the microfiche parts listings.

The microfiche is the spare parts list. It isn't the log of what was available in each country. The microfiche here in North America shows the parts for disc brakes on Super Beetles, but we all know VW never sold discs on Supers in NA.

[Bruce2]

In addition, take a look at a 1972 European Super Beetle and Beetle Brochure and you can see what combinations were available.

The sales brochures are not always accurate. Look at the first brochure for the 1973 1303. On the top rear of the front hood you will see the bright aluminum VW badge. Have you ever see one on a car?

For instance, if you bought a Super in Germany and it was Marina Blue it only came with Lapis Blue upholstery in either a 10-wale corduroy fabric or a basket weave vinyl. Not one of the other options were available. Door panels were only available in the Dark Blue vinyl.

That is only true for 1972. The 71s weren't available with blue interior, only black if it was vinyl (on a Marina blue car).

[Bruce2]

H2OSB

What do you mean, Super Beetles only in the late 1990s?

Web site. I believe it was www.superbeetlesonly.com

Every thing I was talking about was told to me from contacts on TheSamba

There's your problem. There are a lot of very knowledgeable people on the Samba. And there are a lot of dummies.

I know now that the ATE calipers, though advertised to be 40mm are actually 39mm and the Girling caliper piston will not fit ...

The bore in the caliper is 40mm. The pistons are smaller.

[Bruce2]

If you look in the 1302-1303 Kafer microfiche, there are no listings for front drum brakes being installed on any of the 1302 or 1303 models that remained in Europe or went to Japan. Only vehicles exported to North America show front drum brakes. Please explain the discrepancy in the microfiche parts listings.

When I went to Germany in the early 90s, my trip was totally focused on cars. I toured factories, visited auto museums, and went to VW car shows. When I was talking to the guys at the shows, I told them I was looking for disc brake spindles for Super Beetles. They laughed at me and said I would never find any. That's when they explained that discs only came on 1600cc cars, and that people rarely bought the 1600 engine in a Super due to the high annual tax for the larger engine. The overwhelming majority of the cars sold there had the smaller 1300 engine, and that meant drum brakes. But by the 90s, people wanted to build cars with very big engines, typically over 2 liters and Type 4. They told me that when you want to modify the engine, you must first upgrade the brakes to discs. Because of the strict rules of the TUV, you cannot use anything other than the factory front spindles. They said every junkyard has a long list of people wanting disc spindles, because it is the "green light" for their project. Without the spindles, you can't build your car.

[H2OSB]

Bruce is correct. SuperBeetlesOnly.com was a very active web site and source of information, started in 1999 by myself and James Dunn, known as Superman. We had some of the most knowledgeable people regarding Super Beetles from around the world including the States, Australia, Japan, the Netherlands, Germany, France, elsewhere in Europe, Brazil, elsewhere in South America, and one guy with a wild track car in South Africa.

Unfortunately, we eventually had issues with the ISP and the site faded away. It was an amazing source of VW Super Beetle info that was constantly corrected and verified by folks all over the world who made sure the information was accurate.

SuperBeetles Only! is still alive and well today and bigger than ever, but as a FaceBook group. Unfortunately for me, I've never been much of a FB person so I don't look in on it much. Ownership of the club has changed hands over the years and there are, maybe, 3 or 4 people who even know who I am relative to the club. Superman dropped off the face of the earth and though I've tried several times over the years, I've been unable to contact him.

That all said, *I* am no expert, but I've seen the information repeated many many times over the years. What Bruce relayed was accurate to my recollection. I do not discount what you stated and you seem quite knowledgeable. However, it doesn't correspond to what I've heard. If disc brakes were that common in Europe, the disc brake spindles for 1302s and 1303s would be easier to find, but they simply aren't. When a pair does become available, they're incredibly overpriced which points to scarcity.

H2OSB

[Ephry73]

Easiest way to get it all out is to use a 50cc syringe and reverse bleed the system. Works for many systems including hydraulic clutches. Nipple should be up and check for kinks on the hard lines.

E


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