Datsun Roadster Forum-311s.org

I took apart my brake master cyl. and the kit I had for it is smaller. Now I cant drive the thing for a while. Anyone know a part # or where I can get the right kit for the master cyl.? It is the dual one.

Thanks,
Joaquin

It has been my experience that the master cylinder does not take well to rebuilds. I would suggest buying a new one if you can afford it. Brakes are not something you want to gamble with.

Just my opinion.

Alexi

Thats true about the brakes, where can I get a replacement for a fair price? Or something that will serve me good.

Joaquin

Can't we use 280zx master cyl? If so, any NAPA will have one...

DELETED

Yes, but the the 1975-77 280Z 7/8" is what's suggested for the early roadsters doing the Volvo brake conversion. The main problem appears to be the standard vs. metric threads, although I cannot believe there isn't an adapter for that.

If you go with the original master they are about $215 if nissan can locate one, I am sure one of the vendors have some. I am not sure but I believe if you change the bore size your brakes may not act like they should. Maybe someone can verify this. I have heard of problems if using the wrong size bore.

Alexi

I have heard the 510's or something like that will work, but you have to cut, or change the fluid cups from the roadster to the 510 one so it wont hit on the hood. Anyone know about this??

Joaquin

DELETED

7/8 is also the size for the PL410/PL411, so you could probably make one of those work (may need to swap rods). If you can't find a new m/c or the price is too high, contact White Post www.whitepost.com. They resleeve and rebuild hydraulic parts, probably will cost less than $215 to do our m/c's and will be more durable (able to be rebuilt).

I'm sorry for going off topic here but am I the only one who thinks that alfred183's avatar picture is "interesting?" GT4 image? Or just someone havng a GREAT time in their roadster?

Looks like GT4, Never driven the roadster, but the game is good.

Joaquin

The 7/8" master for a 70's 240Z will work, you just have to push harder to get the same amount of braking. Not optimal, but way safer than using a 5/8" in a 7/8" application and having to pump the brakes!

You have to modify the cups, the bolt spacing, the actuator lever and convert the hydraulic fittings to metric.

A bit of work, but if you are planning to upgrade to Volvo or other higher fluid displacement brakes in the future, the price cannot be beat! I think you can get all of the parts for the conversion, including the master and loaded calipers for the same price as the Nissan master...

As always, working on your brakes means you are taking your life in your hands as you work. Be safe and get professional assistance!

Joaquin:
I have a used one that I can take off of a parts car. Sam

I've been through this too with the brakes and the clutch masters. Fortuneately, I own 510's too. Most parts places have no idea what a Datsun Roadster is, it's like they never existed in the first place. What I do is have them do a search for 510 parts, as many times they will interchange with the Roadster. After reading the posts on this topic I called Carquest and had them do a search for a 1971 510 brake master cylinder. He found one in their Seattle warehouse for $53.10 exchange. My 71 510 and 70 Roadster are parked side by side outside and the brake and clutch masters are identical. So think outside the box when looking for parts and perhaps you can save yourself some money and time.

Good luck!

Scott