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A One Inch Diameter Brake Master Cylinder for the S30 Z Cars

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JoeK    2

I'm working on this swap. New booster from a '78 280z. The pushrod appears to be too short. I the pic below, it is about right where I want it to be, about 12.5mm from the face of the aluminum spacer, but it is only threaded in 2 1/2 turns. I pulled the pushrod out of my old booster and it's the same length.

 

The pictures some people have posted in this thread that show the pushrod, they look different than both of mine. They seem to have 1/2" or more length in front of the nut. Suggestions?

 

post-39558-0-83421000-1457250023_thumb.jpg

post-39558-0-53170000-1457250043_thumb.jpg

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Nigel    5

I started prepping my new Wilwood master cylinder for installation and discovered this...

 

13537748_10154168744276405_3151475508254

 

13537587_10154168744471405_6437625129170

 

The mangled cone fitting by itself wouldn't have been a big deal. I could have swapped in the fitting from my 280ZX M/C. But there's no way I'm trusting the cone fitting to seal in the bore of the M/C with those gouges!

 

I don't have time for this!!!  :mad:

 

Nigel

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Miles    32

Nigel

 

Looks like bad machining by Wilwood.

 

Wilwood seems to lack quality control. I bought  two 1 inch  Wilwood MCs that leaked internally right out of the box. The third Wilwood MC I bought was ok and has been on the car for five years.

 

I recall another member saying that the Wilwood 1 inch MC he bought had a problem with damaged output ports/cones/fittings.

Edited by Miles

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Nigel    5

Nigel

 

Wilwood seems to lack quality control. I bought  two 1 inch  Wilwood MCs that leaked internally right out of the box. The third Wilwood MC I bought was ok and has been on the car for five years.

 

I recall another member saying that the Wilwood 1 inch MC he bought had a problem with damage output ports/cones/fittings.

 

Before I posted, I read through the previous posts and I did find mention of those issues. Very frustrating, particularly with our small sample size. With only a month to go until Z-Con, I really don't have time for this. I'll be livid if the replacement has issues too.

 

Nigel

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Nigel

 

Looks like bad machining by Wilwood.

 

Wilwood seems to lack quality control. I bought  two 1 inch  Wilwood MCs that leaked internally right out of the box. The third Wilwood MC I bought was ok and has been on the car for five years.

 

I recall another member saying that the Wilwood 1 inch MC he bought had a problem with damaged output ports/cones/fittings.

 My MC leaked out of the box too.

 

I'm on my second 1" master cylinder...I have yet to bleed it...I hope all checks out.

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Derek    46

Looks like mine is leaking, too. Crazy that so many have that problem.

 

Did you discover the leak by bench bleeding? I just got my Wilwood master yesterday and now I'm having second thoughts.

 

Thanks

Derek

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Derek    46

Unfortunately, I did not.  It took some driving and hammering the brakes to notice the small amount of fluid leaking from between the MC & booster.  I called Wilwood and am getting it sorted out with a new rebuild kit. 

Thanks for the info. I guess I'll mount it up and hope for the best. 

 

I'm not sure "hope for the best" is a term that should be uttered in a brake forum:)

 

Derek

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Kevinbn7    0

I must not have this posting figured out.  I assume if I use the tab button it sends the post. Sorry about the above two posts.

 

Here is what I have

1971 240Z i purchased from a craigslist add last fall. Over the spring and summer I have been resurrecting this car by going through the suspension, Brakes and drive line. The brakes I am using are the Toyota 4 piston truck calipers with solid rotors. The rear are the 240SX/Maxima on solid rotors. I assume the two are interchangeable as I bought the kit on eBay from Silver mine motors and am not sure what the calipers where originally destined for. The 1 inch Wilwood master that is part of this discussion.

 

I bled everything per Wilwood and simply could not get the pedal from going to the floor. All calipers moved but it looked as if I just wasn't pushing enough fluid to get them all out far enough to clamp the rotors and stop the pedal travel. After a discussion with the Wilwood Tech we decided to swap to another master and try again. Z car depot sent the replacement and away I went. Same issue as before. Cannot get he pedal from going to the floor.

 

At this point i am going to step back and do this as correctly as possible. Eliminate the metric/SAE adapters and build my own lines. Reroute the lines so the port designated with the F actually is managing the front brakes. On this car the front port of the stock master provided the pressure for the front brakes. On the Wilwood master the front port is designated for the rear brakes and the only port that had the rubber duckbill anti reversion valve in it. Wilwood tech line stated that port does move more fluid and is specific to the rear.

 

I bought and installed the 7 inch brake booster from Z Car Depot. Made my own adjustable rod to contact the master. (it is touching but not pushing).  I have as much pedal travel as the threads will allow inside the car. brake hoses are all new. I get fluid at all 4 corners. I've bled bottles of brake fluid through here but don't see much air coming out.

 

One anomaly I want to bring up is on the when I had it hooked up with the rear port of the master providing pressure for the rear brakes the reservoir would lower the level with each pump of the pedal (stopped lowering after about 3 pumps) but when the pedal was released the fluid would be pushed back up into the reservoir like it was spring loaded in the rear system some how. Is this possibly compressed air?

 

One of the above posts brings up the low drag design where the boot pulls the piston back. Is this what is causing the reversion? 

Any thoughts on how to ID the rear calipers would be great. 

 

 

I pulled this car from a barn after 20 years of inactivity. Any other things I should check, clean replace etc? Any and all input is appreciated.

Kevin

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Nigel    5

 

One anomaly I want to bring up is on the when I had it hooked up with the rear port of the master providing pressure for the rear brakes the reservoir would lower the level with each pump of the pedal (stopped lowering after about 3 pumps) but when the pedal was released the fluid would be pushed back up into the reservoir like it was spring loaded in the rear system some how. Is this possibly compressed air?

 

One of the above posts brings up the low drag design where the boot pulls the piston back. Is this what is causing the reversion? 

Any thoughts on how to ID the rear calipers would be great. 

 

 

I pulled this car from a barn after 20 years of inactivity. Any other things I should check, clean replace etc? Any and all input is appreciated.

Kevin

 

You may have the rear calipers on the wrong side of the car and they are not being bled properly (trapped air). The bleeder has to be pointing up. 

 

Nigel

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Kevinbn7    0

Bleeders are above the inlet point but not high spot on the caliper. I can see how air could be trapped

 

I looked at a handful of photos of this install. And this is how it showed. Let me get back in the garage this evening and re configure the mounting.

Thanks Nigel for the lead.post-54233-0-86004200-1501177624_thumb.jpg

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Nigel    5

Bleeders are above the inlet point but not high spot on the caliper. I can see how air could be trapped

 

I looked at a handful of photos of this install. And this is how it showed. Let me get back in the garage this evening and re configure the mounting.

Thanks Nigel for the lead.attachicon.gifIMG_0396.JPG

 

That definitely won't work with them oriented like that.

 

You'll probably need to take them off, put a block of wood in the caliper and hold them with the bleeder pointing up while you bleed them. I was never a fan of these SM kits because of this.

 

Nigel

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Kevinbn7    0

I swapped the rear calipers made the new lines for the master to the switch block, bled the entire system and in a short time my son stated we have a pedal. Thank you Nigel for guiding me to the answer. Again, I'm embarrassed that it was so simple but that's the breaks. I've now driven a 240z that hasn't seen the sunshine.. since I don't know when.

 

Now I start sorting to get it back to a completely drivable sports car.

Kevin

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