Anyone experience a failure where your brakes don't release fully after a stop?
My w11 is doing just that. Not just one but all four are lightly locked up. I can just budge it if I push hard, and the car will move under power but that'll cool the pads quickly.
The flex lines are braided goodridge lines and the hard lines are all in v good shape. Bled the brakes two months ago and the fluid looke v clean.
I haven't had a chance to try cracking a bleeder yet as I'm actually roadside waiting for a flat bed tow.
John
Brakes fail "on" ??
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erictharg
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Re: Brakes fail "on" ??
If it is all four wheels it sounds like a problem with the master cylinder not releasing the pressure when you lift off the pedal. Otherwise I can't think what could be causing it. Midget calipers are pretty robust and not prone to seizing, and the rear drums can always grab if adjusted up too much. But both ends says master cylinder to me.
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Westfield 129
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- Joined: Sat Jun 04, 2011 4:20 am
Re: Brakes fail "on" ??
Master cylinder has a ridge and is sticking on release, or you have a sticky valve. Get rid of it. Save the actuating rod though. You can get a .75" Wilwood Girling type for about $60, or less. That will fix your problem.
It is not worth rebuilding, but if you feel like doing that, you need to use emory paper in a mandrill to finish the inside of the alloy cylinder. Don't use stones. With the price of the cylinders so cheap, it isn't worth rebuilding.
Don't drive the car, as it will get you stuck. Seized master cylinders are common on cars that are not driven often, or spend many months parked. Clean fluid makes no difference.
I suggest new calipers and rear brake cylinders if you have not done those already.
It is not worth rebuilding, but if you feel like doing that, you need to use emory paper in a mandrill to finish the inside of the alloy cylinder. Don't use stones. With the price of the cylinders so cheap, it isn't worth rebuilding.
Don't drive the car, as it will get you stuck. Seized master cylinders are common on cars that are not driven often, or spend many months parked. Clean fluid makes no difference.
I suggest new calipers and rear brake cylinders if you have not done those already.
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jonclancy
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- Joined: Tue Nov 01, 2011 9:30 pm
Re: Brakes fail "on" ??
Just for future info, where would be the cheapest place to get a 3/4 inch MC Stateside, please Jan? Looked at eBay and it's around $75 with shipping (to a US address - mailbox for me).
I think the part number is 260-3374 - these look like single circuit. I thought our cars were dual.
http://www.wilwood.com/MasterCylinders/ ... rList.aspx
I think the part number is 260-3374 - these look like single circuit. I thought our cars were dual.
http://www.wilwood.com/MasterCylinders/ ... rList.aspx
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adamwilkinson
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- Joined: Wed Jun 29, 2011 12:17 pm
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Westfield 129
- Posts: 867
- Joined: Sat Jun 04, 2011 4:20 am
Re: Brakes fail "on" ??
Try Amazon. Usually, they will hook you up with HRP World or one of the Hoerr race parts companies. Today, the .75" Girling type by Wilwood was $41~$46. This has the cast reservoir, just like the Girling type on the car. Keep the rod from your old cylinder in cast it was cut or is a special length. You can also cut the rod on the Wilwood if necessary. PN 260-1304 single circuit.
The 260-3374 is a dual circuit, with a removable reservoir. You can get it for $64.99 (excellent price! From HRP, an excellent company). I am wondering about the bore, as the circuits are split. Maybe a smaller bore might be needed, perhaps .7" rather than .75", as the slightly larger more may make for too high a pedal pressure, depending on the geometry of your pedal quadrant. As far as I know, the early cars were all single circuit unless someone modified the system. If you have two brake lines coming out of the cylinder, you have a tandem master. Hopefully, you get the same size so your brake pedal pressure will remain the same (if that is what you want).
Our cars are SINGLE CIRCUIT. The system has a single tube from the M/C to both brake sets, and is .75". If your car has something different, send me a picture. I might have one new dual circuit sitting on the shelf here that I didn't use (I had good reason) on my RHD car. Or, you can order from Amazon. The price would be better than I would be willing to let my ATE tandem go for, anyway.
I have given up on Ebay and have been using Amazon for the last couple of years with good success. I have purchased several Wilwood master cylinders through Amazon for my last few cars, all at good pricing as above.
The 260-3374 is a dual circuit, with a removable reservoir. You can get it for $64.99 (excellent price! From HRP, an excellent company). I am wondering about the bore, as the circuits are split. Maybe a smaller bore might be needed, perhaps .7" rather than .75", as the slightly larger more may make for too high a pedal pressure, depending on the geometry of your pedal quadrant. As far as I know, the early cars were all single circuit unless someone modified the system. If you have two brake lines coming out of the cylinder, you have a tandem master. Hopefully, you get the same size so your brake pedal pressure will remain the same (if that is what you want).
Our cars are SINGLE CIRCUIT. The system has a single tube from the M/C to both brake sets, and is .75". If your car has something different, send me a picture. I might have one new dual circuit sitting on the shelf here that I didn't use (I had good reason) on my RHD car. Or, you can order from Amazon. The price would be better than I would be willing to let my ATE tandem go for, anyway.
I have given up on Ebay and have been using Amazon for the last couple of years with good success. I have purchased several Wilwood master cylinders through Amazon for my last few cars, all at good pricing as above.
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jonclancy
- Posts: 944
- Joined: Tue Nov 01, 2011 9:30 pm
Re: Brakes fail "on" ??
Thanks all.
I'll post up a pic tomorrow.
I'll post up a pic tomorrow.
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jonclancy
- Posts: 944
- Joined: Tue Nov 01, 2011 9:30 pm
Re: Brakes fail "on" ??
Westfield 129 wrote:
>
> Our cars are SINGLE CIRCUIT. The system has a single tube from the M/C to both brake
> sets, and is .75". If your car has something different, send me a picture. I might
> have one new dual circuit sitting on the shelf here that I didn't use (I had good
> reason) on my RHD car. Or, you can order from Amazon. The price would be better
> than I would be willing to let my ATE tandem go for, anyway.
>
I suspect all UK cars are not. Mine is an AP dual MC, as pictured here:
http://i94.photobucket.com/albums/l96/j ... MG2565.jpg
A remote reservoir would be a good mod, I think. Especially if you're racing and bleeding the brakes before each race.
>
> Our cars are SINGLE CIRCUIT. The system has a single tube from the M/C to both brake
> sets, and is .75". If your car has something different, send me a picture. I might
> have one new dual circuit sitting on the shelf here that I didn't use (I had good
> reason) on my RHD car. Or, you can order from Amazon. The price would be better
> than I would be willing to let my ATE tandem go for, anyway.
>
I suspect all UK cars are not. Mine is an AP dual MC, as pictured here:
http://i94.photobucket.com/albums/l96/j ... MG2565.jpg
A remote reservoir would be a good mod, I think. Especially if you're racing and bleeding the brakes before each race.
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erictharg
- Posts: 680
- Joined: Thu Jan 29, 2009 7:50 pm
Re: Brakes fail "on" ??
I can confirm that topping up that reservoir is a real pain! Might just be reason enough to move to dual cylinders...
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Westfield 129
- Posts: 867
- Joined: Sat Jun 04, 2011 4:20 am
Re: Brakes fail "on" ??
The LHD early cars were all supplied single circuit where the early Westfield fabricated pedal quadrant was used. Later kits used the Spridget pedal quadrant, and those got tandems if the donor had them. Note that those cars are now 30 years old, and have been through a few owners and modifications. My car, at #129 ('82~83?), is nearly the end of the line, and still had the fabricated hanging pedal quadrant.
I imagine that the RHD cars were also single circuit, but fitting a tandem would be no problem with the firewall mounting, and floor hinged pedals.
My RHD has twin single circuits with a Westfield bias bar, replacing the tandem. I can tell you that topping up the cylinders is EASY with the dual cylinders and remote reservoirs from Wilwood. However, if you change the fittings at the tandem, you can install a remote cylinder if you want to save a few quid. However, the precision and firm pedal of the .7" dual master cylinders is really quite nice. Finally, I can heal/toe properly. The expensive part of the conversion is the cost of the brake pedal from Westfield. The master cylinders are inexpensive, and if you don't go for the "compact" type, reservoirs and reservoir tubing come with the longer type, saving more money again. While they look a little long for the installation, they do fit, easily. I would terminate the brake lines in flexibles with fittings. This makes the installation much easier, as well as making removal and installation of the master cylinders very easy.
In any case, retrofitting a tandem would be easy to do on a LHD car, as the mounting is standard for both. Of course, the brake lines would need to be rerouted (mine has a union on the RH side of the fire wall), and it would probably be a good idea to install a proportioning valve in the rear circuit. I have considered installing a tandem. Maybe when I am finishing the cosmetics...
Send the pic direct to my E mail.
I imagine that the RHD cars were also single circuit, but fitting a tandem would be no problem with the firewall mounting, and floor hinged pedals.
My RHD has twin single circuits with a Westfield bias bar, replacing the tandem. I can tell you that topping up the cylinders is EASY with the dual cylinders and remote reservoirs from Wilwood. However, if you change the fittings at the tandem, you can install a remote cylinder if you want to save a few quid. However, the precision and firm pedal of the .7" dual master cylinders is really quite nice. Finally, I can heal/toe properly. The expensive part of the conversion is the cost of the brake pedal from Westfield. The master cylinders are inexpensive, and if you don't go for the "compact" type, reservoirs and reservoir tubing come with the longer type, saving more money again. While they look a little long for the installation, they do fit, easily. I would terminate the brake lines in flexibles with fittings. This makes the installation much easier, as well as making removal and installation of the master cylinders very easy.
In any case, retrofitting a tandem would be easy to do on a LHD car, as the mounting is standard for both. Of course, the brake lines would need to be rerouted (mine has a union on the RH side of the fire wall), and it would probably be a good idea to install a proportioning valve in the rear circuit. I have considered installing a tandem. Maybe when I am finishing the cosmetics...
Send the pic direct to my E mail.