[T3] Rear Wheel Cylinders

[Brent Bottolfson]

My rear subframe is already separated from the pan as I'm installing new 
floorpans off the body.  I'm going to blast/repaint it all anyway and 
will put in new hard lines while I'm at it.

Looks like hones are fairly inexpensive, so I'll just rebuild them.

Jim, I do have a copy of your DOT5 writeup and will be using it when I 
get it all back together.

Thanks,
Brent

On 4/20/11 7:01 AM, Jim Adney wrote:
> On 19 Apr 2011 at 21:45, Brent Bottolfson wrote:
>
>    
>> I want to replace my rear wheel cylinders while I'm doing the rear
>> brakes.  I have a 69 Fastback with 4 lug rear drums.
>>
>> Are all 22mm wheel cylinders the same?  I can find good 22mm German ones
>> for a beetle, but the 361 part number wheel cylinders for a Type 3 seem
>> a bit harder to find.
>>      
> I believe the Type 3 ones are slightly different in length. I actually
> recommend that you simply rebuild the ones you have. Do it ON THE CAR and it
> will be MUCH easier than replacing them. Buy a brake cylinder hone and do them
> in place. Clean up the old parts, which are almost always fine, and you've
> saved time, money, and hassle.
>
> I only remove them if the bleed valves are broken and need to be replaced. For
> that I have to take them off so I can torch them to free up the stump. The
> problem with removing them is 2-fold: If you're not careful you will damage the
> rubber boots, and you are VERY likely to destroy the hard line feeding into
> them.
>
> If you want the maximum in long term service, lube them with some Dow-Corning
> #33 silicone grease and use DoT-5 silicone brake fluid when you're done. I have
> a faq on the DoT-5 if you're interested.
>
> If you find that you need replacements, I have good rebuilt OG Type 3
> cylinders, as well as rebuild kits. I have LOTs of these, but I've never had to
> use one myself.
>
> FYI, the cylinders are actually 7/8" (22.2 mm.) For some reason, master
> cylinders and wheel cylinders, at least in our era, were all in inch
> dimensions, while disk caliper bores were metric (except in the US, where they
> were also in inches.)
>
>