the car i have is a '75 (built in nov-ish of '74). it has the 1.8 engine in it. the calipers on my workbench came off the car. i've rebuilt the back calipers; they're good. the front calipers have me stuck. i've ordered rebuild kits from 2 different suppliers (one a import specialist and on a chain) and they've both come back the same...with the seals too big for the bore on my calipers. i'm stumped. suggestions?

Maybe someone upgraded the fronts. I would shoot some pictures and email Eric at PMB Performance and see what he thinks. He is the gospel AFAIAC when it comes to our cars and brakes.

Brakes are far to important to take any chances. Good luck.

Seals should be bigger that the cylinder the fit in. They have to be lubed and set into the grooves. Old seals have flatten out

Stop ordering kits from RockAuto.

Seriously, a lot of suppliers have in their computer systems (from their suppliers... like $hitty f'n Dorman kits) the wrong information and they sell you 48mm kits by mistake. Did I say a lot? I meant A LOT.

You can use 42mm kits from early cars or even 42mm kits from 1984+ 911 Carrera rears but, the best kit is the 411.698.471 A. The "A" is extremely important. These will have the integrated dust cover clips in the boot and they will fit snugly over your slightly smaller late model piston tops.

the kit was ordered from a specialty import place. they sound like they know what they are talking about. so, here is a pic....i don't think this'll work. the old bore seal is sitting i-n-s-i-d-e the new one to illustrate the difference in size...so...WTF?

Click to view attachment

Jim, stop buying parts from those "specialty" import places. They don't know crap about your car and even less about the parts that go on it. Buy from a place that specializes in 914s or at least Porsches'. When it comes to brakes, one call to Eric will get you everything you need and it will be right the first time.

That was my biggest realization after joining this site. Using google to source a 914 part is a fairly terrible idea. You look at some of these parts descriptions and it will say it fits Porsche 914 70-76 and then list seven other cars from different manufacturers that it fits too. Using the vendors here will get you EXACTLY what you need the first time, often at near cost (just about every vendor has a day job too) I go to online shops as a last resort or if I need a brand new part from a supplier.

-Ross

These are not Brit cars. When you order parts from the chains they often have what they think is the correct part only because the computer say's so. When you order from a a guy or business that actually builds and drives these cars you will get the parts you need. And unlike Moss Motors the parts will be top quality not like some of the stuff I bought for my British cars from them that kind of look like the part I needed...

Check the members vendor section. Several good sources there.

You say the "front calipers have me stuck" but you show a picture and the seal from a rear caliper...

Your rear caliper seals should be 33mm and your fronts are 42mm. You'll also want to take that adjuster out and make sure you put the seal on that. That is the single most determining factory for a rear rebuild. That adjuster shaft seal will harden and crack with age causing a leak. Did your kits come with seals for that?

hmmm. i didn't pull the calipers off of the car myself and maybe that is the problem. i may be confused back to front...maybe i have 4 kits for thof the sort for one end and not the right kits for the other end...whichever end is which. i've an evening obligation here and will check when it gets to be "dad's garage time" later tonight....stand by for the announcement.

DING! DING! DING! i figured out the problem...my old nemises: operator error! the picture gave me away and eric nailed it...i mixed up the front and back bits and their respective rebuild kits. got it now. i now have 3 calipers completely rebuilt and will do the fourth tomorrow night.

If you have not read the tech article at Eric's site yet, then you will have problems with the rear rebuild.
It is a daunting task even with his instruction (which is excellent).

http://www.pmbperformance.com/page/page/1925687.htm

I am fairly skilled at these things (READING instructions and working with detail tools), and when I was completely finished with the whole process, I concluded the same as Eric: Pay him to do it unless your time is worth less than minimum wage, because I spent a few weeks getting mine done right.
I am sure by now that he can do the work and get the plating done in less effort than for me to read his article and do a few google searches for local platers or caliper paint.

Stu