6 replies to this topic

[Parity]

OK, so it looks like I've managed to make the easiest job into a project. I purchased rebuild kit from NAPA (PN #1525). Replaced the seal but cannot get the dust boot in. I lubed it with brake fluid and slipped it over the piston so just the rear flange area which goes into grove in caliper is showing. It seems like it's simply too large and will not fit. If I get it in 90% around, there's way too much excess material to slip in. Not going to happen. I ended up tearing one and installed it without the piston. It ended up with about 3/8" overlap so I started thinking I had the wrong part even though the seals went in easily. I purchased a second set from Rock Auto which turned out to be NAPA brand. Same thing. I reused the old dust cover on one side but the other side is too far gone to use. The diameter of the flange if definitely larger in the NAPA seals than in the old ones.

 

I have watched "how to" videos and did the rears with no problem. Is there some tribal knowledge I'm missing? Maybe the NAPA brand doesn't fit right?

[steveracer]

You're stretching the boot by treating it like a zip lock bag. 

 

You have to put it in the groove, then only push it straight into the groove without moving your finger left or right, then lift your finger to the next spot and push outward only. If you end up with a "bubble", just push in the middle of it, when the next spot "bubbles", push it in then next until it equalizes it self.

 

To get the boot over the piston, hold the lubed piston against the installed boot and gently use air pressure into the hose fitting to inflate the boot up over the piston. It will likely take a few tries to get the pressure dynamic just right, but it will slip over the piston.

 

Also, buy Mazda kits.

 

Hope this helps.

[Ron Alan]

From memory...boot over the very end of the piston(little brake fluid on all items)...the portion of the piston that goes in first. With the boot hanging off the end of the piston work it into the caliper groove. Once in carefully begin to push in the piston past the boot and internal seal. When the piston goes all the way in, the boot will pop into the groove on the end of the piston. I think this is how i've done it with no problems. 

[Tom Hampton]

What Ron said, is what worked for me.

[Duane Polsley]

What Ron said is correct

 

However I got some aftermarkets (NAPA I think) and both the o-ring and boot were slighty to big. Only used Mazda since

[marcusmazza]

Paul,

 

I used the Dorman brand pistons, seals and boots when I rebuilt my 1.6 calipers last year. No issues. I thought the Mazda stuff was also cheap aftermarket Chinese stuff, just like the rest of it. There was a thread about this some time ago.

 

Marc

[Parity]

Got my Mazda parts in today and it went together easily. The NAPA seals are much bigger and almost look like they're designed for a different piston. Now I know what they mean by "NAPA no how".