I've been working on a 5 lug conversion for way too long and it's really starting to **** me off! Everything should work except I have 2 problems:

1 of the pistons in the front 4-piston calipers is siezed. Is there anything I can do to get it out?
A bleed nipple is siezed as well, other than liquid wrench any suggestions?

Thanks
Nima

 

You think that's a PITA try doing a NA -> TII conversion
6 months and going so far.

Anyways.
Try heat. If you can get a torch on the nipple you might warm it up enugh to break loose.

Now a Last resort for the pison stuck.
Take something nice and stiff like a piece of wood or metal and make sure the other pistons which are OK stay in spot.

Then get a smaller piece of wood/metal and some how mount it in front of the stuck piston. Make sure there is not enough room for the piston to completely fall out!

Then hit the brake pedal slowly and then check if the pressure pushed the piston out until it hit the wood/metal.

The wood/metal prevents the pisotn from flying out of it's place (that == bad) but the one with some room allows the stuck one to move a bit before stopping.

If your lucky it will pop loose. Then spray the **** out of it with wd-40 or something.


Also invest in some PB Blaster. This stuff is a life saver.

 

what about just replacing the calipers?

 

Took me a day. But the car I got the calipers had bran new turbo2 calipers on it. Plus someone had converted my car from a 5 lug to a 4 lug so I was basically returning it to stock it's a 90 GTU.

 

That method sounds good, except that it's siezed in the "out" position I think...my pads are already installed too. Not sure that it'll work but I'll sure give it a try. And as for the siezed nipple, heat has been tried and that didn't work...I'm thinking some patience and liquid wrench and a breaker bar should work.

Damn this thing to hell!

 

if youre going to use the heat method, heat up just the nipple and let it cool down. then try to turn it. should come right out!

 

Is brake fluid flammable? I just used vice grips on mine. Of course it got mangled, but I just replaced it with a nipple from one of the 4-lug setups.

Are you also replacing the proportioning valve and booster from a car that had the 5-lug setup? I learned about that the hard way.

 

No I'm not...should I be? How hard are those to change?

 

Simple to change, the part that sucks is bleeding the brakes. Not hard, but tedious. It'll work with what you have, but I was told that the front to back balancing of pressure wouldn't be right, and the GXL booster is a little larger than the base.

Don't get discouraged. When I did my 5-lug swap, the rear bearings were bad, so I had to get those replaced ($$$$). Then I found out about the p-valve and booster needing to be replaced. Replaced those with used ones, then found out that the master cylinder was bad, so replaced that with new. For some reason, it still leaked. I now have marine-grade sealant on it, and I'm not sure if that's working. Now I found out that one of my rear calipers is leaking, so I'm just going to buy a reman from Mazda (~$130). Super!

 

what good is the 5lug conversion?

 

Nima,

I just bought rebuilt calipers, it saved me the aggravation of trying to rebuild them. Fairly cheap 70/ea.

Be very careful if you decide to pry or wrench that piston out, you will score the aluminum and ruin the piston.

While installing a new bleed valve, don't over torque it, you will strip the threads or you will crush the fitting and have to get a rebuilt caliper anyway.

5 lug conversion gives you 4 piston 10.8" vented disc brakes up front. Compared to the 9 and change inch single piston brakes the 4 lug cars come with.

PaulC

 

Re: booster, it's a hassle, you'll be laying on your back with your head stuck in the footwell trying to get at nuts up under the dash.

I'm not so sure it's necessary though, are you sure?

PaulC

 

That's what I was told by someone who previously had demonstrated great knowledge on these cars. I think it was banzaitoyota.

To get the booster bolts behind the firewall, I would consider that step simple in the whole scope of the 5-lug swap.

Where did you get a caliper for $70? Someone else told me they got theirs for $63, but Mazda told me $130. I want to order this as soon as possible (today!), please let me know. Thanks!

 

I got mine from a local autoparts store. AutoZone IIRC.

Really? everythign else is just a matter of taking it off and putting new ones on.. Fairly easy to get to, just gotta have the right parts. Bolts on easily. Trying to get at those booster bolts is a class one PITA compared to everything else, IMHO.

PaulC



PaulC

 

Well, I had a hard time with the rear, because I did things the hard way. I removed the half shafts from the differential, then (the hard part) wiggled the whole half shaft/hub assembly off the control arm. That diff flange on the half shaft is nearly impossible to fit through the control arm! I then had to take these to a shop and get the shaft pressed out of the hug assembly. This was before I was told about a wonderful thing called a gear puller, that probably would've done the trick.

 

Hmm thanks guys, it seems I didn't do enough research when I started this project. I busted one bleed screw, but I managed to do a decent job of bleeding it through the other bleed screw. I took the whole hub off (with the caliper attached), flipped it upside down (so the functional bleed screw would be at the top), bled it and then reinstalled the whole thing.

I'm only gonna be able to drive the car for about 2 weeks before leaving the country for one year, so I won't be doing all the other swaps necessary.
Let this be a warning to all who are considering doing this swap, it's not as easy as it looks! If all your parts are perfectly functional and everything goes as planned, its not bad. But these parts are 15 years old and are more trouble than they're worth, imho.

Nima