xblazinlv

OK.....here's the problem.

We couldn't get it to come out, not even with a puller from autozone (which we broke attempting to pull it out) so we used a drill bit and drilled most of it out. The only problem is that for some reason the drill bit only smoothed out part of the hole, so now at the very end there is a little lip of old pilot bearing left. So we attempted to chizzle it out, to no avail.

From there we put in a new bearing and just smacked it in with a mallet.... BIG MISTAKE. All we accomplished is that we bent the new bearing and it seized up and won't spin. So onto the next problem....

I can't seem to find a drill bit that is the right size to fit in the hole and smooth it out so the new bearing I got and seal will go in. I just need to smooth out the hole and I'm set. Only problem is I'm ultra paranoid about messing up the hole, as it is I think the front section of it is about 1mm too open now as we used a sandpaper bit to smooth it due to some flaky metal being left after drilling out the old pilot bearing.


I swear this is an absolute nightmare, I don't want to mess up the hole because that means pulling the motor AGAIN and getting a new crankshaft, correct?

Does anyone have some insight or know what size that stupid hole is so that I can get the right size bit to clean it out? I've gone everywhere that sells bits and the hole is just a bit bigger than most bits I could find at Home Depot or Lowes. I'm going to try Harbor Frieght as I'm sure they'll have something big enough.

Why the hell did Mazda have to use a damn pilot bearing. I haven't seen one on any newer model vehicles, I just don't see the point/reason for using one.

I'm not a transmission expert by any means, and after this experience, I'm ready to take it to a professional. I can't believe this is such a bitch.

Now once I get this hole taken care of and I can get the new bearing it, is there any special method of making sure I get it in ok?

Do I need to grease the outside of the bearing or the inside? Does the seal just sit in front of the bearing?

OK that's my rant/question of the night..... thanks in advance for any help.

alexdimen

iTrader: (13)

i wouldn't use a drill bit, it's kind of like drilling sheet metal that already has a hole in it... it can easily seize and you could really mess up the e-shaft if you went askew or slipped. use an air tool/dremel with a skinny bit to go through the pilot bearing inner shell and weaken the outer shell. work it through carefully and you should be able to slowly destroy it and then pry it out.

as far as grease goes, work it well into the bearing before putting it in. i put a little more grease in there before i put the trans on too, just so it has some backup. the seal goes outboard/towards the trans. of the bearing.

xblazinlv

Well that's the thing, 99% of the old pilot bearing is destroyed / out......we used a drill bit but now the hole still isn't smooth. So do you think using a dremel would help to smooth it out and get the last bits of the old bearing off the walls of the hole so the new one can slip in?

so the seal just goes in after the bearing then correct? It doesn't look big enough to cover it up, it looks around the same size as the bearing it self. Just checking to make sure I do this right.

RotaryResurrection

iTrader: (8)

I have an actual pilot bearing puller, but half the time it won't get them out...the arms bend instead of gripping.

SO I just take a die grinder and grind all the way through the thing. Yeah, I get into the shaft just a little...doesnt hurt anything. Once I am all the way through in one spot, I take a strong screwdriver or chisel and just break the remaining part in half, and pull it out with pliers. Then use a magnet to fish out fragments, and finally hit the cavity with a lot of brake cleaner and compressed air to clean it out. Now the new one installs fine.

Rocking Rotary

iTrader: (14)

I had one spin on me inside the esentric shaft. I used a small grinding bit and a air ginder and slowly worked the shell of the bearing down. Then used a close fitting socket to crush the shell and removed it. It was a nightmare.

When you seat the bearing seat it a 1/4 in below the beveal on the esentic shaft. You must grease the bearing inside and out. Just tap it in with a close fitting socket. Then seat the seal on top and with the socket tap it in and it should be flush with the beveal on the esentric shaft.

Good luck you will need it, just take you time be carefull and you will get it.

dgeesaman

iTrader: (7)

The important thing about Kevin's approach is that it damaged the shaft surface but only in a small portion of it. Drililng it out entirely is a Bad idea because you'll scuff/cut/alter the entire inside of the bore, and the new bearing will 1) never mount straight and 2) may spin under load and eat the bearing.

When you get that piece of bearing out, please inspect the bore very, very closely and use a small grinder tip to cut off any high spots. If you have altered the bore surface beyond, say, 30% of it's area, it may be fubar'd. The fit of the pilot bearing must be that precise.

Drilling stuff out is not bad when the metal you're drilling is softer than the surrounding metal, or when a little extra clearance won't hurt anything. But bearings are hardened steel, probably much harder than the e-shaft bore, so I am concerned that as soon as it breaks thru one side of the bearing race the bit will tend to cut more there and start removing shaft metal instead of the rest of the bearing race. Especially since you don't have it in a drill press or milling table.

As for the tool to use, I bought a used Mazda pilot bearing puller and I've had great success with it. Whether it's a Mazda tool or the Autozone tool, it's critical that the grabbing lip of the puller is not worn. The arms will bend in and pull free every time, and make it that much harder for the proper tool to work. IME 90% of the Autozone pullers are damaged to the point of being worthless.

Dave

blacksi

Never actually seen a mazda flywheel but if like any other one, couldn't you just remove the flywheel and use a socket/punch to knock out the pilot bearing?

GARCO MOTORWORKS

blacksi, the bearing is pressed into the E shaft and not the flywheel .I use a Dremel to cut them out . The job should take about 2 to 3 minutes .

rotorbrain

grind it. . . the way to go. . . just go slow and watch it carefully. when the metal gets thin, you can pry it out a little bit. . . sometimes. the key is to take it slowly. . . minimizing any scarring of the shaft.

xblazinlv

So exactly what bits should I use on my dremel to cleanup the hole / smooth it out. I'm hoping we didn't get into the shaft too much, I just think a piece of the old bearing is still stuck to the walls of the shaft because the new bearing won't go in without a lot of force and I believe that's how the old one was ruined.

xblazinlv

Maybe just the sand paper bit would be best to finish cleaning the hole and smooth it out a bit?

RotaryResurrection

iTrader: (8)

You're seriously overthinking this. Just take a stone, either on a dremel or a die grinder. Pick a spot on the bearing and grind straight through that one spot. All the way through the needles, retainer, and the hard outer race. Check every so often to see if you've penetrated the outer race yet...blow it out with air, and look to see if there is a small "seam" visible where the race ends and the shaft starts. Once you get through the entire race, front to back, you'll have a "seam" about 1/8" wide. Break the remaining race in half and pull it out. Clean it up and you'll have about a 1/8" spot in the inside of the shaft that you ground into...this will not hurt ANYTHING, as you still have 95% of the shaft interior to maintain the new bearing's position. You dont have to do any sanding, smoothing, grinding, etc. if you do it as I described...just blow it out and use some brake cleaner to get all the metal out, and pop in the new bearing.

xblazinlv

That's the problem though, the bearing is already out. The part of the shaft I'm talking about is where we destroyed what was left of the old pilot bearing when we drilled it out. The hole doesn't feel smooth inside past a certain point, and when I try to put the new bearing it, it won't go in all the way even trying to tap it in with a mallet and a socket. I can feel inside there is still a little metal lip that is from the old bearing stuck on the walls of the hole, it feels almost like it is welded in there, and it doesn't go all the way around the hole. So I'm trying to figure out if I can sand it down to the point that I can get the new bearing in without hurting the shaft anymore.

The only good thing I've noted so far is the shaft still has a tight enough grip on the new bearing being about 3/4 of the way in that when I go to pull it out I have to use the bearing puller. I just don't want to mess up anymore of the good part of the shaft than I already have.

RotaryResurrection

iTrader: (8)

Well then take a fine stone or a sand roll and smooth out whatever damage has been done. Perhaps a hi res pic would help.

xblazinlv

I'll try to take a pic and post it later on.... thanks again for all the help.

xblazinlv

OK I quit.....

Who wants to donate matches and a can of gas?

Heisenberg

iTrader: (3)

yeah i ran into the same problem. I used a small slide hammer with a hook on the end of it. There probably is the outer housing of the pilot bearing left inside the shaft if the new one wont go inn.

xblazinlv

Uhhggg..... still no luck putting the new bearing in, the hole feels smooth, but I can't get the bearing to go in all the way without banging the **** out of it.

nubian

i recently put a new one in my t2, i blasted it with a torch(3-10sec bursts) to soften it, then used a scratch-all and hammer to bend it out of shape enough to grab with pliers and reef on it. worked like a charm, although lookin back it is thin enough i prolly didnt need heat. i grabbed some emery paper for a scrub before inserting the new one.

xblazinlv

I was worried about heating it up, but I might give that a try. I have a torch here, we just need to get rid of this little lip of metal and we can get it back in.

audiobot7

crazy

badddrx7

iTrader: (7)

Somethin' is gonna get fucked up...

GoodfellaFD3S

iTrader: (213)

At this point, would the Mazda Specialty Tool help? I have the mazda pilot bearing puller at the house. If you're really desperate I can ship it to ya, as long as you pay shipping both ways and a deposit on the tool .

tsmysak1

I have never tried this on a Mazda, BUT it works slick.

You take heavy grease and fill the whole cavity in behind the bearing full up. Then get a bolt that just fits the hole, or better yet, a dummy input shaft, stick in the hole and whack (tap) it with a hammer. It pops the bearing or bushing right out because the grease is way to thick to ooze past the close fit. I used to do this on small block V8's and the bushings would come right out with just a couple of taps.

Perhaps someone would see if this works on the 7??

DaveW

Now THAT'S a great idea! Hopefully he has enough of the lip left on the old bearing race to do this.