Just finished installing a new front wheel bearing (left side). This is the second bearing I have put on that side of the car since I have owned it (6 years), the car is a rebuild.

I have replaced the right side once.

As usual, the installation was quick and easy, but it would be nice if I didn't keep killing them. I suspect that the problem is related to the turning circle. Turning right, the car will turn in around 26 feet (guestimate based on a lane being 8 feet wide), but left, it takes 32 feet.

When under the car, I see no bump stop or anything else to limit wheel travel. Is there something I am missing?

Does anyone else go through bearings so fast?

 

You should not be going through wheel bearings so fast.

#1 are you packing (greasing) the bearings properly?

#2 are you over tightening the nut on the spindle?

 

1. The hub comes pre-packed.
2. I torqued the nut down to 150 foot lbs.

 

You torqued the large spindle nut in the center of the front wheel bearing to 150 ft pounds? That seems high. The nut is merely tightened enough to remove the lash from the bearings then pinned. It doesn't end up being very tight.

I would still investigate the grease as well. Just because they're prepacked doesn't mean there is enough in there but I have not seen them first hand so I'm talking out my ***. When you take the worn ones apart is the grease firm or burnt? Is the spindle itself chewed up or bent? If the car were wrecked and the spindle slightly bent that wouldn't be good for them.

 

Well, I based 150 ft. lbs. on this...

https://www.rx7club.com/showthread.p...el+bearing+hub

Please remember that I am talking about a FD with a hub/bearing assembly. There is no damage to the spindle.

On the failed bearing, it appears there was at one time enough grease... a lot has been pushed out. I will post pics when I come back from the store.

 

Maybe I'm out of my mind right now but I swear the front wheel bearings of my FD are plain caged, tapered needle bearings. They're not a sealed bearing. Am I losing it???

Anyhoo sealed bearings fail prematurely most often from heat. Is the car tracked which subjects the wheel bearings to a lot of stress along with lots of brake heat?

 

Call the doctors. It is a hub, with (ball) bearings mounted, the ABS ring, and the studs all in one unit.

Maybe the 93s are different from the 94s?

I think the only stress on the bearings is what I was talking about as far as the turning circle.

 

Perhaps. I know my chassis is an early '93. I'll pull a wheel tonight and check to see if I'm looney

 

The 94 FSM says 131-173 ft-lb on the big hub nut.

It states that the hub assembly is not serviceable. I did look it up and Timken has a part number for this assembly - rather than buying from Mazda, it would be interesting if Timken stocks it and if so I would expect it to cost significantly less.

Dave

 

Yes, I bought theirs for $85. The nut cost another $6.00

 

Do you have some high offset wheels by chance???

When you say you had a rebuild...did you inspect the suspension pieces???

 

It has stock FD wheels. And although it has been rebuilt, I have had it aligned twice and I asked the mech if there were any issues. He said no.

 

it was on my FC, but when i put new bearings in the stock hub (as per mazdatrix) i had to retighten the nut a month later and it's been fine since. different animal altogether, but maybe the same concept.

another thing i found helpful is to tighten the nut to the right torque, spin the wheel, then rerighten it, repeat until nut doesn't move any more. i spin and retorque many times (10+ per wheel). i guess the bearing was seating, and yes i installed the new races correctly and didn't leave burs on the hub from tapping them out.

if i were you i would weekly jack the front wheels and see if they had any play in them. sounds like they're getting loose and destroying themselves.

as far as the mechanic goes, i've had people tell me that my bearings were fine and when i went home and checked they had very noticeable slop in them.

also, what do you use this car for? dd? auto-x?

 

Good point about needing tightening, but it is a sealed unit / non-servicable and it was tight (the nut) when I removed the hub. It had been in the car for a few years, so I doubt it loosened up somehow.

I'm thinking it might be like the EGR and the oil pressure sender - parts that are not reliable. The new one is aftermarket, so maybe that will help.

I am kind of surprised that no one has commented on the turing circle being so strange. I had assumed that mine was the only car that turned like this; but maybe it is common.

 

some thing on your suspension might be major wrong!! start checking thing, you are going wheel bearing too qucik. our RX-7 is not design like Truck need wheel bearing in every brake job

 

I'm about to replace a hub assembly myself but have a question about the ABS ring. The OEM replacement part I bought has everything on it except the ABS ring, is it possible to reuse the one from the current hub? Thank in advance.


Jason

 

Yes, but be careful. You can remove the old one with a brass punch and a hammer. Just be careful to hammer it evenly all the way around or it will break.

 

Hmmm..... so it requires a little finesse? As straight forward as it may seem I think I better have a shop do it for me this time. Maybe after watching the mechanic do it once I'll brave it the next time I need to replace one. Thanks for the reply Damon.


Jason

 

Or, you can just go buy the one with the ring already attached. Can you take the other back?

 

Yes I can always take the other one back, but the problem is locally sourcing one out with the ring. I don't get any deals through mazda and it'll take a while to get one online. Even if it was available through the dealership they'd have to ship it over from the other end of the country and that'll take a while too. Took me close to a week to get a replacement drain plug for the radiator.
A bunch of the local FD owners are flying Steve Kan up here for dyno tuning next saturday so I'm trying to get my car drivable so I can go hang out. If I had more time I would definitely find a hub with the ring on already pressed on. But I guess I'll have to "pay to play" this one time because I'm impatient. $108 for the hub assembly + $60 for shoptime = about 180 CAD$. That's roughly 155 USD.


Jason

 

Well, I definitely don't know anything about living in BC, but all of the major parts stores here had the hub w/ring. Sorry you are have a hard time getting parts.