bean66

Hi Jmann
thanks for the brass strip idea, I'll give that a try. I've got a pair of the new machined caps on order from Mazda Motorsport so hoping the ship those soon.

thank

Junkwhale

Can't see it mentioned anywhere else, but looks like v8r have made their own tapered roller bearing hubs:

unk577

They're coming

fmcokc

Hub Update:

2 weeks ago installed new bearings and seal packed with Mobil 1 460 monolith grease as recommended by the manufacturer. Adjusted as per instructed. Drove around a bit and checked for play. None found.

Ran a race day at Hallett (CCW) consisting of 2 practice sessions, 1 qualifying session, 1 6 lap race an 1 12 lap race. The 2 practice sessions were dry and the rest were wet.

After the 1st practice session, adjusted the drivers front about 1 mark. no play detected in the passenger front and it felt good. Checked for play after each session. Both sides felt good with no play.

This last weekend raced at Barber (CW) in a 9 hour and 7 hour endurance race. Ran most of the day on Saturday ~8 hours but had an issue near the end with an unrelated mechanical. Came in and checked hubs and they felt fine but the car was hot off the track. Went ahead and prepped brakes for the next day.

Started the race Sunday morning and on the pace lap felt the slightest of buzz coming from the left front hub. Ran it for a couple of laps to confirm that it was in fact the hub. Had to bring the car in and swap out the hub. 28 minutes in the pits Grrrrr.

Here is my question to the rest of you running these hubs, Are you supposed to disassemble the hubs after each session and reset them to zero play after each session or just check to see if they have any play?

jmann

Tapered roller brgs should have a little play, don't keep adjusting it out. Pack your brgs, smear some grease on the races and add a little around the spindle in between. Adjust just to where the slack is gone then go 1 line tighter. Run the car and you should have a few thousands of play, leave alone as tapered rollers like a little play. My Dodge diesel manual wanted .008" on the rears. I wouldn't go that much, but need say .002 to .006 roughly, just so you have some. I've been doing it this way for 40 plus years and never lost a tapered brg yet.

fmcokc

They didn't like the play the first time around and failed. So this time I adjusted them as per the instructions...and they failed. These things are different than your typical tapered roller bearings in setup and adjustment. Maybe these things are OK for sprint race guys but not the ticket for endurance races where we cannot check them every couple of hours.

Oh, not trying to sound like an *** or anything but your statement doesn't make sense to me..."Adjust just to where the slack is gone then go 1 line tighter" and "you should have a few thousands of play, leave alone as tapered rollers like a little play" don't really go together unless you are assuming that they will loosen up after you tighten them.

Thanks

jmann

The play well show up after you run them the first time.

fmcokc

Hub Update:

We think we have found the reason for the bearing failures. We have constructed what we believe might be a solution.

Tested for approx. 4 hours today. Bearings appear good. Going to clean, inspect and repack.

We have a double 8 hour race in 3 weeks so should be a good test to see if we have a solution.

jmann

Mine are doing fine. These hubs were ran in a couple of cars in the 25 hr of Thunder Hill with no issues.

fmcokc

how i.e. many hours do you have on your hubs?

what kind of racing do you compete in?

jmann

I would guess around 10 hours so far. Now that I'm 74 I do mostly track days, some open track ones where they see 40 to 50 mins. at a time, but have been racing since 16 yrs old. I mentioned Thunder Hill as one of your above post mentioned these are probably fine for track day guys, but not endurance racing, I would say 25 hrs qualifies as endurance.

fmcokc

The 25 was run in December under relatively cool conditions. We are seeing these failures in 95 degree and hotter conditions so temperature might certainly play a part in their performance and/or failure.

Also, to your point on tapered bearings liking a little play I submit the following chart showing that actually just the opposite is true, courtesy of General Bearing Corp.




[img]file:///C:\Users\CHRIS~2.FIR\AppData\Local\Temp\msohtmlcli p1\01\clip_image002.jpg[/img]

jmann

Do what you want. I have ran long races in hot weather many years with tapered roller brgs. You found one chart on the ole inter webb that states such, keep running them with no clearance and you well keep having the same issues. I well take my many years of actually doing it. It's funny that there is several hundred of these being run with no problems. I was just trying to help you but it seems you know better so have at it.

fmcokc

Oh, there are a number of folks having issues with these hubs. My guys are in Indy right now talking with them at the runoffs. It's not like we are the only ones having issues. We are just trying to find a solution.

jmann

None that know how to adjust them.

jmann

Don't need to watch the whole videos, just drag the red button towards the end where the nut is being installed.

needlerollers

Tapered roller bearing is composed of an inner ring, outer ring, and tapered rolling elements. Thanks to the geometry of their design, tapered roller bearings can withstand combined loads. The rollers are guided by contact between the large end of the roller and a rib on the inner ring. It duplicates the original part in outside dimensions and appearance, but has added the reliability of tapered roller bearings.

18psi

iTrader: (76)

O RLY?

Tell us more

bahurd

iTrader: (8)

From the SKF page;

Joe Perez

iTrader: (8)

Ban performed. Carry on.