Wheelbearing failure

[Kitcat]

I lost my passenger side rear wheel bearing at today's track day at Putnam Park racetrack. Car was steering itself down the straight, some times right, then violent left, all w/o any help from me(:.

 

Came in, and the wheel was very loose, too hot to touch. Pulled wheel and the hub/brake disc was very loose, I am lucky it didnt all come off.

 

Anyhow, today's technical question is, what is the replacement for the wheelbearing? Is it from a VW?

[yellowss7]

Mike, I don't know what they are from, but not too badly priced other than the hit you'll take for shipping from the UK. http://www.caterhamparts.co.uk/product.php?id_product=8

[bball7754]

Mike - At Austin the Caterham driver from Dallas (I think) also lost a rear bearing.

 

Here is post on Blatchat about rear bearing issues:

 

http://www.blatchat.com/t.asp?id=231885

 

Also, my experience buying direct from Caterham UK is that the shipping amount for small things (like two new sets of bearings) is not that bad. Can actually be similar to what you pay for freight from Denver or Mass.

 

Steve

[scannon]

Check with Caterham USA, I suspect they will likely have them in stock.

[dallasdude]

For me the rears are not so much a problem

 

I do repack the rear wheel bearings every year or two (lets say 10=15 race weekends) with Redline grease. You do have to replace the seals to do that.

 

The fronts we have to adjust a lot.....to keep the just tight enough. I think probably repack them more often than the rears. When the fronts are too loose you get pad knockback (causing a soft pedal and uneven braking) and an out of balance vibration. I let one get loose at COTA and it was pretty miserable most of the race Saturday.

[Croc]

The fronts we have to adjust a lot.....to keep the just tight enough.

 

Similar experience here. I usually replace my front bearings each year as they have had it by the end of a season even though I keep them packed with grease. Fortunately on my CSR the fronts are from a Mustang - cheap Ford parts - not used to going around corners!

 

The rear bearings have always behaved - from a 2000 VW Passat from memory.

[bsimon]

Alaskossie can fill in the details as he experienced this phenomenon on his trip from CO to AK with a brand new car.

There were a few years that the Caterham hub assembly bearing recesses were machined too deep. This preloaded the bearing excessively. The cure is getting replacement hubs from CC.

[Kitcat]

Soft pedal, uneven braking, hmm..... In addition to the car "self-steering", the right front brake kept locking up way early, and brake pedal kept getting closer to the floor (will do new brake fluid at same time that all wheel bearings are repacked).

 

What brake fluid are people using?

 

I put 16K miles on my 1st Caterham, wh/had 14K when I bought it and never touched the wheelbearings. Many, many track days as well on it. Just didnt realize this was an issue.

 

I will give Ben a call (he still has my car listed for sale on his site) and then Cat UK, if I strike out.

 

Edit: having read the links above, I mite need a new hub assembly, stub axle. Due to lack of mechanical skills I was unable to dx the extent of the damage but my amateurish dx was "what a mess". Everything was loose, grease and metal shavings everywhere. Hard to believe I didnt lose the wheel going 115mph down the straight and into a high speed right hander.

Edited July 29, 2013 by Kitcat

[dallasdude]

The knockback is generally form long sweeping corners....which flex the spindle/wheel bearings and pushes one of the brake pads back in the caliper just so slightly so in the next braking zone, it a takes a little more fluid to bring that pad in contact with the rotor.

You will notice people doing a quick double pump to bring the pad back into place before the braking zone. The later updated spindles(2003 up) are beefy enough I think the have no flex, but the wheel bearings still flex and get loose.

 

I use Motul 550 brake fluid. It has a good high temp boiling point, and a better wet point than most so it is practical for street use also.

[Croc]

The reference to pad knoock-off/knockback brings up another topic - it is amazing how many drivers these days do not do a check pump of the brake pedal (just to the point of feeling a touch of bite) before launching into a braking zone. If you go back 20 years the brakes were unreliable enough on track after a few laps in nearly all cars that I ran (due to pad knockback or fade) that it was essential to quick pump to make sure you did not have your brake pedal go to the floor just when you need it.

[Klasik-69]

Like Dallasdude, I also use Motul RBF 600 and have used it on all my track cars. It runs around $16 to $19 a pint and since it is a DOT4, you can used it for your hydraulic clutch as well.

 

Some guys use the ATE blue or gold and seem to like it too since it is cheaper. On the upper end of the price spectrum is Castrol RBF. Not sure what it's price is now but it used to be above $75/quart (ouch!) but it has the highest wet boiling point of all of them.

 

For the lightweight nature of the 7 with so little braking needed, I think most fluids will do well enough. Some tracks like Sebring with 17 turns will make it earn its price.

[Kitcat]

The suspension is apart. Wow, huge damage, the damaged spline is permanetly fused to the 1/2 shaft, hub, disc carrier all banged up, disc gouged, nuts rounded off, etc. All will be replaced.