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Sierra rear hubs Wobbly ? Am I missing a bearing ?
RogerL - 28/11/12 at 06:49 PM

Advice needed

I have a MNR VortX with Seirra rear hubs. There seems to be excessive sideways movement of the rear wheel even when on the ground. It seems kind of squirrely when driving.

I can move the edge of the wheel about 12 mm in and out by pulling on the rear wheel with my hand.

Is this normal or am I missing something in the bearing assembly ? The nut on the end flange is tight.

Any ideas would be appreciated. Near the end of a long build process. Can't wait to go faster and faster....

big_l - 28/11/12 at 06:52 PM

Is the top camber adjuster tight !!

There obviously should be no play in the bearing it's self ..

Search for Mnr sportscars on Facebook and post a pic on there

RogerL - 28/11/12 at 07:19 PM

Thanks for the reply.
All the connections between the hub carrier and the wishbones are rock solid.
All the movement is between the axle and the hub carrier.

I think I need a drawing of the hub bearing assembly.

Looks like I will have to take it apart and investigate.

macc man - 28/11/12 at 08:07 PM

Have you checked the large driveshaft nut. It should be very tight. Note one is rh thread & other is left. Could be a collapsed bearing from your description.

ElmrPhD - 7/1/13 at 10:41 PM

Hey RogerL,
Did you ever find a solution?
I'm early in my Vortx build and am wondering about details/protocol for those 2 massive nuts (no, not THOSE 2...).
Seems like they are to be torqued to some un-godly number like 250 ft-lbs or so. Did you find out?
Take care,
Steve, in the NLs

RogerL - 7/1/13 at 11:27 PM

I meant to post a reply earlier, caught up in the holidays.

The inner bearing was installed with the taper facing the wrong way so tightening the nut did not make the assembly tight.

Once I turned the inner bearing around the wheel was nice and tight. I had a 2 ft breaker bar on the nut. It did not seem to require super strength to get it tight enough to get the wheel tight.

Happiness is a tight rear end.

It drives great now. No rubbing or squirely motion. And FAST I will post a driving video soon. Next is registration to drive on the street and get a trailer to take it to the race track.

Finally done.... WOW.... Now it is worth the nights in the garage.

ElmrPhD - 7/1/13 at 11:29 PM

Congratulations!!!

Bluemoon - 8/1/13 at 11:14 AM

quote:
Originally posted by RogerL

Once I turned the inner bearing around the wheel was nice and tight. I had a 2 ft breaker bar on the nut. It did not seem to require super strength to get it tight enough to get the wheel tight.



Might be worth getting a garage to torque them up correctly? The nuts don't set the bearing preload (this is set by the dimensions of the parts I think) ... but the torque will set how tight the nuts are i.e. stopping them coming undone.

Dan

adithorp - 8/1/13 at 01:28 PM

quote:
Originally posted by Bluemoon
quote:
Originally posted by RogerL

Once I turned the inner bearing around the wheel was nice and tight. I had a 2 ft breaker bar on the nut. It did not seem to require super strength to get it tight enough to get the wheel tight.



Might be worth getting a garage to torque them up correctly? The nuts don't set the bearing preload (this is set by the dimensions of the parts I think) ... but the torque will set how tight the nuts are i.e. stopping them coming undone.

Dan


Agreed. Get it torqued up.They should be VERY tight and a 2 foot breaker bar won't do it.

RogerL - 16/1/13 at 04:20 AM

Thanks for the advice. This forum has enabled a beginning builder to have success.
A borrowed my friends big torque wrench and used a long pipe for more leverage. The trick is to keep the car from moving.
Working alone. Nobody to put their foot on the brake.
Next is getting a trailer so I can tow it for inspections to get registered in CA.
My neighbors are going to get the cops on me for driving on my street without license on the car.