Triumph Repair: Suspension Noise TR7, wheel bearings, triumph stag

Question
QUESTION: Dear Howard:

Thanks again for all your previous advice on my TR7 and my recent question about a Triumph Stag.

I have a question about a potential suspension noise in my 1979 TR7.  Today I got the car up and running after some long repairs on several systems.  While driving, I noticed a "whump-whump-whump" noise on turning.  I'm not sure but I think this noise is coming from the left front.  I does not appear to occur when I am driving the car straight...only on turns.

Could you possible give me any advice on how to approach and diagnose this issue?  

Thanks,
Matt M.

ANSWER: Hi Matt,

The TR-7 uses a strut for the shock and suspension. They use a lower arm but no upper arm. So any noise either has to come form the wheel of that strut assembly.

Most likely there is too much free play in the wheel bearings on the left front wheel so I would check that first and remove the wheel and look for signs that the tire has been rubbing on anything. To check the wheel bearings just jack the car up and grab the top and bottom of the tire and wiggle the wheel to see how much free play there is in the wheel. then hand spin the wheel to see if you can hear any noise from the bearings.

Howard

---------- FOLLOW-UP ----------

QUESTION: Hi Howard;

Thanks for your quick response.

I checked the car today.  I did as you suggested and I cannot find any rubbing on the tires.  When I check the wheel bearings as you suggest, I get some free play on both sides.  There is more free play on the driver's side wheel than the passenger's side wheel.  The free play is enough that you hear a light "banging" noise when the tire is pulled (held at the 12:00 and 6:00 positions).  The bearings don't appear to be making any noise.

Should there be this much free play in the bearings?  How are these adjusted?  I have read the write up in the Bentley Manual, but I was wondering how you accomplished it in your experience.

Thanks again,
Matt M.

Answer
Hi Matt,

That is too much free play you need to remove the wheel and hub and clean the bearings and repack them with grease and readjust them. If you have not adjusted wheel bearings before you can snug up the axle nut until you take all of the free play out of the bearings and note a very slight drag on the rotation of the wheel and back off the axle nut about 1/8 of a turn and check for any free play by pulling and pushing on the top of the wheel. If you feel no free play and the wheel rotates freely put the pin in to lock the nut in place. If you feel some free play turn the axle nut in about 1/16 of a turn and check it again. If you still feel free play you need to remove the hub and bearings again and feel the axle shaft for any signs that the inner bearing races have been spinning on the axle. If you find that you need to replace the axle assembly to correct it.

Howard