So I had a new experience in the shop today. I was installing some new tires on some wheels that were refinished in the past for a new customer. When I went to balance them they were needing 6+ ounces of weight on th inside of the wheel and 3+ on the outside (real bad). There was no sign of any imbalance when being spun, and I rotated the tire several times on the wheel to try and overcome any tire high weight spot. Then when I was hand spinning the tire on the balancer it sounded like there was some rocks on the wheel. I could find nothing. Then it hit me. The sound was coming from inside the wheel. These were hollow spoke wheels. Hollow spokes have a special valve stem that runs though the hollow void in the wheel. This is how they remove the sand casting when the wheel is manufactured. However, if you refinish the wheel and do NOT cover this area when sand blasting all the sand will get into the wheel. This is what happened here. When I removed the valve stem, it looked liked an hour glass of sand pouring out from inside the wheel.

So be careful and be sure to remind and shop refinishing your wheels that these are hollow spokes and that the valve stem area is to be covered when taking off the old finish........

 

Yikes, "weights" that move inside the wheel! As a new hollow spoke owner, thanks for the gouge!

 

yes thank you as well, my car goes to the paint shop this week for repair and I too am a new hollow spoke set owner looking to have mine color matched while at the paint booth. Great heads up!

 

As a follow on to Bob's advice...

If you have had your hollow spokes painted or otherwise distrubed around the valve stems (abrasive blast, sanding, etc.), also check the mating/wiping surfaces for the valve stem seals/o-rings. Grime or abrasives could lead to a slow leak.

IMHO, I would use new seals if the valve stems have been taken out...

$0.02

 

...yes, and let's not forget the dangerous issue with chromed hollowspokes!!

I consider myself very fortunate that I was able to get some trade-in credit on mine when I bought new wheels.

 

look what I just found, ----- PRINTED ----- , and faxed to my dealer.
I have 140 grams (5ounces) difference on my rear left.
They refurbished my wheels last year...
I knew there should be sand or acid inside, but never knew where it came in from....

 

So, how do you get all the stuff out? One of my wheels was blasted, I shook that thing for hours, getting about three ounces out. Sounds like there are still a few grains in there...

Thanks!

 

Vacuum it, thru the valve stem hole.

 

Probably no easy answer to getting sand out once it's in other than shaking and turning, shaking and turning and then shaking and turning some more. A vacuum cleaner requires air flow and there's effectively only one access hole to a convoluted cavity. Good luck!

 

How about filling with water and having the water drain out the sand? Yes, you would need to let the wheel dry thoroughly, but at least you would be able to flow most of the sand out of the wheel.

 

NO WATER.
The material used for blasting flows easily.
Place two empty tires on top of each other, and place your wheel on top at a 45* angle the spokes
facing up. Now with a rubber hammer, tap all around while turning the wheel, WITHOUT tapping on the front
not to scratch the wheel.
Settle the wheel with the valve opening at the bottom of the wheel.
Now if you shake the wheel, the sand will go out from the valve opening, FROM THE BACK.
Do not try to let sand out from the front.
If inspected closely, you could see that the opening from the back has grooves to let anything inside to flow out.
After doing the tapping and emptying proceedure a couple of times, place the wheel on the balancing machine Without the tyre and test.
The material is heavy, so a small quantity is a lot of weight inside.
I had a difference of 5 ounces. when emptied, I had around 0.176 ounce balancing per wheel after...