Alloy Aluminum Rim Repair

[Don52]

The grandson of a coworker just bought a Saab car. One of the wheels leaked air. When you look at the rim you can see the story of what happened to the rim and why it leaked.

Looking at picture 1 you can see a lot of dents on the bead that would be on the side of the rim on the inside of the car. (The non-spoke side) The other rim was fine. What happened was the previous owner had a flat and then continued to drive on gravel. Most likely the tire protruded on the spoke side, which protected it.

Looking at picture 2 you can see a crack in the rim that was filled with epoxy, most likely JB Weld. What happened is that the car hit a rock or pot hole which created a flat spot on the rim and cracked it. Picture 3 & 4 shows the crack from the tire side and the non-tire side after I removed the epoxy. Picture 5 shows the flat spot on the rim.

[Don52]

Once I removed the sealant you could see that there was a lot of corrosion under the sealant. Picture 6 shows one spot of corrosion. We use a lot of salt on our roads here in Michigan, which causes corrosion on unprotected aluminum rims that causes a rim leak. The corrosion is made up of aluminum oxide, which is porous. It is much better to remove the corrosion with a flap wheel instead of covering it up with sealant. The porous corrosion can cause a leak right under the sealant. The wheel had two types of balancing weights; the ones that clip on the rim and the kind that are glued on the inside of the rim. I prefer the glued on weights because the clip on weights scratch the powder coat and create a site for corrosion to start. The fact that the clips are steel and the wheel is aluminum creates a site for galvanic corrosion due to the dissimilar metals, which further exacerbates the corrosion.

Picture 7 shows the crack opened up with a cut-off wheel. I didn’t take a picture of it but I opened up the slot to make it into a v-groove for better penetration.

Picture 8 shows the back of the weld after it was back gouged.

Picture 9 shows the weld on the tire side.

[Don52]

Picture 10 & 11 show the weld dressed up.

Picture 12 and 13 show the rim primed.

Most rims repair places will only fix cracks on the non-spoke side and will only repair one crack. I believe that the reason is that the spoke side is more rigid and it takes a lot of force to crack it. In addition because the spoke side is so rigid the weld is more likely to crack as it cools and shrinks. There might be other reasons that I haven’t thought of.

Don

[aametalmaster]

I fix them too. 99% are cracked on the backside because its the weakest. I just whiz wheel the crack completely out as in gone and fill it up with weld. A little preheat first with a torch. Then grind to suit. Now JB Weld already tried to fix it myself take a little longer because of burning out the JB crap. If its a bubbly weld I grind it and do it again until it looks good. Not only does the weld need to be good for strength it is a pressure vessel to hold air. I have been doing them for 35 years and do turn down ones with cracks on the front side or extra long cracks...Bob

[H80N]

All I can say is watch out for the liability....

Today's society is "sue happy"

Have heard some real horror stories

because of that....I have not done a rim in years

[WillieB]

All I can say is watch out for the liability....

Today's society is "sue happy"

Have heard some real horror stories

because of that....I have not done a rim in years

Only do wheelbarrow repairs. Speed is less of a concern.

[dave powelson]

Hacking cracked flat spots on AL rims

Flat spots on rims, especially if low profile tires are mounted, can suddenly
loose pressure, resulting in loss of control. Heating and beating out
a flat spot only induces more internal stress and cracking.
This flat may also affect the tire OD and flexing--transmitting a sensation
that the tire is out of round or out of balance.
A rim hit hard enough to crack with a flat spot, most likely will
be out of spec. on the below, as well.

Mfg's. have max. tolerances for roundness, face/lateral/radial runout.
A flat spotted rim will exceed one or more of those requirements.
Obviously the OP didn't/couldn't check any of the above; and
no manufacturer sends rims out with flat spots…..becuz…….

Low profile tires on rough, bumpy, pot-holed roads tear the heck out
of rims, since there's very little 'give' or resilience in that tire and the low
profile allows the road contact to severely damage the rim.

AL rim repair for low profile tire damage is a different deal than
the high profile tires. The low profile rims are often whacked, bent, runout
in several planes…and really are not repairable.
$tyle cost$ money.

The hacks that tell us all of the above--doesn't matter--are also not
aware of accidents caused by sudden deflation, since the root cause
is not normally discovered.

There's franchise shops that advertise repairing of woefully torn-up rims,
showing vid's of CNC machining new wheels, etc. I've had some not
good customer comments about the actual results from these shops
and suspect they really don't and can't weld/true/machine/inspect what
they claim to do, especially for the price quoted.

I guess that filler metal selection doesn't matter-either, since that's not
mentioned by the 'experts'.

[aametalmaster]

I guess that filler metal selection doesn't matter-either, since that's not
mentioned by the 'experts'.

Maybe not 'everyone" should be welding them...Bob

[shovelon]

I guess that filler metal selection doesn't matter-either, since that's not
mentioned by the 'experts'.

Yep, OP used wrong filler.

[Silverback]

Yep, OP used wrong filler.

how do you know?

[shovelon]

how do you know?

The silicon sheen is obviously is 4043.

[ryanjones2150]

Alloy Aluminum Rim Repair

So what would be a better selection for filler metal?

[shovelon]

So what would be a better selection for filler metal?

High strength filler that is not dependent on base metal dilution for it's strength. 5356 or better yet 5183. Those 2 filler alloys would induce some aging to the HAZ as well.

Crack should have been completely removed and at least as wide as the section is thick. Complete fusion and fill is essential or forget it.

[fabricator]

I never weld on rims. I get calls to repair them 1 to 3 times a week. They are heat treated alloys, I want no part of the liability.