Cracks

[Whitey]

Hi all,
just though i'd post some Pics of some fatigue cracks which started to appear after 20 or so rallies.

The top rail has cracked on the seam (as shown by the hand model :D )due to flexing caused by hits on the sumpguard over time. I discovered them when i stripped back all the paint and filler to seam weld.

The second in the webs on the control arms ears. My sump guard bracket also ties all the ears together. There was a crack on both sides.

[Whitey]

I don't know whether anyone else has had this occur. I have had the alternator mount crack and bust off two front covers. Both as a result of the sudden sideways stop after a spin. The inertia of the alternator stressing the alloy over time and evenually breaks off.

The first one was cracked for a number of events and finally gave way when i spun & got dry bogged at Natcap.

The picture was taken prior to the second one at Taree, I had a half spin on Knodingbul down. Straight away the belt started to whine due to misalignment. Fortunately it survived the two remaining stages to finish the rally.

[Damo666]

Excellent, thanks Whitey. Is the control arm 'ear' photo from the underside, looking up? (I'm just trying to visualise where it is).

Its obviously getting some seam welding - does your car have any other plating at the moment, or is it factory original?

[Whitey]

Damo.
it is looking from below at the drivers side ear. Bean from Automotive Gadgets plated the sides of the ears and seam welded the the strut towers, steering rack mounts and chassis rails. I have some photos I'll post soon.
cheers

[ernysp76]

http://www.excelrally.com.au/forum/attachment.php?attachmentid=111&stc=1&d=1187245443

These have been developed for the EVO's as the cracking they experince is almost the same.

Got a gaurd of at the moment and I reckon a similar thing could easily be made out of MS or CrMo and bolted on.

[HMCA]

The second in the webs on the control arms ears. My sump guard bracket also ties all the ears together. There was a crack on both sides.

Whitey

That looks like a warranty claim to mee. HMC can supply you with some aircraft grade pop rivets. The recall continues:rofl:

I guess it show's that the cars do need to be seam welded to start with but just the same 20 odd rallies old is not bad.

[Whitey]

Not to mention 5 years of GTP racing, and only 13,000 genuine km. Although its had about 7 engines.

No need for rivets its got Automotive gadgets quality MIG.