[Fot] Failed Parts Alert

[Scott Janzen]

I’ve been using the trunnionless front suspension vertical link on my GT6 that Canley Classics sells for the past two years.  I’ve now had two fail the annual magnaflux tests.  They cracked in different locations, one right at the machining line for the flat for the stub axle nut, on the back side where the steering arm passes through, and one on the upright at what appeared to be a casting mark, near the bump you see in the photo below.  Neither crack was visible to the eye. The upright Canley sells no longer looks exactly like the photo - it now has a machined area on the back side, away from the wheel, much like stock ones.  Maybe I just had bad luck, but between two cracks and some binding issues at the ball joint I had to rectify, I would no longer recommend these.

I started using the Canley units when the stock ones developed cracks in the traditional place at the top end of the threads where the trunnion is.

I have now installed uprights I got from Jigsaw Racing https://jigsawracingservices.com - Mark Field, in England.  The main difference from stock is they are not drilled for a grease fitting or grease boring down into the trunnion, which should make them stronger where the stock ones usually fail.  Mark races Spitfires and GT6s for himself and for customers in vintage racing and claims he has never had a failure.  He further claims that the units are made in the original forging molds and by the same people that made the Stanpart units.

Main point is, even though it’s a pain, pull your critical parts off and get them magnafluxed at least once in a while.  I’ve become paranoid and this is now an annual exercise.  The machine shop I go to usually does it for free while I am watching, probably because I’m usually dropping off engine parts where the real dollars get spent!  

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