All
I thought I'd give you all a heads up on my position with reproduction TR4
steering racks made in Argentina and supplied by MOSS or via others.
I have had another near lethal failure this weekend on the Rally of the Tests,
costing me a high placing and a class win as well as the car or worse. People
could have been hurt very badly. This is the second time.
The issues are threefold in my experience, the first two are serious safety
matters hence my email to this group.
1. The main steel rack tube is pressed without any notching or machined
scoring into the alloy pinion housing, meaning that on left hand lock the rack
tube parts from the housing and control is lost. This is because the rack has
nothing to bear against and therefore the wheels end up pointing in opposite
directions. The alloy housing appears to be made from a material of
insufficiently high quality in my opinion and the press fit is poor.
I am aware of 7 failures now, 6 on competition cars, one of which was mine and
which I was lucky to walk away from.
2. The nut and spring on the top of the pinion housing (which allows the rack
preload / play to be adjusted) unwinds and falls off, causing loss of control
and excessive play in the rack, as well as ingress of material as it's open to
the atmosphere. This is another potentially lethal failure mode and caused
because the peening of the pinion housing / nut fails and the nut just spins
itself off. Again my opinion is that this is due to poor material, design and
manufacturing.
I am aware if two such failures now, one on my car again which we were lucky
to survive unscathed.
The cast alloy pinion housings also appear to be poorly cast, with blow holes
evident in the assembly indicating poor material, process and quality
control.
3. There is a third problem in that the threads on ends of the rack are not
cut properly, so track rod ends will not fit. Theses need to recut and again
is evidence of poor manufacturing and dimensional control.
I am working with TR Enterprises in the UK to develop a short term fix (which
we have done) and ultimately have some racks made that are fit for purpose,
however meantime my opinion is that anyone who has one of these 'Made in
Argentina' steering racks should talk to their supplier and satisfy themselves
of their safety in use.
I for one will not be using such a rack in an unmodified form and will replace
it as soon as is possible with a product that is designed to be safe in use.
Needless to say I wish to discuss this with MOSS and I am awaiting their
response.
Regards
Tony
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fot@autox.team.net
http://www.fot-racing.com
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