A TR4a owning friend of mine told me today how his crankshaft snapped
whilst doing a steady 80 mph on his way to Coventry. This is around
3,500 rpm on a TR4a. It broke between the flywheel and the back rod.
I'm told racing TR's have a low redline of around 5,500 rpm.
Is there a cure for this or is it a design feature ?? I suggested
nitriding the crank and having it the short motor balanced as
individual parts and then as a whole from fan to clutch. Are TR lumps
prone to this problem and is it an oil feed problem or are the cranks
Any suggestions ??
My crank (ford OHV) is tuftrided and balanced and the engine red-lines
at 7,800. I use Cosworth bolts and special Vanderwell bearings, a Kent
OP5 oil pump, Valvoline 20-50 racing oil, extra sump baffling and the
oil is changed every 3,000 miles so I hope to avoid this kind of failure!
The flywheel is lightened also.
John Upham, (Chemical Physics Ph.D)
University of Sussex, Brighton, UK.
Email: email@example.com (BITnet)
Tel: +44 273 680500 (eve)
Tel: +44 273 678332 (day)
Fax: +44 273 671966
"I've counted them all out and I've counted them all back"
Murray Walker (?) commentating on the restart at F1 WC, Spa, 1990