1969 Elan s4 timing/starting issues

[vstibbard]

It sounds like when you adjusted the tension you wound the tensioner in too far.

The workshop manual gives a clear visual method of checking chain tension with the cam cover off.

V

[vxah]

You don’t say exactly where the cam sheared off? It’s going to be quite important to understand what caused the failure in order to prevent a repeat!
I’m guessing you didn’t build the engine so could the po have made a mistake with previous work? Camshafts have been known to break but it is unusual for a standard set up to do this, a keen eye may be needed to look over your engine?

[alan.barker]

I've heard of people breaking camshafts when tightening down camshaft caps
Alan

[rgh0]

There were 3 types of standard Lotus camshaft fitted to the elan and they can be identified from the grooves on the hub where the sprocket fits

No groove - standard "B" type cam
1 groove - SE "C" type cam
2 grooves - Sprint "D" type cam.

Replacement cams of these types can be sourced through the usual Elan parts suppliers - e.g. Dave Bean and others

[nmauduit]

I've heard of people breaking camshafts when tightening down camshaft caps
Alan

it's easy to apply a great bending leverage if the front locating flange is not properly located into the head recess and the middle caps are torqued in...

[alan.barker]

There are 4 different Camshafts. Don't forget the "E " type also plain no grooves.
Ref Miles Wilkins page 181 "Lotus Twin-Cam Engine"
Alan