All back together and running on all 6.
However as it got up to temperature it started to steam. (can't upload a video here).

It's not oil. I suppose it could be coolant but in honesty I don't know what burnt coolant smells like.
I've had the valve covers powder coated - could it be a shit finish they've applied and it's reacting badly to heat?
For info the heads have not been touched.

Edit: for clarity I've done 120k service, valve cover gaskets powder coated and refitted with new seals etc. Plenu coolant line bypass. 

 

Edited May 1, 20223 yr by Lexx

Powder coating should be more than heat resistant enough for your engine bay. They literally bake the powder on. 

 

Update to this:

I think it's a case of spilt coolant burning off where it coated the manifolds when I pulled the plenum. Car runs up to temperature and holds fine and a mooch around would suggest that the smoke is coming from around that part of the bay (hard to see really - gonna dig my endoscope out tomorrow and check again).

Now just got to rectify a really poor idle issue and find the vac like that is likely causing it. 

Edited May 2, 20223 yr by Lexx