Oh dear....Renegadenemo wrote: ↑Thu Jun 28, 2018 12:02 amFirst engine start since 2016 tonight and, like everything else, full of legacy-headaches from 1966. Despite our best care and efforts we had a rather hot-start with much fire requiring extra effort to blow the fire out, rein in the JPT then shut down and dry-crank to get the heat out of the engine. Not a conspicuous success.
The main issues were de-inhibiting the engine, as it doesn't like to burn a mix of Aeroshell 1 and kero, possible mis-adjustment of the control runs such that we didn't achieve idle, and therefore sufficient mass airflow to pull the heat away in the prescribed startup time and the shocking design of the combustor drain tank such that its pipework is higher than the tank so it doesn't actually drain. Whose stupid idea was that? At least the inhibitor is out of there now having achieved a successful acceleration to idle - eventually.
We also remain unsure on the possible influence of our second LP boost pump on fuel scheduling on startup but at least we can simply disable that.
What was an amazing success and a great team effort was getting the boat out of the workshop with inches to spare, into the yard then back again. OK - so it took a little fiddling about as it was our first try but we did it with no damage except a few frayed tempers and a late finish.
Someone remind me why we do this?

A way to 'de-inhibit' is to do some wet motors (or cranks) - like a start, so fuel on, but with no ignition. BUT this assumes your drains work well...! ANd you need a least 1 dry motor (or crank) - so just starter only - to 'blow' any fuel left in the engine out of the back. If in doubt, do 2 or more. All of which hammers your Start system - which you don't want to really do. Bugger....

Cannot see how the 2nd Boost Pump/Tank can affect starting - BUT its a HydroMech system, so anything's possible....

Why...? Because the end result is worth it.