914 Woes...

Could be your ignition switch is faulty - going straight to ground.

Hi Sean.

It has been checked. Also wiring to the ignition module connectors.

All coils (except high voltage ignition ) measured - resistance values are within range.

There are/have been two problems, I believe.

First - defective ignition modules. Okay, new Ignitech plug-and-play bought and temporarily installed.

Second - I must've created that problem myself.

An A&P (?) had told me to change all hoses, since the oil hoses were stiff.

He seemed like he knew what he was talking about.

As it looked like they were the original 16 year old ones, I had new made.

But while installing them, I must have disturbed a sensor or some such...?

I saw the Lockwood video - and I have the idea that it may not be fully applicable to my engine - being a 914.

With this type of carburetor, the TCU can control the mixture with pressure (?). And the fuel pressure regulator

controls the pressure differential between ambient air and fuel delivery.

Just starting a hopefully very interesting discussion on the 914.

Cheers

Erik

Changing oil hoses I purged the engine and system with new oil and .7 bar air pressure

to the tank as in the manual.

And I checked the valves afterwards.

Hi Eric,

Random thoughts:

You flew the aircraft and all was normal.

You wanted to fly again and the engine would not start - something has changed between the flight and the non start.

You have fuel at the carburettors - so its not a lack of fuel (you are sure its fuel, not water?)

To have combustion you must have fuel + air and an ignition source - you have checked for spark and its okay (does it occur at the correct point in the engine cycle?)

If your engine has air ( air inlet clear?), fuel, spark and compression (you said the valves were good) may be the exhaust is blocked - collapsed baffles, damaged turbo?

Sean - it seems like the start circuit in the ignition modules was faulty. There were no spark from either module, as far as I could see.

After taking the connectors apart (and back again, of course) nothing changed.

I then took them apart again and measured the resistance of all parts with pins in the connectors - all is well.

When I then stuck them together again - it started (BTW, nothing wrong with the connectors). But did not run ok.

Maybe one module had a defective start circuit - and I didn't know, as I've always started on both.

And when the second module gave up the ghost, I finally discovered it. That's my theory based on other users experience.

So I have now fitted Ignitech modules. And it still doesn't run ok.

I have started the engine with and without the air filter (which has been cleaned and has new filter oil).

Turbo feels ok. Turns well by hand with just the freedom needed. Nothing wrong with the spark plugs.

A blocked exhaust doesn't happen overnight - and I would feel it at low RPMs also.