7.3 l diesel wont start

C190 is a 2.0 L OHV 8V engine same as marine 4AA1.
when warm did you try diesel test fuel?
runs now , right, or runs and stalls. right?
that be the biggest clue there.
besides black smoke.
lost compression hot.
or lost fueling hot.
simple test for compression and test fuel....... leaving what?

the heading is diesel glow plug relay and then you go on about a choke and petrol inplug holes
what have you got a diesel engine or a petrol engine

Sounds like your engine might be low on compression or your glow plugs are not working very well

The Duramax fuel filter assembly is bad about sucking air. Replace the fuel filter assembly. It comes with a new fuel filter.
I need some good feedback.

Never, ever use starting fluid in your diesel.

Taken from the Owners Manual - Diesel Supplement:

Do not crank the engine for more than 30 seconds at a time as starter
damage may occur. If the engine fails to start, turn the key to OFF and
wait 30 seconds before trying again.
Do not use starting fluid such as ether in the air intake system (see Air
Cleaner Decal). Such fluid could cause immediate explosive damage to
the engine and possible personal injury.
Do not add gasoline, gasohol or alcohol to diesel fuel. This practice
creates a serious fire hazard and causes engine performance problems.
1. Make sure all vehicle occupants have buckled their safety belts. For
more information on safety belts and their proper usage, refer to Seating
and safety restraints chapter in the owner guide.

The fuel filter may have got to the end of it's life and will need to be replace. Start with the simple and replace the fuel filter. The filter should be replaced 15,000 mile or once a year to ensure that the fuel system is running 100%. Good luck and keep me posted.

It sounds like you aren't getting fuel out of the cold start injector... remove the injector when engine is cold and switch on ignition... you should get a fine spray pattern for a few seconds... if not then there is probably a problem with the cold start circuit (Temp sensor fault), or the injector is faulty. pull electrical connectors one at a time and look for corrosion... Hope this helps...;-)

sounds like timing cover or water pump

I had same problem. Engine will start if you crank it for awhile. This is because the fuel pump has a . check valve that is supposed to keep fuel from running back into tank and hold fuel at pressure so it will start immediately. If valve leaks it takes awhile for fuel to be pumped back up to injectors. Replacing fuel pump fixed my problem.

cant start deisel 3.0 lilter sounds like there is no fuel getting to the engine