non cold starting 6.2

I have a m1009 that will not cold start it already has new injection pump, glow plugs,injectors , and some lines any testing procedures or ideas would be great I am thinking it is leaking down. once it is started it will restart very easily I am at a loss please help

Are the glow plugs getting juice?

yes the glow plugs have power it varies. The problem starting is when the engine has nbot run for a day even in warm weather. I believe the fuel is leaking down but I don't know how to test for where it is leaking down

If you have a visible fuel leak, especially around the fuel filter you need to take care of that first. Then if you still have a problem I would look at the glow plug system next.

On a cold engine, when you first turn the key on, check the voltage at one of the glow plugs. You should see about 12V.

There might be a simple but not commen reason behind it: The injection pump runs empty through the fuel feed. I had the same problem in 1992. The valve in the cover with the selenoids is not good, so the fuel is not keept in the pump. Refer to page 2-94 #1 check valve in TM 9-2815-237-34. This might be the problem.
Wolf

It's most likely the lift pump . The mech ones IIRC have a check valve that goes bad. I personally dislike the mech LPs anyway. I'm changing mine over to electric. This is a very common problem with 6.2 of this vintage both mil and civvy. You could try a new mech LP or put a check valve in the fuel line close to the tank somewhere.

Check the resource section, there is a document from GM talking about upgrading the valve in the IP which yours should have and also a anti drainback lift pump. If the lift pump is original I would replace it. Also carefully check the fuel filter for leaks.