7.3 diesel won't start sometimes

I have a 1990 7.3L diesel that only starts sometimes. I have a brand new altinator and starter and 7 month old glow plugs. Is it a leaky system or bad pump? Once it starts it runs great and no problems. I have a battery problem also. The truck will read 12 volts on a meter but some mornings when I go to start it it will barely turn over. My radio only works sometimes and I think it is shorting out. Could that be the reason the the truck won't start? Any advice would be awesome. I'm a young owner and this is my first diesel.  

How old is the battery? Are the cables in good shape? I've chased electrical gremlins for weeks when it was just a bad ground or battery!  
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Does your truck not start when the engine is turning over?

Every time you get a no start is it because you lost electrical power?

Unscrew your fuel filter it should be full all the way to the top. If not you have a fuel leak and air is in the system.  

It will start and then die, then it takes 3 or 4 tries to start it again. It always turns over. I have never had a problem with total loss of power. My terminals on the battery are two weeks old and the batteries are 5 months old. I haven't checked my ground yet. I also have a problem with my radio cutting out on bumpy roads. Would something like that be causing the broblem with my altonater having trouble charing my batteries?  

One thing good about older diesel engines is they don't need electrical power to run once you have it started (unless you swapped your mechanical fuel pump located on the front passenger side of the engine for an electric pump). You could disconect your batteries and alternator and your IDI would still run just fine.

The radio in my Ford does the same thing. One day I was driving along and it just started working. I have to jiggle the volume button for it to play out of both speakers.

Does your volts go up when you start your engine?

I think you have a fuel problem. You might have an electrical problem too. Get an ohmeter and see if there is any resistance in your + - battery wires. If it says 0 you have a short. Disconnect both batteries first. Or just start pulling fuses one at a time and see if your drain goes away.  

Although you would need electrical power to turn the fuel switch on and off on the injection pump. I haven't looked at this switch yet.  

check your independent ground cable from the engine to cab, should be a bare flat cable if there is not one there install one. secondly check both battery cables for any cuts and is you find any abrasians check if the cable is green and coroded in that location. check your battery as well for a bad cell  

on the top of the injector pump there are 2 electrical connections. if those connections are not recieving power you cylinoid won open to let fuel in. check the contact on those.  

I had a simular problem with my '96. i had to take it to the ford dealer and it was some sencor. but it had a recall on it luckly. Maybe you should find if your trck has a recall at all  

i have a 1996 f250 7.3 and it was running fine and then once i did a tranny flush and pulled it out of the garage it died. i put a new fuel filter in it and now it wont start. if it does start its only for a second. but if u hould the pedal half way onces its running its fine. but it wont idle. what could be the problem?