Ok my 89 7.3 is now really hard to start. The IP was rebuilt 1,000 miles ago. It was getting hard to start and smoking white so I installed new injectors and return line kit. Now it is even harder to start than ever. After I replaced the injectors and return lines it took for ever to get it started. I tried like 5 times of trying to crank a few times waiting 30 min then trying again before it finally cranked. Once I got it running it ran good but smoked a lot of black smoke under heavy acceleration. Now it is really hard to start and I am wandering if I messed something up. The GP are supposively fairly new according to previous owner. Can trying to crank it over and over burn the gp up? I am going to check them with the test light tomorrow but I am nervous about having to change them after reading horror stories about the tips breaking off. If the gp are ok how can I check the controller? Also how would you know if the IP is losing its prime? Once I finally get it started it will fire right up all day until it sits overnight. Sorry for all the questions but I need to do a lot of hauling soon and I need this thing fixed. Thanks

 

How long does the wait to start light come on?
Less than 10 seconds or so says burnt glow plugs.

I have seen posts about some of the sparkplug brands of glow plugs burning out on the first glow plug cycle before.
So new glow plugs don't really mean anything if they were Champion or Autolite.

 

The light stays on probably 5 secs or so. If it is the glow plugs how easily do the tips brake off?

 

I dont think 10 seconds is a fair judgement, mine stay on for about 5 seconds as well, sometimes longer depending on cold it is. I don't think its your plugs, whats the ambient temperature where you live when you're trying to start it? My first guess when an engine isnt turning over is because theres a combustion issue. Either not enough fuel, not enough air, or vise versa. If you said its smoking alot, you could be running rich?

 

The temp here has been pretty warm (70-80 F) so I wasn't convinced its the plugs either. How can you tell if the IP is loosing its prime?

 

I forgot what it is, but you're supposed to take off the fuel line and you're supposed to get around 6psi for fuel, I think after 5 or 10 seconds of starting, you should get about a pint of fuel. Someone should clear me up on this, as I dont remember the exact amount. If you're smoking, that means too much fuel and not enough air. If I were you, turn down the fuel screw on the IP a little bit at a time and see if that does anything. Be careful tat you dont turn it down too much as you will be running the motor too lean, and could screw it up badly.

 

Sorry I just noticed something from your first post, if its smoking heavily under heavy acceleration, that's quite normal for a diesel. I think you may have an air leak. How are your fuel lines?

 

The glow plugs -wait to start light should stay on for 12-15 seconds if all the GP's are working correctly, followed by the relay clicking for "after glow" for up to 30 seconds after start up. This is due to the resistance of the glow plugs increasing as the engine warms up. Check out the other current post on glow plug testing procedure.
The lack of heat in the cyclinders is what is causing the fuel not to light off properly-won't start as well as white smoke.

Also it does sound like you may have a air leak issue. Double check that your return line caps are all seated properly, that the lines are not loading the caps in any direction, clamps are tight, etc. I have found that it never hurts to retorque the fuel filter once in a while just to be sure as well.

 

Well I checked the glow plugs tonight and sure enough 4 of the eight were not working. I pulled one of the working ones and found out that they are crappy Autolites. Now I am worried that I am going to have trouble getting the old ones out without breaking off the tips. Any advise on that? What is the easiest way to get a cylinder to TDC in case the glow plug tip breaks off? Do most burn out glow plugs break during removal?

On a side note I went to Autozone to get new glow plugs and the sales girl said "so you want some type of fuse" and this is right after she told the guy in front of me that she had no idea what he meant by rear differential. All I could think was ignorance is bliss.