Just put in a 7.3 idi in my service truck, it's blowing a ton of white ish smoke. Seems to be from fuel. The truck still has a few body panels that need to be put on, lights, bumper, etc. It hasn't been driven more than a couple hundred feet since we put the donor engine in. Engine has 160k miles and wasn't blowing smoke in the vehicle we pulled it out of, and has new injectors that we tested before we put in. Will this white smoke clear up at some point? I know it's needs some exhaust with done on it, but that's beside the point.
I assume shes all warmed up? No air leaks in the fuel If it just keeps coming like that you may have a stuck injector I had one like that once it did let go and ran good they do like to smoke you out on start up though
Not warmed up at all, and there may be something to that stuck injector idea. Engine sounds great, but it has a lope that you can feel. So it feels like it is missing but doesn't sound that way.
Did you check the glow plugs on that engine? They should have come on for at least 30 seconds to a minute depending on your ambient temperature. Put your testlight ground on the hot post of a battery. Touch the pokey end to each glow plug, no light-no heat. That should straighten out a lot.
The glow plugs seem to be working, we replaced the relay and it doesn't have any hard starting issues. It's getting the power it needs. The wait to start light doesn't come on, but you can hear the plugs click on and off. Starts within a second or two.
Well, i would expect it to start in warm weather. What I'm suggesting is that one or more plugs may not be getting you the in pre-combustion chamber heat to ease the smoking. That could also contribute to the loping you described.
U said it’s a donor engine.. Was it complete or did you have to swap inj. pumps or any major components..??
Even if many glow plugs are completely gone, those will fire cleanly on all cylinders within a couple seconds. Once the working cylinders start to spin the engine, the cold cylinders will come alive immediately. Looks like bad injectors or something terrible has happened.
Possible fuel advance in that Stanadyne pump-it's not uncommon and can happen quickly-worked on too many of those 7.3's years ago.
That has a blue tint to it to me, like it's burning off oil that leaked in in while changing the engine. Or the new injector could be leaking. If it's timing like Truck Shop says, then check fuel pressure and air first, doesn't that determine timing in those pumps? not saying that's most likely, just easier than taking the pump off and sending it to Thepumpguy.
It was complete, I haven't touched the injection pump and I have rode in the vehicle that the donor engine came out of. The engine had a miss from a bad injector, but otherwise it was fine, it did not smoke like this. I took the injectors from my original engine that were new and stuck them in the donor engine. This project has sat for a little while, I started this swap at the end of February and worked on it a Saturday here and there since.
I think I will check a lot of things before I touch that injection pump, I hear timing those pumps are a blast.
Next weekend I will let it run for a little while and see if it clears up. I'm guessing an injector could be stuck, besides the smoke, it runs friggin great. Here is it starting.
Mat it to the floor & let er eat. It will clear up in no time. I had a 7.3 that did that & I would Rev tune er each morning & all was good.
What made me ask that in the 1st place was.. if it has the older style Stanadyne mechanical injection pump & u installed it, there r 2 holes the dowel pin can fit in.. 1 is oblong and the other is round.. But that doesn’t seem to be the case here.. Good luck w the project..
Just an update! It was so so stupid, loose glowplug. That was it. Runs great now, let it run for awhile, and it cleared up the smoke. I think we were tired when we were putting all the accessories on that motor. Thanks everyone for the responses.