how to rebuild a 2002 7.3

[jbuller]

Ive got a 2002 7.3 f2504x4. i have decided to rebuild this enine. it has 210,000 miles on it and runs great, no knocking or anything but it smokes blue smoke like a freight trian while idleing. i replaced all 8 injectors but still smoking the same. so im thinkin rings or burnt valves not sure witch. any advice on pulling the motor like little tips on what to take off to make it easier and also once i get into it i might look for some advice on what rebuild kits to look at buying for it.

 

[RoyBoy]

Does it consume any oil?

 

[jbuller]

not that i can tell, i changed the oil in it 400 miles ago and the oil level is still the same from what i can tell. but 400 miles might not be enough to tell yet. the blow by out of the oil fill tube is not that bad i dont think, when it is idleing i can put the cap ontop of the oil fill tube and it just barley bobbles around so i dont know what the hell is the problem, the only thing that gets me is that if i drive it down the road faster than 30 mph it doesnt even smoke at all unless i realy hammer it.

 

[Crusin350]

How long have you owned the truck?
I dont know as much about these trucks as most of the people on here but I know that when its cold out mine smokes. It takes mine quite a while to warm up when it is cold and the smoke appears blue/white. the smoking when you hammer it sounds ok, mine does the same, and smokes alot more when i have the programmer turned up. Is it possable that there is an aftermarket program in the computer?
Good Luck!

 

[BJS]

I would hazard a guess to say that it's the valve seals on an exhaust valve or two. given that blowby is minimal the compression is still there not to mention that temps in the cylinder during combustion are high enough to ignite oil however the flash point of oil is not quite high enough to burn in our exhaust and the gasses cool very quickly when they leave the cylinder.

To actually answer your question it all depends on what you want to do with the engine when you're done That's the biggest question. If you're looking for a reliable DD then the answer is going to be different than I want a fire breathing, sled pulling beast.

Are you looking to do it yourself or have someone do most of the work and you provide parts and just swap engines & accessories?


Edit: just had a crazy thought could it be an oil seal failed in the turbo allowing just enough oil out to create the smoke?

 

[jbuller]

yeah i havent had the truck long only about the last 1000 miles. The reason i thought it might be compression related is because the truck is very hard to start when its below 60 degrees outside but this could be a lot of things, i checked the glow plug system and everything is fine there, i just dont know if it could be the timing off on the engine or mabey the hpop not working correctly like mabey a leak down problem or somthing.

I am planning on rebuilding it to be longlasting and reliable. i want to add the usal goodies like programmer intake and exauast but not much more than just that. I am also going to do the rebuild myself.(other than the actual machine work.) i havent ever tore into and rebuilt a deisel but have rebuilt all kinds of gasoline engines. Just dont know a good source of supply for 7.3 engine kits.

thanks agian

Jay

 

[RoyBoy]

Did you put in new glow plugs when you did the injectors? New UVC harnesses?
FWIW, I've seen 7.3's go up to 500,000 miles before needing a rebuild. My brother's old 96 is at 330k still going strong

 

[jbuller]

?

when i put in the new injectors i did replace the glow plugs also but i did not replace the UVC harness or the valve cover gasket. The only thing i can think of is that the wireing harness that plugs into the valve gover gasket on the outside of the valvecover is majorly dry rotted and i can see bare wire right there at the conection.

 

[jbuller]

what would you guys say to this i warmed the truck up and then got the tempeture gun out and read each individual tempature at the exaust port. two of the temps where a lot lower than the others so that leads me to beleive those 2 cyclinders are not fireing, any ideas what could be cousing this?

 

[DaveBen]

It sounds like one or more of the cylinders is not firing. The temp idea will tell you. The UVC harness would be responsible for the miss. Good Luck!

Dave