Major issues with multiple trucks, Engine vibration, knocking, etc

[6 Nebraska IDIs]

This is a borderline 911 emergency here, but we have enough vehicles to get by so Im not posting it here.
As you can see from my ID name that we have 6 IDI Ford diesel trucks. 3 are 1983 6.9's and 3 are 7.3's.

First and most major issue is with my moms truck. Its a 1994 crew cab long box with the 7.3 factory turbo IDI engine (the one that all the Ford mechanics say Im insane about when I want parts for it). For about a year now its had minor engine vibration at 2000RPM until about 2400RPM, then it clears out (or its just spinning so fast you cant tell). We thought it was injector issues, so we bought a set of injectors (completely different story about the place we bought them from) and installed them. Now its almost worse than what it was before! I dont know if it could be timing causing this, doubt it, but we've thought for a while that we didnt get the timing right the last time. But we're at the point now that, if its rods or wrist pins, we dont even want to waste our time tearing into that cus it will all come back appart again. I vaguely remember when we first purchased this truck it would run nearly 13psi of boost at 2700RPM at full throttle. For over 2 years now its been running a MAX boost of 6psi. So we put a new turbo on it 4 months ago, didnt help.
Back to the vibration, it ran SO smooth when we first started it after these new injectors, then after taking it down the road and getting it good and warm, it started again, then got worse and worse! Just to put it out there, the new injectors had some OBVIOUS sillica sand in them from the shop we bought them from. This made me VERY upset, but we were stuck and had to use them. (Another note is, 7 of the injectors they sent us were clone G code injectors, restamps.) Im going to demand a 50% refund for all this crap. Cus for one we dont know for sure if I got all the sand cleaned out and this is causing us problem or if they arent built to G code specs correctly.

This engine only has 130,000 miles on it. Had 20,000 on a new short block when we bought it. After doing some research on the turbo engines, Im almost wondering if the shortblock that Ford installed was just a plain 7.3 and now we're having wrist pin issues or what.

HELP!
Help me with this one first, then I'll run my other issues by you guys.
Thanks, Sean

Also, if somone wants, it would be great if you could talk straight to me or my dad on the phone. Whatever works best. 402-540-7928

 

[69oiler]

have you done a compression test in this engine? is it an auto or a stick? (thinking DMF maybe?) if you had sand in the injectors (??? ) it's fair to say they could still be the problem.

does the vibe seem/sound like a miss, or does it sound smooth. is it hitting on all 8? you sure it's not a driveline thing? (u-joint maybe)

one thing, i was told by a IH mechanic that you want all your injectors to have the same code on them. the different letters denote opening pressures and other tolerances that when mismatched can cause issues.

i'd say timing probably isnt your problem with your vibration, timing will affect starting and power but smoothness/vibration shouldn't be affected IMO.

if it's definitly the engine the obvious culprits are injectors and injector pump. also, if you have air in the system it can make funny noises/vibes. but if you had air in the lines you'd probably have starting problems. a compression test would rule out rings or valve problems. how's the oil pressure?

 

[Mr_Roboto]

Are you having the same issues with all the trucks? I'm thinking fuel contamination, probably with gasoline.

 

[6 Nebraska IDIs]

Whats a DMF?

Dont have a tester or anyone to show me how to test it to run a comp test. My family is very mechanicly enclined, but we only know enough about diesels to keep them running.

The injectors were purchased from Deisel Care and Performance off of Ebay. They were advertised as G code injectors, with a no questions core return of the old G code injectors, but only 1 of the 8 was a genuine original G code injector. The other 7 were at one time an E code injector that they stamped over, to in tern "scratch out" the E code, and stamped their own G code on them.

This issue is not dirveline, this is most def. an engine vibration. Does it in neutral reving and driving. Has the ZF 5spd.

Pump has atleast 130,000 miles on it. Now it even lunge vibrates if you blip the throttle, and even vibrates all the way up more and more.

 

[69oiler]

DMF = dual mass flywheel

welcome to the site

 

[6 Nebraska IDIs]

THis is just the issue with my moms truck, I havent posted about the others yet.

 

[6 Nebraska IDIs]

Would the DMF affect it all the time, like even in neutral, or what?

 

[69oiler]

if you have 130000 on your IP it may be your problem. i used to run a 7.3 with a bad IP and it had a bad miss/vibe at steady throttle above 2000 rpm. also it would smoke blue/white. to drive it you had to gass it, speed up, then coast. it would not run right at all at steady speed.

i put a new reman IP on there and boy what a difference. this was an NA 7.3 but it sure woke up with the new IP. my boss (his truck) was amazed. it made it almost fun to drive (for a F450 dump with 5.13 gears)

if you have a weak IP that may very likely account for you low boost numbers as well. 12-13 is about as high as you want to go but 6 is pretty low.

 

[69oiler]

do a search on DMF and see if your symptoms match up at all. my money is on the IP since you have a vibe and low boost.

 

[69oiler]

also, you said it runs fine till it gets warm. this is another symptom of a bad IP. in extreme cases if the truck dies you can pour water over the IP and it will start. not recommended though because of the close tolerances in the IP but in an emergency it could get you home.

 

[6 Nebraska IDIs]

Ok, another thing. It does have a miss so Im feeling good about the IP theory.

But another thing, when you shut it off it has this really loud stutter/knock. Like "turn off ig., burrrrr, RRATTAATTTAT!" and the engine shakes VIOLENTLY at that ratatatat.

 

[69oiler]

the rat tat tat is the DMF. i have a 4 speed with a solid flywheel so it's not a problem for me but the 5 speed DMF can cause headaches. you can get aftermarket flywheels or look up Lucky's DMF mod

Mel help this guy out with his DMF

 

[6 Nebraska IDIs]

How do you check the DMF to find out for sure that its bad?

 

[69oiler]

i dunno that one. i think there's a certain amount of play between the 2 pieces that is allowable and when they wear out they get sloppy. there are a couple guys on there who know a lot about the DMF but they are probably enjoying there holiday and will chime in later.

 

[6 Nebraska IDIs]

just a PS to everyone. My family has been working on diesels for a very long time, were just getting old. lol
My grandpa built the very first ford diesel truck in 1969-1970 in a 1967 F250. A Ford 6000 Diesel tractor engine. Ford Motor company came out and looked at it and everything. THey told him, I swear on my life Ford motor company will never put Diesel engines in our trucks. He told them you're fools if you dont. In 1983 they did.
Just some history for ya.