diesel didnt shut off. ran full throttle
 

hey guys i know this isnt the right place but someone should know and you probably want to hear this story. so i got a 84 ford 6.9 f250 for CHEAP and it ran perfect. so i replaced the batts alternator clutch slave oil and a couple other things. ive been working on it for a couple weeks and was planing on driving it 2day 2 school. well about a week ago i took the injection pump cover off to get some more smoke :metal: and the triangular cover off. well the screw wouldnt turn so i was like whatever ill just put it back on. i broke on of the screws so i jimmy rigged it and it looked like it would work. i went to start it and it started right up and ran FULL THROTTLE!!! i turned off the key, unhooked the batts, unpluged the wires on the injector pump, moved the throttle linkege and it was fine and switched to the empty fuel tank. it ran for about a min with a little diesel leaking onto the engine fron the pump then it blew. oops! thinking back i had the air cleaner off so i could have put something over the intake and flooded it but i didnt even think of it. what im wondering is what happened couse i pulled the injector cover off and it looked fine and the wires were unhooked so how was it getting fuel?

Re: diesel didnt shut off. ran full throttle
 

Not sure if you have a turbo charged diesel?

If your turbo seals are toast it will feed the engine "oil" which it will actually run on for a little bit and cause the run away symptoms you are talking about. If you do have a turbo equipped truck check for play in the turbo impeller shaft, and if there is any oil in your intercooler hoses.

Diesels have no spark, so they will run on oil, so check to see (if you don't have a turbo truck) if there is oil getting into the intake somehow. Leaky injectors will also over fuel an engine.

Beyond that, I don't know much about the old 6.9 diesels, I can tell you anything you need to know about the 7.3, 6.0 and 6.4 though :lol:

Re: diesel didnt shut off. ran full throttle
 

If you knew it wasn't the right place... then why ...
nevermind. I'll just move it to the correct forum.

Re: diesel didnt shut off. ran full throttle
 

this reminds me of a line I heard years ago.
Powerstrokes are a very efficient engine. they do a wonderful job of converting diesel fuel into noise and smoke. LOL

Re: diesel didnt shut off. ran full throttle
 

No turbos on 6.9s. Not factory anyway.

The fuel could be spraying up and into the throttle body. The fuel solenoid only stops the fuel from reaching the injectors. If fuel goes down the throttle body, it can still start and run. I have done it many times when I have fail-to-start.

Put the air filter and lid back on and try it again. If the engine still starts and runs, your fuel solenoid is stuck open.

If your 250 a 4X4? Mine is an 86. Rusty and trusty! No exhaust (well at least it is not ON the truck yet ;)), so I make bit of noise when at 2500 rpm. :metal: At low rpm, it is mild as a kitten.

You do know not to use ether right? Ether will take out you glow plugs. Use WD40.

PM me if you want. I'll help all I can.

68C15 -- Not a stroke. It's a binder.

Re: diesel didnt shut off. ran full throttle
 

Injector pumps are a bit more complex than you thought I'm betting.

I have been around a bunch of diesels for a long while and I still will not pull the cover off one. I will pull it off and let the pros do it.Mistakes are costly with them.

I am sorry that it blew.

Clearances inside those pumps are measured in thousandths of inches

Anything tweaked or "Jimmy rigged" is bad

Re: diesel didnt shut off. ran full throttle
 

hey guys thanks for getting back to me. and longhorn man thanks for moving this to the right place. so i called around and the only 6.9 i could find is at the junk yard and he wants $1000. ya right! but he will trade me straight up my 6.9 for his 460 but i gota get it running and pull it. what will that take and how hard is it. thanks

Re: diesel didnt shut off. ran full throttle
 

it's gonna be expensive to convert. new engine and all accessories, new fuel tank, fuel lines, fuel guage, tach, on and on....

Re: diesel didnt shut off. ran full throttle
 

could you give me an estimate? and the 460 is out of a 72? LTD. what motor would you guys recomend putting in there. i got about a 30 mile round trip to school but if that 460 is pre 73 than it has like 365hp and that would be badass. also what would i need to do to get it to run as in flywheel, manifolds, gas lines, ect. and i just got 2 new 850cca batts what should i do with them? will they work with the 460 and will i need 2 batts like with the 6.9?

Re: diesel didnt shut off. ran full throttle
 

You do not need new fuel tanks. Just clean out the diesel fuel. Fuel gauge will be OK too. It is a float and does not care what it floats on.

Do you have a tach now? If not, no problem, you do not really need it. If you MUST have a tach, and cannot bear to have extra lights (glow plug), get a full dash from a gas truck. Some rewiring my be needed, but that will be true no matter what.

You will need all of the accessory mounts. The actual accessories will fit the mounts. (alt, power steering, AC)

Since you have the batteries, and you have the 2-battery setup already, use it. More power for starting, longer time that you can run power with the engine off.

Remember, most of these F250 had gas engines, so all of the parts are swappable. The really hard part will be degreasing the engine bay. The 6.9s marked their territory well.

All that aside, have you looked for a 7.3IDI? It is everything a 6.9 is only better.

Re: diesel didnt shut off. ran full throttle
 

Saw this post and recalled one from my Ford work site a while back-it's pretty good...

Posted on June 16 by Greg Holekamp: A diesel runaway is when the engine rpm goes up uncontrolled and there is no way the engine can stop itself. Diesel engines don't actually require any controls on then to run. All they need is fuel and air. Gas engines need a spark at just the right time, and a fuel pulse of just the right duration to run. Also, diesels can run on a wide range of fuel. Remember when all of us diesel guys were complaining about leaking injectors on 03's that were filling the crankcase with fuel? Well, 30+ quarts of a fuel/oil mix in the crankcase will submerge the crank. One of the last steps on the diesel diag sheet is an oil aeration test where you have to run the engine at wot (3500 or so rpm) for 3 minutes and then view the oil condition. That crank whipping up the fuel/oil will make a foam that rises through the engine, and eventually starts getting drafted into the intake stream. If there is enough coming into the intake, the engine rpm will start to rise even higher. Of course, this causes the oil to whip more, which makes it rise faster in the engine - a vicious cycle. You cut the key off, but the engine doesn't care - it's getting it's own fuel from another source. Smoke starts to pour from the tailpipe, and the truck starts to vibrate. At about 6000 rpm the ground starts to shake throughout the shop and the sales department looks outside to see if a thunderstorm is coming. 7500 rpm has the shop evacuating - by this time, the whole shop is flooded with smoke. 9000 rpm brings ominous noises from the shop - a cyclic wave of sound that feels like an invisible hand pressing on your chest. Somewhere about 10,000 rpm and the engine gives up. A sound that is a combination of a nearby lightning strike and every toolbox in the shop turning over at once explodes from the shop. The sound echos and continues for several seconds. You can actually feel a shockwave disperse through the concrete you're standing on. And then, the deafening silence. You try to see through the smoke and locate the truck - but something is wrong. It is sitting at an angle, tilted down in the front. And then you see why - both front tires are blown out. There is a scattering of parts 3 bays in each direction. A puddle of fluid is rapidly spreading from under the shredded front cap. The hood and fenders are destroyed, but ironically, the grille and headlights are still intact. And your first thought is - at least I don't have to work on this one anymore! And that, my friend Bernie, is a diesel runaway.

Re: diesel didnt shut off. ran full throttle
 

Sounds like a bad day for an oil burner.

Re: diesel didnt shut off. ran full throttle
 

doby454 well i guess i was lucky! i would guess that it got to about 7000 but im not sure. well i got a couple of choices right now i could get another 6.9 out of a junkyard for 1000. a 460 from the same junkyard for 400 but he will trade me it for my diesel motor. or the neighbor has a 351. idk what he wants to do with it though. so what do you guys think? also the junkyard guy said my injector pump was worth 500 bucks. is he right on this and should i try to sell the pump?

Re: diesel didnt shut off. ran full throttle
 

well this is my first and last diesel!

Re: diesel didnt shut off. ran full throttle
 

well im back with more questions. so i found a 7.3 with a ton of miles on it for free but theres a rod nocking. can i steal a rod from my 6.9 to put into the 7.3 or will there be problems with that. the 7.3 was rebuilt at one point along time ago.

Re: diesel didnt shut off. ran full throttle
 

Not sure about rod fitment,between the 6.9 and 7.3. with the 7.3 knocking why not just get the running 6.9 for 1000 and be done with it. if you get any of the other motors your gunna have ALOT of time invested swapping it over. the knocking 73 is gunna cost more than a grand to get back to normal. because chances are the crank is gunna need turned polished or replaced. I can't count how many times i've heard of people just replacing a rod, or just replacing bearings to fix a knock, only to have to pull the motor again to fix the same problem. So save yourself alot of time and money by replacing what you have.
Now on a more up beat, if you can find a non turbo 7.3, that I'm 99% sure that is a direct bolt in.
Thats my .02 cents.

Re: diesel didnt shut off. ran full throttle
 

thanks barry, although you could have gave me more than 2 cents to pay for the motor:lol: i would like to just rebuild the motor but i dont want to put much money into this truck. it kinda a beater and the injectors are starting to go. im thinking about selling the truck for parts and getting a gas. but then again the 20-25 mpg of the diesel would be nice. ill go look at the 7.3 today and see what its like.

Re: diesel didnt shut off. ran full throttle
 

Re: diesel didnt shut off. ran full throttle
 

Uh, stuffing a big ol' rag down the throttle body? Sure it might still be getting fuel, but it does need air too....