new to the 6.9 liter

[bigtex]

What are some pro's and con's of this engine? This is the first diesel I've ever "owned". Its a 1988 f-250 w/ a 6.9. it had the 7.3 till a friend of the previous owner ran it with a bad radiator and literally seized the engine. so the 6.9 got put in its place. taking a huge chance with this truck and im not in the mood to get screwed. the rest of the truck is rock solid but i dont know enough about the 6.9 to put my mind at ease.

 

[gdhillon]

Welcome to oilburners!

pro
-fairly simple to work on
-6.9s arent so prone to caviation as 7.3s
-this forum is your best friend...maybe even your mistress, there is tons of info on here

con
-the burning desire to buy another one

check this out if you havent yet
http://www.oilburners.net/forums/forumdisplay.php?80-IDI-Tech-Articles

 

[icanfixall]

Welcome to the best forum for information on these simple engines.
Now you state that this truck has a differant engine in it because some other person siezed the 7.3. So now there is a 6.9... Not a problem because any 6.9 can replace the 7.3. All the external drilled and threaded holes are exactly the same thru the 6.9 and 7.3. Only outside differance it the 6.9 ahd 7/16 head bolts and the 7.3 has the 1/2 inch head bolts. Even the internal parts swap back and forth between engines. So please tell us what the block serial numbers are. They are located near the drivers side of the injection pump aluminum gear cover. Clean off the crude thats hiding them. The numbers will start with either 6.9 or 7.3. Thats one way to know what engine you really have.

 

[bigtex]

would if i could but im on r&r from afghanistan and i head back in a few days. my buddys storing it from me and ill have him lo0ok that up.

 

[Michael Fowler]

Again, Welcome to the best, and most informative site for these engines on the web.

While you are out of the country, you can read the tech articles, and get up to speed. Ignore most of what you hear from so-called "experts". The true experts are here. Most of the people who worked on these when they originally came out have retired taking their knowledge with them. If you read the various threads on here, you will see that people come here after listening to "experts" and then they got into trouble. This is a helpful, non-threatening group. We all want to see everyone get the best from their IDI whether it is a 7.9 or a 7.3 , naturally aspirated or turbo or even intercooled. A few people sell products--not to get rich, but to share what they have found that works best.
Ask questions, give the requested information and you will be happy.

 

[bigtex]

much thanks everybody. being a diesel mech. i know my way around the diesel engine, just not this particular block. hence the dumb questions

 

[bigtex]

the other thing im wonderin is why is is ******* out alot of white/bluish smoke when i drove it down the road for the first time. it sat for seven months before i got to it, but mite it be the motor warming up and cookin out all the moisture it acumulated over that time frame?

 

[Michael Fowler]

No dumb questions. The dumb ones are never asked......like how many people simply assume that the way to remove the IP is just remove those 2 nice big bolts on top of the gear cover. Smart people ask "What's the best way to remove the IP?"--even if it seems the answer is obvious....because the obvious isn't always the right answer.

 

[Wyreth]

the other thing im wonderin is why is is ******* out alot of white/bluish smoke when i drove it down the road for the first time. it sat for seven months before i got to it, but mite it be the motor warming up and cookin out all the moisture it acumulated over that time frame?

Welcome to OB, honestly one of the best and most pleasant forums I've ever been on. I dunno what caused it, but mine did the exact same thing on its way home. Same situation, it sat for like a year, in a barn. I got about 300 yards, then started fogging the countryside for about 4 miles, then quit. Never done it since. Does diesel go bad like petrol does? That might be the cause too.

As far as the pro's and cons. The engines run forever, they're a simple mechanical setup, they're happy to drink cocktails, and they like to be run hard. However, they don't make big power numbers... Period. I think NMB2 has the record at 300ish hp, if I remember correctly, and that's a crazy build. The injectors are sometimes hard to come by, and the stock head gaskets are prone to failure. Also, the fuel system (IP, and injectors) are good for about 125-150k, so if they're in that neighborhood, you may want to look into getting them replaced.

 

[bigtex]

kinda thought the truck sitting for 7-8 mo would be a small issue. this truck interested me soley for the fact of pure reliabilty. im took my club buddies word and bought it. i dont tow or hual anything super heavy anymore so big power is really not on my agenda

 

[Kevin 007]

The 6.9 seems to be less prone to valve guide failure due to lack of lubrication past the valve seals. (7.3's had this issue). Thats my biggest pro to the 6.9. And the seems to start easier than the 7.3, I think due to the slightly different per-chamber design.

 

[OLDBULL8]

Addressing the Blue/White smoke, It could be old fuel, leaky/stuck injectors, air intrusion or possibly some fuel in the cylinders depending on how it first started up. If it keeps blowing smoke, it could also be that the timing is retarded. If you don't know wether the coolant has/had been treated with SCA ( Special coolant additive) to prevent/retard cavitation, it would be best to change it. Fleetgard coolant comes with the additive good for 100K miles, many other coolants are the same.

 

[bigtex]

the truck also was ran outta fuel before it sat for so long. sorry i left that out

 

[hesutton]

Welcome to OB!

Thanks for your service! Becareful over there.

Enjoy the IDI when you get back. No real significant difference between the 6.9 and 7.3 and those were listed above. These IP's and injectors don't like to sit unused for long periods of time. The weird smoking is likely a reflection of the time spent in storage. Double up on some fuel lube and give it some time....... it'll likely straighten itself out.

Heath

 

[bigtex]

well while i helped pull a blown cat c7 outtava couger today and my a**napkin boss said i could pull the turbo and keep it. it looks in good shape and couldnt find any faults with it. any ideas on adapting this monster on to my truck? im all ears

bein deployed has its perks