Hey guys i havent been on in a while but ive been writing stuff down on things to watch out for with these engines. Sorry to say the results on this is not good really. First off i have been seeing alot of fuel in oil cases. The oring where the solenoid screws on the injector leaks and puts fuel in the oil. Number one this is hard on the engine and is a pain to fix since you have to take off both the valve covers. Secound is just straight up engine failures. I have changed out 5 engines in the past 6months.All witht eh same issue. A no start with no HPFP. Come to find out i have a number 8 or 6 cly messedup or piston melted. Also a complaint of the engine running once the key is shut off. I never witnessed the running once key off unitl tonight which is why im posting. I was dianosing a intermitent miss on number 8 and it would come and go and fuel knock when it happened. Well i was able to duplicate it and got in to shut the key off well the key didnt shut off. The bus ran up and up and up to a whopping 5800rpm!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! i know this was the rpm cause a snapshot of the engine rpm above waring level. Well needless to say the engine ran wide open but instead of me trying to block the intake or something and risk the motor blowing in my face i just walked away. After 2 minutes of wide open it finally shut off. With about 2 gallons of coolant blown all over the bus and fuel blown all over the place out the exhaust and such. Well needless to say it blew up. I believe a tip blew off and since it such high pressure it could keep runiing. So im guessing ill be doing yet another engine. So ill see tmrrow what international wants me to do. Most likely pull the head to see what happened but anyways i think this is all linked to the in clyinder fuel they use to heat the exhaust. i mean i know that it makes you have to to clean it ofeten but why not use a injector in the exhaust like the big maxxforce 11/13/15 and isx15 isx11.9 and ism. If you dont already know this guys get a oil sample kit they are only like 13 bucks at you local trucks dealer and if you live in pa murrysville cleveland brothers CAT does them and its quick. Also get that egr and regen crap off there to make this motor good again. I know it a good one too casue any diesel motor that can run a 6000rpm for 2 minutes is pretty goodto me.lol

 

Wow that must have been a scary few moments. Wide open at 5800rpms.

What is causing the engine to stay on and go full throttle after the key is out? Is there any definitive evidence yet?

 

Yeah it was scary since there was a brand new lonestar parked next to it with the trans out.I didnt want it to explode all over it.lol
Its the tip coming off thats the issue. Once the tip comes off there is no way to keep fuel out and at 20000psi fuel pressure it just keeps running and running and running sicne its actually mechanical force doing the work now not electronic. Just a poor designed injector and stupid regen system

 

Powerstroke, are you a mechanic at a dealer? Where is it that you had to change out 5 engines!? Man that isn't good news. I am however, having great results with my motor. I have 29K completely trouble free miles. And so far, this has been the best truck I have ever owned.

 

Yes I am. Have been for a long time now. I have seen a lot and like to update on certain thing I have seen in the engines. From cummins to powerstroke to duramaxxs. I work on it all. Through in cat detroit and anything else you can think of. If anyone ver needs advice I can give it at a dealer level. Just thorwing that out there

 

Having members like you is invaluable! I am sure I will have plenty of questions for ya at some point in the future. So, overall how do you feel about the 6.4? And do you have any thoughts on the new 6.7? I took a ride in my buddy's new 6.7 yesterday and that thing is awesome. The motor is quiet and pulls super strong. The tranny is also a key upgrade. As of right now I think Ford has done a great job!

 

Thanks im open to any and all questions and if i dont know off hand ill figure it out. Its alot of fun to me to get a good hard problem to figure out once and a while. Overallthe 6.4 seems good. Not as reliable as the 7.3 but not as bad as the 6.0. I have been getting the same issues though so hopefully they will slowly start to go away. Believe it or not out of the 200 buses with the 6.4 being 3 years in service have not had EGR cooler failure. Personallyi wouldnt own one due to the run off i just experienced but overall they are good. Now for the new 2011s. The truck is awsome. The best ford ever and is more than just a truck since has all these fancy options now. Styling is great! The engine which i did drive one i very very fast for stock. All as fast as my 7.3. Nice engine for someone who keeps it stock. I personally do not like this 6.7. The reasons are the fact its no longer charge air cooled for the turbo but now liquid cooled(blows out goes straight to the intake). SCR(select catalast reduction) is just bad news. That 25mph you get with the 6.7 is lost to the 9dollara gallon urea you have to buy for the new tank.adding a gallon or more a week will get old quick. The dpf is also bigger now too. The dual compressor turbo is also a bad idea and one of a kind. May work good for stock but over complicted and not needed. reverse flow heads exhaust manifolds in the valley spells hard times for any twin turbos in the future most likely although possible but no room. The engine looks like a mess with stuff everywhere. It also sounds similar to a triton motor and i dont like there idle sound at all. Overall i wish they woulda stuck to the 6.4. Navistar has built engines for ford for 27 years now and i think it was an unwise choice to make their own engine. Since they still have a partnership with the LCF and CF look for another navistar powered ford in 5 years or so. If your looking for a truck to keep for 5 years till the engine warrenty is over id say yeah sounds good but to keep long term no way. Now PRICE is big with me too. Just looked at a 2011 f250 ext cab xlt power locks windows alum wheels manual cloth seat had locking diff though which was cool. Looked at a 2010 dodge crew cab short bed 6.7 cummins all the same optins as the ford minus the differental lock and the dodge had steel wheels. The dodge dealer also said he would install leather seats for free and a leveling kit for my wheels and tires. ok heres the shcoker. the ford after haggle was 51000. The new dodge which was also a standard wouldnt own a auto dodge. The dodge was 33000!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Now whats up with that. I also the new dodge styling too alot. Ive always been a diehard ford guy and my dad has been too for 35 years. We both like the new dodges alot and after the price difference sorry to say im going to the dark side if i choose not to fix the 7.3.lol

 

interesting read here. My 6.4 has been good so far, every few issues, I drive mine pretty hard though so I think that helps.

 

I heard the 6.7 was built from Ford just wasn't really sure why they went away from Navistar though.
The new Dodge 6.7 a friend of mine who owns the 5.9 doesn't really like the 6.7 for the new dodge but the trucks do look nice.
Have seen pics of a few Fords with a 5.9 Cummins in them. I still like my 7.3 even if it's first gen which I still have to figure out how to get engine codes when I need to.
Would you know if it's as easy as changing computers with a 96 or 97. I'm sure they has to be more to it than that though right.

 

Ford went away from navistarfor 2 reasons. One was the excessive warrenty claims on the 6.0 and other and main reson was to gain indeoendence in the diesel pickup business. They are currently the only of the 3 making their own engine. Why doesnt your buddy like his 6.7 Yavent had too many issue with these engine yet. Just with the trucks they come in. Now you say you cant get coes out your 7.3. Well i have 4 older ones a 94,95,96,02.I use auto enginuity for diaganostics on fords. It works good on all my trucks. I have diaged a cold miss on number 3 with it. A bad HPOP. A faulty GEM module. 4 bad cam sensors. a bad idm. Im not too sure what your tring do do though. I do know the older trucks 94 95 do not seem tostore inactive codes but you can still hook up to it. Generic scanners will not work on a 7.3. get AE or a scanner from matco cornwell, ect. if ya need anymorehelp jusr let me know

 

He has the 5.9 and thinks the 6.7 is junk is all or won't hold up.
As for me wanting to read codes it's mostly so I know how to since in the 94.5-97 forum everyone reads codes to help troubleshoot. I just don't know how and didn't know what code reader to buy that would work with my truck being a 94.5. Mostly I know OBDII is used on 96 and newer but not for diesel trucks if I'm remembering right.
So the AE or Matco Cornwell are scanners I buy directly from them and not places like Advance auto or NAPA stores (no idea).

Thanks for your help.

 

The ones from matco and cornwell are expensive. AE you need a laptop computer to use which i have multiples of. The AE you can buy from www.itpdiesel.com youll need to find a local tool dealer to buy the other ones from. AE is only 350 and well worth iti have it for all makes and modles. I use it allthe time and love it. All 7.3s use obd2 also just the older ECMs where not advanced engough to hold old/inactive codes

 

Thanks again for the help!!!!!!!!!!!!

 

Your welcome. If you ever need any help diagnosing your truck just message me on here ill be able to help out no problem

 

hmmm. Im of a little differnt opinion. I personaly cant stand the 7.3. it was a good engine in its day. The 6.0 is a great engine with quarks. the 6.4 is just a mony pit that is waiting to empty your pocket.
The 6.7 Ill wait a year before I form that opinion. there are a few designs things I dont like but they may still work just fine.

Biggist failers of 6.4is caused by
failed radiators
failed t-stats
failed front covers
water in fuel. we see lots. and thats customer pay about $10k-12K of damage
max spec is 500ppm h2o in fuel sample.

o and for the op. there is a knowen with the injectors leaking at the pizostack. ford has a recall on it. there were a batch of injectors built with non fuel compatable o-rings thats why the are failing.