T444E diagnostic/repair tips

[Mr P]

Post your T444E diagnostic and repair info in this topic so others might find it in their time of need.

First, the T444E is called the 7.3L in Ford trucks, much of the info for one applies to the other.

I highly recommend viewing applicable videos: Deboss Garage "everything wrong with the 7.3" is a beginner vid. Great repair info is by "Diesel Tech Ron" on YouTube. He has many very helpful vids on the 7.3 that will apply to your bus problems.

My experiences are with Fords, here are my thoughts:

1. the cam sensor can fail suddenly, it's cheap and easy to replace, keep a spare in the glovebox.
2. get a computer scanner; learn the basics (from Diesel Tech Ron vids) about which engine parameters are important and what they should read (while your engine is running correctly). Correctly interpreting scanner data leads me to a repair about 80% of the time.
3. Most engines that I work on are driven to me. Some are towed. Tow ins are because of lack of oil, cam sensor failure, or high pressure oil leaks. I've never condemned the HPOP, I've found a backed out pipe plug and bad o-rings which dump so much oil that high pressure cannot be produced.

Deboss Garage video.

Diesel Tech Ron 7.3L

 

[Dbacks2k4]

I'm personally not a fan of the 7.3, mostly dissuaded by my mechanic and a bad experience with the only one I was ever unfortunate enough to have in my fleet. It was loud and tended to spring oil leaks faster than we could fix them.

One word of caution, although the T444e is very similar to the Ford PowerStroke there are a few differences and parts aren't always interchangeable - even though they're often mislabeled with incorrect part numbers when you order online. Used to drive me crazy shopping for parts.

ServiceMaxx J1708 is free for the T444e if you have a NexIQ adapter or similar. Also allows you to modify some of the parameters like speed limters.

My only other advise is if you ever have to reseal the oil pan, the stock repair manual calls for using a liquid/gel gasket-making sealant which is very difficult to get the pan back up without making a mess or breaking the seal. There's an aftermarket gasket that can be purchased that works WAAAAY better.

 

[Mr P]

Communicating with the computer is vital for diagnostics. What is the best way to do that on a bus/T444E?

 

[ewo1]

Servicemaxx and Nexiq clone.
Mine stays in the bus while traveling....

 

[ewo1]

Link to T444e service manuals
Post #3

International Engine Manuals

I've been getting lots of requests for these and I can no longer get to them in a reasonable amount of time, so I decided to start gathering all the digital manuals I have and posting them, along with download links, in one spot. As I find more stuff, I will update each post. Enjoy! :popcorn:

www.skoolie.net

 

[nikitis]

If you ever have starting problems. I've had to use ether on mine. I tried the Silicone lubricant ewo1 above has recommended using, but my bus doesn't seem to want to start when I spray that stuff. Your bus may fair better. I do have ether with lubricant added to it however, don't buy ether without lubricant or you can damage your engine. And my T444E doesn't need much ether at all. Just a quick half second spray is all it needs and my engine will start up if it's having troubles getting goin. I never have to do it twice. I had to spray half a can of the silicone stuff. It just didn't work for me for some reason, but I would try it first for anyone elses bus because it is much safer to use if it works.

 

[Kentucky Dreaming]

If you ever have starting problems. I've had to use ether on mine. I tried the Silicon lubricant ewo1 above has recommended using, but my bus doesn't seem to want to start when I spray that stuff. Your bus may fair better. I do have ether with lubricant added to it however, don't buy ether without lubricant or you can damage your engine. And my T444E doesn't need much ether at all. Just a quick half second spray is all it needs and my engine will start up if it's having troubles getting goin. I never have to do it twice. I had to spray half a can of the silicon stuff. It just didn't work for me for some reason, but I would try it first for anyone elses bus because it is much safer to use if it works.

It is silicone!!! silicon is used in computer chips & solar panels!

 

[nikitis]

Corrected. I was speed typing on my phone and it wants to auto suggest silicon.

 

[heimlich]

My engine has a warning about spraying ether into it. Seems like it can cause it to explode from the glow plugs. Tell me more about this.

 

[Mr P]

Starting fluids of any type are a band-aid. Starting fluids can damage piston rings, making compression much lower which then mandates the use of starting fluids even in mild weather. The things that make a cold start easy are: correctly functioning glow plug system, fast cranking speed (healthy batteries and starter), and good compression.

 

[cessna175]

The 7.3/444 is a nice heavy duty engine. easy to work on , maintain ,and troubleshoot. I have one of each currently. Both run like a dream. I can't express how important it is to do regular oil changes at 5k miles if you don't want HP oil pump and injector problems though.

 

[Omnibot2000]

This was geared more to Ford HOWEVER. The base engine is the same and will give people a solid understanding of the engine operation. I included the links below as the file size was to large to attach. Can only added the smaller 99.5 update file.

https://73psd.com/94-98_73PSD_FDSF.pdf

https://73psd.com/98-99-5_73L_F-series_FDSF.pdf

The 7.3 engine and T444e is a solid engine

 

[Mr P]

Bump.

 

[Jolly Roger bus 223]

okay a squirt bottle with gas in in it is better than either and a softer start.
ALWAYS BE MINDFUL OF GLOW PLUGS?
when spraying anything flammable in.
anything diesel is addicted to starting fluid and might want it everytime.
gas is softer and i understand the wd 40 or whatever type fluid and they are better the ether but i think a sqirt bottle of gas is best?
an opinion.
was taught to me by a diesel mechanic on old school.
either turns the engines into crack heads? need to find the real issue

 

[heimlich]

Servicemaxx and Nexiq clone.

What nexiq clone do you have? I bought one and it didn't work very well.

 

[Dbacks2k4]

What nexiq clone do you have? I bought one and it didn't work very well.

I bought one off chinacardiags.com that worked ok. It's a knockoff of the NexIQ USBLINK 1. I had to set ServiceMaxx to that specific model, the auto detect didn't work like my legit NexIQ USBLINK 2.

 

[Mr P]

YouTube sources of information are also:

Powerstrokehelp

FordTechMakuloco

 

[Mr P]

Simple diesel diagnostic if a diesel cranks over at normal speed but will not "fire" or "run"....see if there is a small cloud of "raw" diesel smoke from the tailpipe when cranking. It will be white/grey in color. Such fuel indicated the injectors are putting fuel in the cylinder, but that fuel is not being ignited by the glow plug/compression, or the fuel is terrible quality. If there is NO fuel smoke, the injectors are NOT putting fuel in the cylinders which could be a lack of fuel to the pump (empty tank, bad lift pump, leaky supply line, ect.), lacking high pressure oil (low oil level, high pressure leaks, rarely a HPOP failure) or electrical issues (bad valve cover harness connections, or ECU not commanding fuel due to CKP failure).

If you own a 7.3/t444e, prepare yourself:

1. With a scanner as mentioned above
2. A familiarization with the 4 or 5 data points that are most important
3. Some of the vids from YouTube folks I've mentioned to guide you