After looking for the right truck for a while, I bought a 2001 F250 with a 7.3 and 6 speed manual transmission in March. This truck will be my weekend truck, as I have a 2016 F150 as my daily driver. I've not driven it much since I bought it, as I've been fixing a few things on it. I've been soaking up information from this site and found you guys to be a great group of guys who really like helping each other out. I've learned a lot by reading many of the posts, and you've helped me fix a few things already. I still have a few things on it left to fix, but a new problem developed this morning. I started it up this morning and was going to try to troubleshoot the AC vent problem (only blows air out of the passenger vent near the door) and I opened up the glove box and was feeling around behind it when the truck suddenly cut off. I then smelled wires burning and reached over and turned the switch off. I popped the hood and felt the alternator and it was too hot to touch. The engine had been running no more than 5 minutes before it cut off. I tried to crank the engine over and nothing happened. I got under to look at the starter, and as I was getting under and before I saw anything, I smelled the burned wire smell and it was much stronger. I found that the wire from the bottom of the starter (perhaps the bendix?) that went to one of the terminals at the top of the starter, was burned. See attached photo.

The starter was too hot to touch, even about 20-30 minutes later when I disconnected the battery wire. I was going to remove the starter then but it was too hot, and I decided to let it cool down. I got busy on another project and never got back to it today. I'm assuming the starter is toast and I'll need to replace it. Could the problem be something other than the starter? What would cause the engine to stop if it were the starter? Thanks in advance.

 

Welcome to the FTE! Also, congratulations on your ZF6 truck, I love my ZF6 truck!

If I were in your situation I would remove the starter, check the lugs and wire terminals and possibly replace the starter if it is faulty. In my opinion, you reaching up into the glove box when the truck shut off was coincidence and not related to you investigating the ventilation issue.

Your main battery cables could be corroded and have bad connections to the grounds on the block which could be causing the alternator to be stressed and overheat.

Inspect the major positive and negative connections and monitor the voltages of the batteries and alternator after the starter issue has been resolved. The starter may need to be replaced, but it might just be bad connections too.

 

Thanks Sous. I thought it was a coincidence too. Battery terminals are clean. I had planned to take the starter off one night this week after work and bench test it. Any idea why the engine would have shut off on its own?

 

Hot starter after a few minutes of running, burned wiring at starter, and stalling says to me that your starter pinion never disengaged from the flywheel. Starters don't like spinning that fast for long and the bushings in them will seize. They also make one hell of a generator and can induce too much REVERSE voltage into the system and overpower the alternator (probably why it was super hot too). My guess is the voltage dropped below 10 or so volts and the IDM quit activating the injectors.

 

CatD2... you had me at your user name.

You might add checking your fusible links at the passenger side fender relay to your repair/recovery list items. I'd be looking to see if they were bypassed or eliminated by a previous owner.

 

Great advice everyone. Cleatus - makes sense. Thanks for your thoughts on this. Y2k - I'll check that too. It was a farm truck and wasn't meticulously taken care of. Not in terrible shape but I keep finding little things that need taken care of.

 

This.
Im guessing that the starter got stuck.
Realize it is not exactly the same but had this happen on a Detroit Diesel engine that powered a 650 KVA generator at the newspaper I worked for. Starter actually caught fire , it was not pretty.

 

I pulled the starter this evening and the top bolt was loose (starter only has two mount bolts). It was not the original starter as it had a NAPA sticker on it. When I went to wipe the grease and oil off of the label to read it better, all of the writing wiped away, so now I can't read the model number or anything. I unhooked the wire from the starter to the solenoid and placed positive jumper cable on the wire going to the starter and grounded the negative cable to the starter housing and all I got was arcing, so it looks like it got so hot it shorted the cable. What recommendations do you have for a replacement starter manufacturer. I usually like Motorcraft parts but wondering if something might work as well for a little less. I already saw how the NAPA starter worked.

 

Since you already need to replace the starter, you might look into one of the starter upgrade options. I believe there is a Denso starter option, as well as the option of making a hybrid starter from a 6.7 PSD starter.

 

As Rob mentioned above, the Denso is a popular choice, at a premium cost though.

The 6.7L starter can be made to fit the 7.3L case. Check out the links below taken from the 7.3L PSD Tech Folder.

Starter

• 6.7 Starter Modification
• 6.7 Starter Installation in 7.3

This is a video of what the Denso and 6.7L sound like starting the engine.

[Url]

 

NAPA may have a decent warranty. Might get a new one for free dollars. Worth checking.

When my time comes I believe I’ll do the PowerMaster through Summit Racing. I’ve had one on the race car for years.

 

Hi all - thanks for your suggestions. After I posted this I went ahead and bit the bullet and ordered a new Motorcraft starter from Rockauto. $360 + core. Should be here tomorrow.

 

Inspect all related wires, replace any that are burnt. Monitor voltage with a plug in meter in the dash, see if the alternator survived.

Thread lock on the starter bolts.

 

Good choice!

David has some great advice for you too.

 

Good morning all. Just wanted to report out that I installed the new Motorcraft starter yesterday and everything seems to be working fine. Thanks for everyone for your help. I still have a question about the A/C vents but I'll post that in a new thread.