Here is a quick write up on how to install a 6.7 starter on a 7.3 Super Duty. There are two different types of stock starters that Ford installed on a 7.3 Super Duties. You can tell the difference by counting the number of bolts used to attach the starter to the truck. They are commonly referred to as a 2 bolt starters and 3 bolt starters. In order to pull this mod off, you will need a 2 bolt starter.

Here is a picture of the two starters side by side. On the left, is the 2 bolt 7.3 starter I removed from the truck. On the right is the 6.7 starter.



First thing you need to do is remove the two long bolts holding the starter together. Separate the starter as pictured.



Next separate the nose cones as pictured below



Next swap the nose cones!



Reverse the order and put the starters back together, install on truck and enjoy your new starter.

 

Well done sir!

Tagging @Y2KW57 for consideration adding this thread to the 7.3L PSD Tech Folder near the other 6.7L starter modification link as pictured below.




Moderator's Note: As requested, the original post (and this entire thread) has been included in the 7.3L Tech Folder, but not in the general engine category as illustrated above.

Instead, rotating electrical has been withdrawn from General Engine and General Electrical, and given it's own subcategories for easier to find access, labeled as Starter, where this thread and other starter threads can be found, and Alternator, where all alternator tech folder items have now been organized into, as these two specific components are very popular subjects of both search and replacement.

 

Ok...I’ll be the ginny pig. So what’s the advantage to the 6.7 starter?

 

​​​​​​It spins like a Denso and starts the truck much faster (then stock)! Not to mention it's a cheap upgrade if buying used vs the Denso.

Here is a good video of the 6.7 starter

https://youtu.be/EU2FHQs9F9k
https://youtu.be/q4H7oZRdKjc

 

got it...thanks

 

So... what made you TRY this?
Did you see similarities?

Or did you "wake and bake"?

 

Very good information! Something to file away for when it is needed. As far as 2 bolt and 3 bolt starters, is there a rhyme or reason to what starter might be present on a 7.3?

 

I believe the 99-00 trucks came with 3 bolt starters and 01-03 came with 2 bolts but don't quote me on that. However, from what I can tell, either starter will work on a 7.3 super duty.

 

The 6.0L guys have been installing 6.7L starters for years now.

 

Maybe a dumb question...what makes it spin faster? Is it a more powerful electric motor or different gearing? Not doubting, just terminally curious!

 

Just to bring this around and keep the circles of discussion somewhat concentric, I will link to another thread by Y2KW57 with details of starter part numbers and their applications.

Gentlemen: STARTER your engines...

Rob, the process AKCooper9 laid out for us is an alternative solution to the Denso starter or Mitsubishi. I have not heard the 6.7L starter mounted to the 7.3L in person, but have been told that it sounds a lot like the Denso. So, you can get a starter that is OEM quality and spins the 7.3L over similar to the Denso, but costs a lot less.

This is kind of like the KC turbine wheel in my mind... I sure would have liked to try it out before jumping to the T4 (Denso), but I am happy with what I have and enjoy learning about other ways to achieve success in order to share and pass along that knowledge. We have an opportunity to learn something just about every day, whether or not our minds are open to that opportunity is another subject.

Terminally curious, I like that...

 

This guy does a tear down on a 6.0, 6.4 and 6.7 starter. I have not clue if his answer is correct though.

 

I just did this also. I had the Visteon 2 hole starter in my F350 and the Mitsubishi 3 hole starter in the wife's Excursion. I bought 2 6.7L starters for $50 each with free shipping so $100 total. One starter was a 2015 with 11,000 miles on it and the other was a 2019 with 38,000 miles on it. I made the change with the lower mileage unit in my truck. I also bought a brand new Db Electric oem Visteon style unit because I needed another 2 bolt nose and it is currently in the Excursion. I can definitely tell a difference between the two and will be doing the switch for the second 6.7L unit into the Excursion shortly and keep the one in there now as a spare. You can see my thread here: https://www.ford-trucks.com/forums/1...r-rebuild.html

I did run into a scenario where the oem Visteon unit had smaller diameter bolts as compared to the 6.7L starter. However, the Db Electric unit appeared to have the larger diameter bolts. I can make a video if someone wants to here, but there are plenty on youtube I came across.

From what I understand via the research I did and also in looking inside the 6.7L starter, it's wired in parallel such that it gets 24v to the armature...which is also the case of the 6.4L starter. The 7.3L and 6.0L starters are not. Because of this it does take more power...in the beginning micro-second...to get them going, but they spin faster. I can tell this between the two new units with healthy batteries currently in both trucks now.

The F350 fires off alot faster than it was doing previously and ever has for that matter. It's been cold here in south Texas and I am about to go crank it up after sitting for several days to make a run to get some firewood...so we will see how it does as I've been having some cold start issues. I would definitely do this again and recommend to anyone else to do so as well. The 6.0L guys have FCIM issues with the additional power draw as seen from my research when they were doing the same with a 6.4L starter...the 7.3L, not so much.

 

I found and watched that same video this morning after making my last post. Very good content! It answered my questions. The electric motor used on the 6.7 is more efficient/powerful/rpm's, etc. The field coils are what appears to be parallel, but that does not create a 24 volt situation. What it does is provide more stable/equal voltage to both coils and most likely more voltage to the brushes. You are going to have voltage drop thru the field coils, so in a series situation the second coil receives less voltage than the first in the string, and even less voltage to the brushes. With the way the newer started is constructed, the coils should in theory see equal voltage, have less total voltage drop and supply more voltage to the brushes. In electric motors, more than anything else, voltage is going to determine the RPMs the motor turns, and at the end of the day the 6.7 starter turns more RPMs with the same load (when modified to fit the 7.3), leading me to think the design change allows less voltage drop before the brushes.
In smaller applications that is why lots of manufacturers are going to permanent magnet starters. You are not sucking up valuable current with the field coils, so all voltage goes directly to making things spin. I definitely like the idea of using the 6.7 starter. If nothing else, you could purchase one from your choice of parts suppliers, make the modification and run! It is an item that should be pretty much available most places you would want to go, which for our poor old 7.3's may be a diminishing quality. Even if not looking to upgrade it is great information to have in the file in case you found yourself stranded. The likelihood of finding a starter for any Ford diesel pickup produced in the last 25 years is pretty good!

 

I had a 3 bolt but put on a 2 bolt Denso. I almost returned it, the nose cones are entirely different. But it fit and it cranks.