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Discussion Starter #1 (Edited)
My first post here, so rather than my normal, useless blathering I will actually contribute something useful:rasta: (hey, there's a first time for everything...)

I am using a Ford/Cummins flywheel bellhousing system, to connect up to an A/A "Ranger" OD box and a Ford NP435/NP205, which was preexisting in the truck.

The Cummins bellhousing bolted up just fine. The stock 4BT starter location posed a problem, though. Typical of Ford starter locations, it was on the turbo side of the engine room...big problem. The gear-reduction design of the Denso placed the Denso motor (remember, the solenoid is located axially with the starter pinion gear, with the motor is offset to the side by a few inches...those inches were needed for the turbo down pipe.

That motor was located about the 10:00 o'clock position, leaving about an 1/8" air gap around the 3" pipe. Class, can you say, "NVH"?

The starter uses a 2-bolt design, and the "other" starter I had on hand was a three-bolt design from a '98 Dodge 6BT NV4500 plate, which I dismissed from thought 'cause it WAS a 3-bolt, NOT a 2-bolt. Big mistake. Ooops.

The Dodge starter bolts up, and places the motor portion about 2:00 o'clock...nestled in the "C" channel section of the frame rail (NOT touching, neither), and outta the downpipe's way. :beer:

The 4BT starter used a two-bolt, diametrically opposed bolt flange, their centerline crossing the centerline of the pinion gear axis. Interestingly, so did two of the three bolts on the 6BT piece; Dodge/Cummins/Denso didn't use an equadistant triangular bolt pattern with the pinion forming the triangle's center, but rather used a "T" pattern, and they just stuck the third 6BT hole out there by its lonesome, sorta like at the base of the "T". I slapped in the starter, and simply didn't use the third hole. Duh.

Both starters had 13 teeth, and the nosecones were functionally identical. The 6BT pinon gear extended .040" further outward than the 4BT, but I think we'll be OK.

Basically, I will find out this weekend if this swap actually works when I fire the mess up for the first time, but for right now I'd say that, in general, 6BT 3-bolt starters will work on Ford 4BTs...and since Chevy starters work on Fords...

Eddie
 

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Hey, now that's some great tech. No telling how many guys are saved from grief and needless expense thanks to your taking the time to explain, clearly! I hope all of your project advances just as smoothly.
 

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very cool.. Can you take some pics?
 

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Discussion Starter #4
Kids, Don't Try This At Home...Or Anywhere Else, Either

It doesn't work; Don't do this.

Yes, a 1997 Dodge 6B starter will bolt up to a Ford 4B flywheel plate just fine, and does provide a lot of room for the turbo down pipe, inches where they matter, which is a problem on all Ford swaps.

Yes, the starter snout fits correctly and the pinion gear extension is fine, as well.

Unfortunately:

The 6B's starter pinion axis is located 'bout .25" inches inward (toward the crankshaft centerline) than the 4B starter, causing the drive pinion to impact the flywheel, not the ring gear. (Sniff) Dern thing sounded like a gasser Chevy tryin' to start. (Snivel-whine-moan)

Bolting the 4B starter back in cured the problem, and it did spin the motor just fine. Now to finish the fuel lines and install the plastic tanks, and---maybe---

Side note:
I've learned ahelluva lot about starters, and taken a lot of pics; enough for a long article, probably too long to put up in a simple post, but I'd like to share what I've learned...are there any plans to begin an article section, or should I just do a series of posts?

Eddie
 
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