3053a behind a Cummins B

[Bearitbilt]

Hey, I'm new, so take it easy on me. The only reason I'm posting is hopefully to help someone else out, I'm not really in need of info right now. I am a shop teacher in Lincoln, CA.

I know this has been covered in some ways, but my conversion is a little different. I am actually doing the opposite of what most Cummins conversions are. I am actually doing a SPICER conversion to my Cummins truck. This is where it gets interesting. I believe I have found a less expensive way to couple the b series to the spicer.

I am currently working with a 92 Dodge Cummins, and using a Getrag 360 factory bell. I am using a factory dodge engine plate, flywheel, and starter that came with the engine. I believe an NV4500 set up could be used in a very similar fashion. Most dodge Cummins engines already come with these on them. This is where the swap becomes more cost effective. Flywheels for dodges run $300 new, whereas SAE 2 pieces can run $750-$1000. There are also starters to source and align. This method allows everything, including the factory dodge clutch options to be used (with the exception of a required 1.5" hub in the friction disc).

Currently, I have the bell drilled and attached to the spicer. This was as simple as machining down the front bearing retainer on the 3053a to the same size as the dodge bell, slipping it over and redrilling the bell. I reinforced the area around the holes on the back of the bell with weld, and machined them flat on the inside for the bolt heads to sit flush. Tomorrow I will modify the input for length, install new input bearing and build a release fork (mostly because I lost mine). According to my measurements, I will need to trim two areas from the input, but will post the final measurements at the end of the machining process.

A few comments before I head out for the night.

1. I know the SAE 3 parts will allow more trans options, but the reason I am posting here is you guys are less likely to be changing your trans than your engine.

2. I'm pretty sure an aluminum bell WON'T suspend your transmission without cracking, so a rear crossmember or support may be needed. In my case, that is a typical auto setup, and I will design a crossmember.

3. I wish something like this was written when I started this project, so I could have finished my project more quickly.


In case someone nearby is interested, I also have the factory 3053a adapter ring (SAE3 to multi), bell, and winch (forward) PTO. If you have a home for them, Email me, we can work something out.

Bearitbilt@hotmail.com

 

[HanksDeuce]

Sounds like one heck of a project. Please make sure you take pictures along the way and post them up for us to see!

 

[Bearitbilt]

Ok, so today was mostly machine work. Here are the steps I have taken:

Step 1: Prep Bell. Cut recesses and drill holes in bell.

After turning down the retainer shoulder halfway down to make an alignment tool out of it, I used the retainer as a guide to align the two bells together and marked hole locations using a transfer punch. I then finshed cutting the shoulder of the retainer the rest of the way. New retainer diameter 4.85". The back of the bell needed reinforcement as there are cast pockets in the hole locations. I filled, milled, and re-drilled them.

 

[Bearitbilt]

Step 2: Prep the throwout bearing (TOB). The TOB retainer collar is too long to fit the menagerie and clear the clutch, so it needs cut back about 3/8" Here is how I did it. It may be easier to source something else, but I wanted to see how this would work.

Cut 3/8" off the end of the bearing retainer shaft. I used the lathe, but you can use anything as long as you deburr it.

Grind the "ears" flush on the back of the collar

Remove the throwout bearing, and chuck in the lather to cut down the housing. The shaft of the housing needs to be extended, and the same diameter as the bearing land. You will remove 3/8" of new material, creating a very long bearing land. See the next two pics.

If done correctly, the shaft will part from the rest as the cut enters the grease groove of the TOB retainer. The diameter is 2.132", and length now 0.990". You can actually see the factory shoulder next to the two chuck nicks in the above pic.

Machine the inside of the now exposed grease groove to .010" less than the shoulder diameter (2.132"). You need to go 3/8" deep, so we can interference fit the shaft into it. You are basically making it a short version of itself.

Sorry for the sideways pic. This is a pic of using the bearing retainer in the press to push the shaft into the TOB collar. The reatiner makes sure it start straight. I started by heating the collar to 300* F to expand it (its cast, that's why the interference is .010", then pressing the cold shaft into it.The part on the right (next to the bearing splitter) is the shortened TOB collar. You can also see the new shaft/shoulder in the middle, and YES it is stepped, and should be. The TOB only contacts the very bottom of the shaft. The rest has a floating bronze bushing and upper race that must be free to turn. It pressed very nicely.

I used a spring hone to make it smooth, checking the fit periodically on the front bearing retainer. The area with the interference fit was slightly tighter, but honed out in just a few seconds.

 

[Bearitbilt]

Step 3. Turn down the input shaft.

Chuck the input in the lathe and cut the spline back .625" if you don't, it will hit the flywheel. Make sure it stays the factory diameter for the pilot. The dodge factory pilot is the same size as the shaft. No need to make adjustments.

I will not be parting the tip here, but chopping it with a cutoff wheel on the trans. It will give me a chance to double check after assembly. My math says to cut a minimum of .25", up to a max of .75". I will be splitting the difference at .5"

The trans is now assembled. I will take some more pics tomorrow for....

Clutch Release Fork Day!

 

[rustystud]

 

[Lukes_deuce]

Sounds like a nice project. Are you keeping the entire set up in the Dodge? Or is this plans for something else in the future?

 

[Bearitbilt]

It's staying in the dodge. I actually had all the pieces for the conversion with SAE 3 parts, but the 159 tooth flywheel was mega bucks, so I went this route. I've been busy so the fork build will be moving to tommorow, while I wait on my new 13" clutch parts.

 

[MAZ537]

Sounds like a nice project !
Can you guys see the pictures as I cant...

 

[rustystud]

Sounds like a nice project !
Can you guys see the pictures as I cant...

I couldn't see the pictures either.

 

[gimpyrobb]

No, its asking me to log in to see them.

 

[gringeltaube]

It's been seven weeks now since the OP logged-on to the site, last time.
Let's hope he returns and takes care of those links.