Builds Dirty Koala Build - Cummins 6BT + NV4500 + HF2AV Swap (1 Viewer)

[Will Van]

Yes...but the cummins mechanical fan is a beast and moves a lot of air....about 8500 CFM when in full lockup...there arent any electrical fans out there that will push that much air.

Agreed. I was poking fun at Mr Cimarron for “keeping the bypass nipple” but not mentioning that he was running electric fans.

I want to run a mechanical fan, the bypass nipple, and a fan shroud.

 

[Mr Cimarron]

Agreed. I was poking fun at Mr Cimarron for “keeping the bypass nipple” but not mentioning that he was running electric fans.

I want to run a mechanical fan, the bypass nipple, and a fan shroud.

I'm still debating whether to attempt the mechanically on the 75 but odds are I will stick with electric. Either way Cummins run very cool if your cooling system is in good working order.

 

[Dirty Koala]

I'm still debating whether to attempt the mechanically on the 75 but odds are I will stick with electric. Either way Cummins run very cool if your cooling system is in good working order.

Cim do you have a link to this 75 build?

 

[Mr Cimarron]

Cim do you have a link to this 75 build?

Not much happening yet. I have lots of inventory but nothing put together. I will be moving fairly quickly in the next few weeks once I move the build in the garage.
75 Series cab on 80 series chassis with Cummins 6BT

 

[Dirty Koala]

It been awhile but I made a defrost switch into a momentary for my grid heater. Opened it up and took out the clicky part. Found the tread on the how to somewhere on here.
Glad you caught the wheel stud when you did. I had that happen before but my wheel popped off and rolled away. Damn wheel spacer resulted in a rolled Jeep in Silver City, NM.

Cim do you know what the name of that thread was...been searching to no avail.

 

[Mr Cimarron]

Cim do you know what the name of that thread was...been searching to no avail.

I can’t remember but it was obvious when I got the cover off which is the hardest part.

 

[Dirty Koala]

I will pull the switch apart next week and figure it out.

I can’t remember but it was obvious when I got the cover off which is the hardest part.

 

[Dirty Koala]

I'm in SLC and have lots of 80 parts if you need anything.

Hey Bryson, would you happen to have the pigtails for the two switches you gave me?

 

[Will Van]

To hold the power that I will be building, I ordered up a Southbend 13" single disc clutch kit that is good for 425hp and 850ft/lbs. Part number 13125-OK-HD.

The kit comes with a new flywheel to support the 13" clutch. It is my understanding that the SB clutches are rated conservatively, so even if my power levels slightly exceed those parameters, it will still hold fine.

I was on the fence whether or not to upgrade the NV4500 input to the 1.375" shaft, but since I am running 315's, with plans to go to 345's, I decided it would be worth the investment. I ordered an input shaft kit from Southbend also. Part number ISK1.375

Do you have to upgrade anything else to run the 1.375” input shaft? How do you change from 1.250” to a larger 1.375”? Does the ISK1.375 kit come with everything you need?

 

[Dirty Koala]

Do you have to upgrade anything else to run the 1.375” input shaft? How do you change from 1.250” to a larger 1.375”? Does the ISK1.375 kit come with everything you need?

The larger diameter input shaft requires the larger clutch/flywheel. I bought my clutch, flywheel and input shaft from southbend.

 

[Dirty Koala]

Knocked off a couple of wiring projects this evening that I had put off for way too long.

1. I figured that since I now have two large group 31 batteries wired in parallel for starting duties, just like Cummins intended, that I could combine both the starter motor and fuel shutoff solenoid plunger into one relay...that worked, so no more push button for the FSOS.
2. I wired up one of the two grid heaters using a rear defogger switch. I modified the defogger switch so it is now a momentary switch and the light comes on when you hold the button in. Wiring up the 2nd grid heater is just a few more wires all under the hood.

 

[Dirty Koala]

 

[Will Van]

Last night I buttoned up the trans (PTO covers, bellhousing and trans fluid) I used 5 quarts rather than the standard 4 as it has been said there are benefits to adding an extra quart, plus I have a small amount of additional volume now with the space in the adapter plate.

I have a spare HF2AV that I bolted up, it all went together rather easily, this was a major relief as I have the original prototype adapter from Diesel Adapter and haven't seen any details of swaps using this setup yet. I can now confirm that the cut down 2wd mainshaft and adapter plate work as designed.

Dumb question about the NV4500, adapter plate, and machined 2WD mainshaft. I know there was some drama on previous design versions of the adapter plate where all of the fluid would drain out of the NV4500 transmission and into the transfer case. How does this adapter plate work? You use the Dodge seal at the 4WD extension housing, and a Toyota seal at the adapter plate? And the Toyota seal on the adapter plate seals to the 2WD main shaft?

I guess I'm having trouble visualizing what-seals-what from the NV4500 4WD extension housing, adapter plate, and transfer case, and I was hoping you could shed some light on it. Thanks!

Edit: I guess my questions is, where does the transfer case input seal mate to on the Toyota transfer case? The shoulder of the HF2AV input gear?

 

[Dirty Koala]

Dumb question about the NV4500, adapter plate, and machined 2WD mainshaft. I know there was some drama on previous design versions of the adapter plate where all of the fluid would drain out of the NV4500 transmission and into the transfer case. How does this adapter plate work? You use the Dodge seal at the 4WD extension housing, and a Toyota seal at the adapter plate? And the Toyota seal on the adapter plate seals to the 2WD main shaft?

I guess I'm having trouble visualizing what-seals-what from the NV4500 4WD extension housing, adapter plate, and transfer case, and I was hoping you could shed some light on it. Thanks!

Edit: I guess my questions is, where does the transfer case input seal mate to on the Toyota transfer case? The shoulder of the HF2AV input gear?

That seal you circled is the exact same part number as the xfer case input shaft seal in the transfer case. So you have 2 of the same seal, 1 in the transfer case to keep fluid in the xfer case and then one in the adapter plate in the opposite orientation to keep fluid in the transmission.

 

[Will Van]

That seal you circled is the exact same part number as the xfer case input shaft seal in the transfer case. So you have 2 of the same seal, 1 in the transfer case to keep fluid in the xfer case and then one in the adapter plate in the opposite orientation to keep fluid in the transmission.

Awesome, thank you. And the adapter plate seal rides on the input gear of the transfer case? Or on the output shaft of the NV4500?

 

[Dirty Koala]

Awesome, thank you. And the adapter plate seal rides on the input gear of the transfer case? Or on the output shaft of the NV4500?

Post 380 you can see pics of how it all looks bolted together. The seal in the adapter plate runs on the output shaft of the NV4500.

 

[Will Van]

Post 380 you can see pics of how it all looks bolted together. The seal in the adapter plate runs on the output shaft of the NV4500.

Does the seal ride on the splines of the NV4500 output shaft? Or is the NV4500 output shaft machined smooth at the seal?

I guess what I'm asking is, how do you keep trans fluid from leaking past the splines on the output shaft?

 

[Dirty Koala]

Does the seal ride on the splines of the NV4500 output shaft? Or is the NV4500 output shaft machined smooth at the seal?

I guess what I'm asking is, how do you keep trans fluid from leaking past the splines on the output shaft?

its on the smooth part

 

[Mr Cimarron]

Today I wanted to tackle my steering box and PS pump clearance issues, so I got busy making a couple of spacers. I made a 3/8" spacer to move the steering box outboard and a 1/4" spacer for the drivers side motor mount.

In preparation for making the steering box spacer I picked up some M12 Grade 10.9 110mm bolts, 10mm longer than the stock 100mm bolts.

View attachment 1247124
This motor mount spacer lifts the motor .25" up, creating the needed clearance for the PS hose.
View attachment 1247125
I went down to my localish hydraulic shop to get 2 PS hoses made up. I ended up using 4000psi high temp (300 degrees) hose.
After putting both spacers in my clearance issues are all fixed.
View attachment 1247126
View attachment 1247127

Do you remember what AN fittings you used on each end from pump to steering box? I’m about to copy your setup.

 

[maxamillion2345]

Do you remember what AN fittings you used on each end from pump to steering box? I’m about to copy your setup.

Can't remember which went on the pump and which went on the box but I'm running just the stock cummins pump and 80 series box.

-6 x 16-1.5mm Inverted Flare AN fitting, Metric
-6 x 16-1.5mm AN to bump tube fitting with O Ring

As for hoses. I build a lot of hoses at work for forklifts so I used some eaton -6 JIC fittings and hose, it's just -6 hydraulic hose but not sure on the pressure ratings. I'd have to look at the hoses. I'd say somewhere around 3k psi should do you well. Any hydraulic shop should be able to build you some. Tell them it's for a forklift?

I also came out of the back of the box with the fitting and used a 90* -6 JIC female male adapter, so I could just loop the hose up and over to the box.