Cummins NHC 250 change out need advice

[armytruckdiesel]

ok, third attempt to post this time with a picture

I finally got back from my 1,300 mile trip of picking up the new NHC 250 from North Carolina. The old Dodge Diesel dually did just fine with the weight of the engine and container in the bed and averaged 17.6mpg for the trip. I didn't shift the load as far forward as possible due the weight of the ranch hand on the front and not having the best front tires.

We have to swap out some items since this engine is set up for the 900 series automatic trucks. It has a different center exhaust manifold angle, auto trans setup, fan height is different and a few other small items. My question is what tips do you all have when I do the engine swap if any? Are there any items that I should replace at this time such as engine mounts/etc?

How do I allign the clutch, are there any special tools I need? Any tricks??

Thanks again for all of the help,
Andy

 

[doghead]

Try resizing your pics to 640x480.

 

[armytruckdiesel]

Second attempt on pic

Hopefully this works.

 

[armytruckdiesel]

The truck is a 1977 M812 by the way

The truck is a 1977 M812 that we are swapping engines in. I'll include a picture of the truck delivery from last year since I have finally figured out how to post pictures.

 

[armytruckdiesel]

pic 2

Making the Peterbilt 379 look like an Isuzu.

 

[M1075]

RE: pic 2

That engine container looks huge in that dually! Nice looking truck by the way.

 

[steelsoldiers]

We have to swap out some items since this engine is set up for the 900 series automatic trucks. It has a different center exhaust manifold angle, auto trans setup, fan height is different and a few other small items. My question is what tips do you all have when I do the engine swap if any? Are there any items that I should replace at this time such as engine mounts/etc?

How do I allign the clutch, are there any special tools I need? Any tricks??

Thanks again for all of the help,
Andy

Hi Andy. Nice Dodge and nice M812. Sounds like a fun swap. I would say replace the pilot bearing, the throw-out bearing and clutch/pressure plate (if they are at all worn). I would have the flywheel honed. I would replace the rubber motor mount busings. It would be a good time to replace all your belts and hoses too. No since leaving anything to chance. There is a specific clutch alignment tool for the 809-series trucks. I will look it up for you when I get a chance later. The other option would be a cut-off tranny input shaft if you have a junker or an appropriately sized dowel. Do you have the 809-series manuals for your truck? I would make myself very familiar with the section on replacing the power-pack.

 

[armytruckdiesel]

thanks

Thanks for the compliments. I think the Dodge did a sigh of relief when the motor was taken out last night. The Cadillac ride is gone.....
Chris-Thank you for the advice and I look forward to hearing from you on where to purchase a clutch alignment tool. I do not have a service manual for this truck. I had one for my M35a2 I had in high school and it came in quite handy. Where is the best place/price to find a paper service manual for this truck? I'm looking forward to the swap.

Thanks again,
Andy

 

[steelsoldiers]

RE: thanks

You can download the manuals from LOGSA. I checked the manuals for you and found the following:

Clutch Alignment Kit p/n: A37M NSN: 5180-00-449-3785 Supply cat. number: 4910-95-CL-A31

You might try your local Cummins dealer for it.

 

[WillWagner]

RE: thanks

Is the trans input shaft just a normal 2 inch?

 

[armytruckdiesel]

Trans input shaft

Will,
I'm not sure what the trans input shaft size is. I'm kind of going into this project blindfolded. I'm looking into some parts manuals.
Andy

 

[jatonka]

RE: Trans input shaft

My M51A2 dump has a 1.75" input shaft. I think the 800 series does too. The alignment tools are made also by OTC. You can get them at truck shops. Also the Snap-on man or Matco tool man has them. John Tennis