1975 Dodge Crew Cab Power Wagon Build and Cummins 6BT Conversion

[Dustoff35]

Disassembly of the chassis continues with removal of the Getrag 360 5-speed transmission. Apparently, some mice took up residence inside the bellhousing while the chassis was parked in the field. They scampered off to a corner of the shop once the transmission was set onto the floor.

[Dustoff35]

This what the transmission looks like inside. Apparently the shifter seal failed and allowed some rain water to seep in, there is some corrosion on top of the gearset and inside the top cover. Fortunately, it is not seized. There is still movement of the gears and shifter. No doubt it will require a rebuild. We will spray the inside with Kroil and set it aside for now.

[Dustoff35]

Back to the NP205 transfer case. Once the housing was clean and dry, we masked off all mating surfaces, primed and painted with duplicolor engine enamel in a cast-iron color.

[Dustoff35]

Here are most of the additional parts as they are restored by electrolytic rust removal, abrasive or bead blasting and then primed and painted. I also use Evaporust on a lot of the bolts and small hardware and brackets.

[Flyin6]

That came out nice

[Dustoff35]

That came out nice

But wait, there’s more…

[cj7ox]

Looking good! 

[JR]

The grey looks better than the black I did mine in before.

[Dustoff35]

Here is the final layout prior to assembly. I obtained a NP205 full rebuild kit from Randy’s Worldwide with all bearings, seals and gaskets needed. I also purchased the technical manual from Torque King.

[Dustoff35]

We pressed new races/bearings into the idler gearset and reinstalled into the housing. Once installed, we checked endplay with a dial indicator.

[Dustoff35]

We just continued the assembly, the Torque-King manual has step-by-step instructions and covers all the variants from different automakers and model years. The rebuild kit from Randy’s Worldwide contains all the parts necessary. It is a complete kit.

[stlaser]

Looking good

[Bigdave_185]

This is a fun one to watch. Looks like all new things


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[Dustoff35]

Thanks.

Pressing the double seals into the input housing.

[Dustoff35]

This part was fun. 15 roller bearings inside of this shaft; we used petroleum jelly to hold the bearings in place as we installed them and 12 gauge wire to hold the spring retainer up while we installed each individual bearing.

[Dustoff35]

Here is the completed NP205. I tried to post up a short 10 second video but it didn’t seem to work…

[Flyin6]

I hope that doesn't rust!

They look so good when they are first built.

I vividly recall packing those 15 roller pins inside the access as you did. I recall using assembly grease to hold mine in there.

[Dustoff35]

The cast-iron case is primed and painted, as are all other cast and steel parts. I used paints from duplicolor and Eastwood that look like cast iron, bare steel, aluminum, etc. I clearcoated most of the bare aluminum. The plan is for this truck NOT to see any salt and minimal rain. I did come across a black-oxide process for a lot of the OEM hardware that we are re-using. Degrease, De-rust, bead-blast and then oxide. I will outline the process in a future post.

[Flyin6]

Very nice!

[JR]

I like the grey over when I did mine. It was black with stainless hardware.

[Dustoff35]

Back to the chassis. With the transmission and transfer case removed, we tried to turn over the engine. NOGO. Ran when parked… 6+ years ago…

Let’s disassemble this thing and see what the issue is. The plan is to strip most of the components off of the engine and pull the cylinder head off while it is still in the chassis. Then move the block onto an engine stand.

[Dustoff35]

Not good. After removing the cylinder head, we found corrosion in two cylinders. Apparently moisture entered the engine at some point. Is it salvageable?

The plan is to fill the affected cylinders with Evaporust and let it soak in and dissolve the corrosion for a few days.

[Sammconn]

Are these blocks sleeved?
If so there is the answer.
Unfortunate that it’s this way.

Otherwise then oversized and a bore in its future.

[Dustoff35]

Are these blocks sleeved?
If so there is the answer.
Unfortunate that it’s this way.

Otherwise then oversized and a bore in its future.

Not sleeved. I agree. A boring is in this engine’s future.

[EL TATE]

We just continued the assembly, the Torque-King manual has step-by-step instructions and covers all the variants from different automakers and model years. The rebuild kit from Randy’s Worldwide contains all the parts necessary. It is a complete kit.

other than your tech manual pedestal being slightly over engineered, i think this is coming along very very nicely sir 

[JR]

The bores are pretty robust but that is bad. Any can be sleeved if you must.

[Dustoff35]

The affected bores are filled with Evaporust and covered. We continue to strip parts and components off of the engine in preparation for removal from the chassis.

[Dustoff35]

The forklift makes removing the engine from the chassis almost easy. We bolted the block to a new 2000lb capacity engine stand.

[stlaser]

I have an almost identical stand, to which after grinding out welds and rewelding it I then built a side mount for the Cummins. Stand may be 2k rated but that Cummins is long front to back.

[JR]

Think thats why some stands mount the motor on the side.

[Dustoff35]

I have an almost identical stand, to which after grinding out welds and rewelding it I then built a side mount for the Cummins. Stand may be 2k rated but that Cummins is long front to back.

Agree. It’s a heavy engine. If I do another one, I will make a side mount.

[wilsonphil]

A realman would build a real Cummins stand, this is one I threw together awhile back

[Flyin6]

A realman would build a real Cummins stand, this is one I threw together awhile back

Tossed that together did ya???

(Spare Falcon parts??)

Engineers...

[stlaser]

Nice work Phil, I imagine you just had those cost effective pillow blocks laying around????? 

[TexasRedNeck]

I’m wanting to build something like that for my LB7 block


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[Dustoff35]

Very nice engine stand.

[Dustoff35]

Disassembly of the 12v begins. The Evaporust appears to have done its job, and although the cylinder affected cylinder walls look a little rough, we should be able to get the piston s removed.

[wilsonphil]

Nice work Phil, I imagine you just had those cost effective pillow blocks laying around????? 

One of the very few advantages of LA was there are lots of surplus houses, I think I paid $50 for the pair.  Picked up the very nice casters for 100 for the set of 4. Is all bolt together so I can roll it under a bench when not in use.  Total build cost less than $400 if I remember correctly.

[stlaser]

Sweet 

[Dustoff35]

We removed the camshaft, crankshaft and the pistons. Only one of the two pistons with corrosion in the cylinder bores required additional effort to remove. The Evaporust did an excellent job of loosening the pistons and rings. The two affected cylinder walls don’t look as bad as they did right after cylinder head removal.

[Dustoff35]

With the engine block completely stripped of parts, we power washed everything and placed it on a pallet until it goes to Haisley Machine in Indiana.

[JR]

Mines been undercover and rotated free when I got it, some time ago! Only had 80K I was told.

[Dustoff35]

Mines been undercover and rotated free when I got it, some time ago! Only had 80K I was told.

Keep it covered! This engine did get water/moisture in it at some point.

[Dustoff35]

With the engine out, disassembled and at Haisley Machine, it’s time to start stripping the remaining parts from the chassis. We will definitely need to take out the king pin Dana 60 front axle and the fuel tank.

[Dustoff35]

We continue to strip the ‘91 chassis. Here is the Dana 60 front axle. Once the frame is stripped and moved out of the way we will dig into the axle to see what surprises await…

[JR]

Looks like a clean axle.

[Dustoff35]

Looks like a clean axle.

It’s OK, rusty but not too much pitting.

[Dustoff35]

Everything we want to keep is stripped from the ‘91 chassis. We will put it outside in an out-of-the-way location in case we need to check measurements or bracket locations in the future.

[wyorunner]

Not sure what your build plan is, but I didn’t measure any brackets going from the 92 donor onto the 74. Just bolted it all together.

Had to cut out the divorced transfer case cross member on the 74 frame, and drill some holes for the 92 transmission cross member. Everything else was direct bolt on.

[JR]

Frame looks pretty good. No obvious pitting and just surface rust.