1971 K10 Stepside - Getting a Roller Roadworthy

[Richard]

Originally Posted by pjmoreland

I noticed that the front output has what I would consider excessive in-out (axial) play. The yoke is clamping the bearing to the shaft adequately. The bearing is sliding in and out in the housing by almost 1/8". I pulled the bearing out, and I can still see machining marks on the housing bore, so it doesn't appear that the bore is worn. It seems that the seal housing is the only thing that constrains the bearing from moving, and it has a decent size gap between its inner surface and the bearing. Is this slop normal??

Great job on the work here. I enjoy following along. The front seal housing does hold the bearing in place with the snap ring on bearing. Think you will notice the small bit of movement going away once the yoke is installed and tightened up.

[pjmoreland]

Originally Posted by Richard

Great job on the work here. I enjoy following along. The front seal housing does hold the bearing in place with the snap ring on bearing. Think you will notice the small bit of movement going away once the yoke is installed and tightened up.

Thank you, and I hope so, although I noticed the play before I removed the yoke. The nut was very tight. Just as a test, I reinstalled the seal housing without a gasket, and I reinstalled the yoke and nut, and the play was reduced significantly.

[pjmoreland]

I believe I found a large contributor to the end play on the NP205 front output. The snap ring on the bearing is worn significantly on both sides. It has an angle worn on the back of it in the shape of the bevel that is in the hole in the case. It also has a step worn on the front where it contacts the seal retainer. I got a new snap ring, and it has a larger O.D, as well, so that should give more contact area.

[pjmoreland]

Spent some time today assembling components on the dash:

Speaker
Radio
Heater wiring
Ignition switch

[pjmoreland]

Glovebox
Ashtray
Wiper motor screw

[pjmoreland]

Also, today I took the NV4500 tail housing over to a friend's house to borrow his mill to make the needed modifications to make it work with the NP205:

Rear shift rail clearance notch
Idler gear shaft nut clearance notch
Input shaft seal housing screw clearance
Extended seal housing bore by 1/8"

[pjmoreland]

Today was a long day of working on the truck. Started off with a litte work on the NP205 while I wait for a new front output bearing to arrive:

Replaced rear output seal
Installed new rear yoke (1310)
Replaced front output seal
Painted new front yoke (1310)

[pjmoreland]

Next I spent a little time wire wheeling some parts that I will be painting with leftover epoxy paint that I will have from a batch of dummy filler necks I'll be making this week.

[pjmoreland]

The next project of the day was to start the process of replacing the 2wd main shaft in the NV4500 with a 4WD version. Several components are a press-fit onto the factory shaft but a slip-fit on the replacement, so there was a lot of puller usage. Started by removing the tail housing and the top cover. Then removed the 5th gear and shift fork.

[pjmoreland]

Here's the driving fifth gear removed.

Then the speedometer tone ring had to be pulled off. It was on there super tight, and it had to be pulled a long way before it loosened up.

[pjmoreland]

The driven fifth gear also had to be pulled off. Confirmed that it is indeed a slip fit onto the new main shaft.

[pjmoreland]

Removed the input shaft next. Four bolts and a little tapping with a rubber mallet, and it was out.

[pjmoreland]

The main shaft assembly could then be lifted out of the case. It was heavy and awkward.

The gears down in the bottom of the case look good, and they spin smoothly.

The rear main shaft bearing was pressed on, so time for more pulling. Had to run to a hardware store in the next town over that closes an hour later than the local one to get some couplers to allow the puller to reach all the way to the bearing.

[pjmoreland]

Disassembled the main shaft assembly next. There were a few stubborn snap rings, and one synchro plate on the front of the shaft that had to be pulled off. Had to grind down the tips of the puller jaws to fit in the narrow gap.

[pjmoreland]

Here are the old and new shafts side-by-side.

I reinstalled the main shaft components onto the new shaft, but had to stop there because I had to order a new rear bearing. It should be here on Tuesday.

I'm tired!

[loudchevy]

Awesome work, I love the large helical gears in these boxes. Just pure beef

[pjmoreland]

Originally Posted by loudchevy

Awesome work, I love the large helical gears in these boxes. Just pure beef

Thank you. Apparently these transmissions aren't very sporty to shift, but that's just fine on a vehicle like this.

[Ol Blue K20]

You make it look easy

[pjmoreland]

Originally Posted by Ol Blue K20

You make it look easy

My knees would say differently. That's what I get for doing this work on the floor.

[pjmoreland]

Spent the last two evenings making dummy filler necks, but I did have enough epoxy paint left over to paint these parts.