6x6 Power Wagon Project

[Greg Coffin]

Thanks Tim. I was looking at the same distribution box the other day. It looks pretty handy. I had been thinking of running some 4-wire to the back, but then you got me thinking about fuel sender, back-up lights, trailer brakes, etc. So 7 wire it is. Time to find a good variety of wire colors.

[Desoto61]

I would look at http://www.wirebarn.com/. They have most of what you'd need, but if nothing else the TXL/GXL wire is nicer stuff than you will find at most auto parts stores, and they have lots of colors and handy color packs. The insulation on the is much tougher than the PVC that's used on most parts store wire. It's the same stuff used on modern automobiles.

I would think a pack of 18 ga. and then maybe some specific 16 or 14 ga for the heavier stuff.

[Greg Coffin]

Thanks Damien, those wire kits are exactly what I was hoping to find!

[Greg Coffin]

Update - Color Choices and Speedo Repairs

I've been slowly pecking away at the 6x6. We've gotten a lot of little stuff done in the last 2 months in preparation for the return of the cab and front sheet metal. We've also made some long-term decisions that I'll run through.

Color choice: We ended up choosing a medium green for the cab and front end, and black for the fenders and interior cab panels. It's almost an olive color, but slightly darker. I think it will look great on the truck, and will fit the military items we are including on the truck, like the rear bumpers, and M37 tail light and front marker lights. We are using a single stage paint, and decided to go with a semi-gloss sheen. I didn't want the truck to look too shiny - it's not that kind of a truck. The cab, hood and radiator cowl should be done this week. The fenders and interior cab parts will be done a couple weeks later.

Dump bed and back of the chassis: We decided to delete the dump bed for the 6x6, and instead we'll install it on the '62 WM300, which is next in line for restoration. The tail ends of the 6x6 frame rails had been lopped off with a cutting torch at some point in the past, and we had been debating whether to reinstall 1" stubs, or just leave them bobbed and ugly. With the deletion of the dump bed, we were now able to install bumpers on the back, since they would have interfered with the tilt of the bed. The WC bumpers stuck out a long way, so we opted to install M37 bumpers and lifting shackles, along with modified M37 tail lights. The tail ends of the M37 frame sticks out 3" from the rear cross member, and have an additional set of bolts to mount the bumpers and the shackles. So we welded on 3" extensions to match the M37 parts. It looks good, though the bumpers tilt a bit toward the center. I may adjust them after the bed goes on if needed. Pictures will be coming soon.

Speedometer repairs and upgrades: Since I bought my first WM300 in 1987, I've disliked how the speedometer is only lit from the left side. It seems cheap to me. Since I was having the original speedometer repaired and calibrated, I took the opportunity to modify the housing to accept a second light socket. I fabricated a baffle to match the original, and hoped that two lights would not be too much light. The results are really great.

[Tom Petroff]

Nice work on the speedo Greg.

Agree the speedo needs that modification.
Tom

[CSCameron]

Very Nice Greg! I wish I had thought about that mod before I shipped mine off for restoration.

Clark

[Greg Coffin]

Rear Bumpers

Saturday my son and I prepped some minor rust areas on the back half of the chassis and sprayed another coat of paint. We are using Sherwin Williams DTM, which seems to be okay. The first coat was too thin, and broke through in a couple places. It got a little chalky too, but subsequent coats seem to lay on better and keep the semi-gloss.

Here are a couple pictures of the rear bumpers.

[Greg Coffin]

Brakes - One Small Step Back

When I installed the new dual master cylinder, I thought it would be a good idea to have the back circuit feed the rear wheels, since it has a larger reservoir to feed the 4 wheel cylinders. But something about the idea didn't sit well with me, so I did some research and found that the rear circuit of the master should usually feed the front brakes. The reason is because the front circuit of the master is energized first when you step on the pedal, which takes up the slack in the rear drums before the front circuit is energized. It's set up this way for disc/drum brakes, but I figure it will work a bit like a metering valve (which I don't have), which engages the rear brakes just before the front brakes, to help keep the truck running in a straight line during braking, and helps reduce nose dive in hard braking. It may not make a big difference, but I figured it would be better to make the change now than try to do it when the cab is in place.

I'm thinking about installing a metering valve and an adjustable proportioning valve in the brakes ystem, but I would like to take the truck out and do some testing first to see if it's really needed.

Here's a picture of the rerouted brake lines on the master cylinder.

[Tom Petroff]

The larger reservoir was used for the front disc brakes that required more
Volume of fluid than the rear drums required.
When the change to all wheel disc the reservoir was changed to one size.

I doubt pedal application has any thing to do with it.

The proportioning valve is needed to control front/rear braking percentage.

That's my understanding?

Nice job on the install.
Looks Great.
Tom

[Greg Coffin]

Thanks Tom, I think you are right on all counts. I originally ran the aft circuit (the one closer to the booster) with the larger reservoir to the rear drums simply because of the size of the reservoir, since it was feeding 4 wheel cylinders and would have twice as much fluid to draw from as the shoes wore in.

I found out that this master cylinder is designed to send low pressure fluid to the rear drums from the front/fore circuit of the master cylinder when the pedal is first applied. They do this to take up the slack between the brake shoes and the drums, so the rear brakes will engage just ahead of the front brakes. I had the lines backwards, so the front brakes were going to engage first, which can cause handling problems.

Once I get some quality braking time with the truck, I'll decide what changes I want to make. I've heard that the rear axles on the 6x6 tend to lock up early when there is no weight in the back, due to each axle carrying half as much load as a single rear. So a rear proportioning valve may be in my future.

[Greg Coffin]

Rear Tail Lights

The tail lights buckets are from an M37. I installed 2-bulb guts into the buckets, one on top for parking lights, and one below for brake/turn. The red lenses are taken from a plastic Gama Goat lens/door unit. I wanted sturdier housings, so I bored out the centers of the aluminum M37 doors, cut out the lenses from the Gama housings, and glued the two together. It will be water-tight and durable. Tastes great, AND less filling!

I'll be doing the same thing for the front marker and turn signals, with amber lenses.

[bilfman]

Looks great Greg! Can't wait to see this beast rolling, excellent work so far.

[Greg Coffin]

Thanks Bilfman. I'm hoping to get the cab back this week or next. I feel like a 5 year old waiting for Christmas morning.

[CSCameron]

Waiting for parts and processes is the worst. Can't wait to see it.

I haven't given up on the brake booster. Still futzing with my PTO trying to get it to work correctly so I can mount all the drive shafts. Once that is done I'll see what room I have left for the booster.

Clark

[Greg Coffin]

Thanks Clark, I will post a picture as soon as it shows up. It may be a couple weeks before I can get it mounted on the frame, which will just about kill me.

Good luck with the PTO. Are you playing with gear lash issues?