1979 Dodge MB400 cube van conversion

Leggs got me a great Christmas present based on the almost, as of today, 23,000 views this project has generated on this forgotten old forum:
 

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So thanks to you mystery readers for making this old truck world famous.

Happy New Year!

We hope to see you on the road
 
3 way propane equipment

I first saw these portable propane 3 way chest freezers when I worked in the bush in the 1980s.

I bought my first used Unique freezer in 2011. It was already 10 years old. It was built in South Africa. They used butane fired refrigeration in remote areas for years. Obviously solar has changed all that. All the new propane units are from China.

I realized my write up for the Cubicle has no photo of the built in fridge with the separate chest freezer so I took one yesterday. The chest freezer was new sitting in an abandoned body shop and cost me $300. The fridge is used, about 30 years old, and was $75. The tank slung underneath was in a 1982 Sportsmobile I flat towed home from Atlanta. You can see why I went with propane instead of solar. Plus we don't get guaranteed sun drenched boondocking sites here. That said we run interior- fridge, freezer, and 2 burner cooktop. Outside- 3 burner camp stove, Mobicool portable 3 way chest cooler, grill, and soon a propane firepit. And we make ice instead of buying it. Leggz actually brings homemade frozen bread dough along.

The fridge, freezer, and cooler run off the second alternator I put on the hemi. Then propane when we are camping.

I've never seen anyone else with the 3 way chest coolers or a 3 way freezer on the road. People can't understand how the flame and warm exhaust make for cold beer. Me neither...
 

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We're on the road to the southwest and loving the ease of driving the Cubicle with the 2007 hemi engine and the A518 transmission.

I met Zack today. He has a 1977 Ford C class RV and was parked beside us at a truck stop.

He recognized the license plate frame from the photo here and introduced himself as a reader of this forum.

Great to be recognized so far from home by an energetic home builder like Zack. Travel safe. Find a way to send me your email address. I have a Cubicle tee shirt I forgot to give you. Not used to all the publicity!

If you see us say hi.

Cheers,

G.

24,122 views!
 
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Sensor failure

The heart of the system that gets the accelerator pedal position information to the engine computer is an accelerator pedal position sensor (APPS).

These were mounted under the battery in the 2003 and 2004 Hemi trucks to convert the mechanical pedal motion into an electronic signal. Later trucks got a sensor built into the pedal.

The advantage for engine swaps like this one is that it allows the addition of another cable that gives pedal position info to the transmission through what is called a TV or throttle valve cable. The old school transmissions like A727 or A518 (used here) will burn up unless they match oil flow to throttle position.

In other words the box with the pedal sensor in it has another cable attached to the sensor that moves a lever on the transmission matching throttle position.

A box that ties the gas pedal, position sensor, and TV cable is available through the aftermarket, but I built my own to save money.

The APPS I had was used. On the 2250 mile drive I noticed a flat spot in the throttle where there was no change in engine tone. I hooked up my phone app to the OBD2 port on the engine computer and was able to monitor relative throttle position while driving. That confirmed a flat spot between 42% and 84% only on the way up, but smooth on the way down. Eventually the engine computer said no, too many out of spec throttle positions, and left me in the left lane of I-40 with no throttle. Luckily I coasted up an off ramp and pulled over.

The engine would idle so I left it running with the 4 way hazard lights on. I cleared all the road trip junk off the doghouse, put the dogs safely in their crates in the back, and pulled one bolt out of the doghouse. I hoped I had left my spare APPS on top of the engine next to the box with the operating one.

Pulling the doghouse off on the side of the road at night is a pain in the ass. After the first bolt was out I stopped and thought the situation through.

Even if the spare APPS was sitting on the motor I would have to clear the engine computer error codes to get it to work properly. Why not clear the codes now and see if the existing APPS would work. I cleared the codes, fired it up, and the throttle worked. I promised the gods of motor fuel acceleration I wouldn't go too deep into the gas pedal and we were off without pulling the doghouse.

She made it all the way to Arizona.
 
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AZ and the fix

Getting to our Arizona destination was great. A bit goofy speed wise with the pooched APPS, but liveable.

Next issue the HOA or homeowners' association.

Staying with family is great. This community used to let you park an RV in the main club parking lot while visiting. Not in your host's driveway, but close by. No camping, just parking.

That parking salvation is no more. You apply and can receive a 24 hour RV loading and unloading permit for your host's driveway.

A one week stay means two 24 hour permits and somewhere else for the van for 5 days. Nearest town is 8 miles away.

I pulled in to a repair shop in that nearby town with doors high enough for the Cubicle and booked an oil change for the middle of my stay. I asked the young man if I could drop off the van a few days before the scheduled change and he agreed. The shop is closed Sundays.

So I dropped it off 24 hours later. I checked on it through Saturday and there it sat.

Sunday I went to work. I had pulled all my tools out before dropping it off so I gathered those and pulled the doghouse.

I had received a new Mercedes spec APPS from eBay. A video by some hemi gurus pointed out that Mercedes and Dodge, with the same owners in the early 2000s, used the same APPS. They are available singly for about $60. The Dodge piece is not available from Mopar. It is available as TH456 from Standard/Bluestreak buried inside the box that bolted under the early hemi truck batteries. That box is called a bellcrank. $350 from Rock Auto.

The new Mercedes piece fit perfectly. Size, shape, and bolt holes aligned perfectly.

The plug for the wiring harness was out to lunch. No pig tail wiring repair either. Not a lot of Mercedes sitting in local yards for a connector either.

So off to O'Reilly auto parts to get a TH456 for a truck only built in limited numbers 20 years ago.

Timothy at O'Reilly said he could indeed get one, and could match Rock Auto's price. Only issue was it was in his warehouse and I would have to wait for it.

For 2 stinking... hours!

Credit card in machine. Bellcrank delivered.

Sunday was a great day to install it.

Test drove it while monitoring throttle position and with doghouse off. Worked fine. Sure got hot when radiator cooling fan kicked in. Yikes that thing can really move air.

Oil change next Wednesday. Three more days of "storage", and then on the road again.

24,288 views! Sign up and say hi will ya!
 
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The Cubicle made it home today from its inaugural trip to the southwest.

About 5,000 miles total.

A special shout out to Jerrell at the O'Reilly auto parts store in Toledo for helping me get the right transmission fluid for the A518 as I blew through town.

More news on what needs fixing after some sleep, but suffice to say the Cubicle made it home!
 

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The team at Hotwire in Mena, Arkansas posted a photo and some nice words about the Cubicle's recent visit.
 

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List of broken stuff:

2 worn out shocks, both way undersized. One lost its lower rubber isolator, rattled to beat the band, and was cut out and replaced in AZ. Both were leaking after the beating they took on the potholes we hit on the interstates. I found a Monroe RV shock and had 2 shipped. Much larger piston than the econo crap pieces in it. #555037 $45 ea at Rock Auto

I'll replace both when I do the driver's side upper control arm.

The Dorman add a drain plug kit. Have to pull the transmission pan. Underside of Cubicle well oiled. Back windows too.

Lower rad hose clamp needs a turn or two.

Speedometer not working. Cable needs to be longer. May go to electronic unit from old 1993 Dodge. I have a Dakota speed sensor and control box bought for anticipated cruise control installation.

Move rad fan controller to drier location.

Add way more transmission cooling capacity. This may scale back once transmission leak is fixed and it will hold constant amount of fluid.

Raise auxiliary alternator voltage to compensate for what freezer and fridge pull when operating. 17 amps. Plus 5 amps to get alternator fields working. Plus enough to keep NVLA battery active.

Pull filter off oil fill vent pipe and plumb into intake. Running wide open gets a bit o stink back into cab from poorly sealed dog house.

Did clean up all the dog barf from our last night in Illinois. Shop vac to the rescue.

I'll post photos when I get these done.

Be well.

24,770 views. Say hi will ya!
 
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Hi,

Ran the auxiliary alternator on a trip to VanFest earlier this month. Upped the voltage to make up for the 18 Amp draw that the fridge and freezer chew through on DC power. The big battery came out with perfect voltage and the fridge and freezer were cold.

So it is possible to add a second alternator to a hemi and jam it all under the hood/doghouse.

Also added a little badging to the back end. One from the Aspen engine donor and the other from a Nissan.

Hits on this forum now up to 26,957 so somebody's watching. Please sign up and post your thoughts. Good or bad.

Cheers.
 

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