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richard5933

1974 GMC 4108 - Custom Coach Land Cruiser

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We are nearing the end of the first stage of the updates/improvements we're making to our coach, so I thought it was time to post a few photos for others to see. We got this coach at the end of last fall, and it was a pleasant upgrade from our earlier 1964 coach.

This coach was purchased in 1974 by the owner of Super Service Bus Company. He ordered it from GM without seats or restroom, and then had it sent directly from GM to Custom Coach in Ohio to be converted in his family's motor home. It saw only light use in the early years, and I believe spent most of its life in one of his company's garages. It came to us largely as you see it in the photos. Paint is original factory paint (in the Super Service livery colors) and the front upholstery is still original. I've reconfigured the rear parlor to have twin beds and a couch.

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Aside from the rear upholstery and new carpeting, the majority of upgrades and work is behind the scenes. We added a new house battery system based on four Trojan L16 batteries, giving a total of 780 Ah of capacity. There is a Progressive Dynamics 70-amp charger for the house batteries as well as a battery-to-battery charger to allow charging from the chassis alternator while on the road. The last piece will be adding the Victron 150/85 MPPT charge controller and 480 watts of solar panels.

The original dimmable 120v fluorescent lighting is still in place and working, and I've added LED 12v lighting throughout. The microwave is the original Thermador which actually works quite well. Two burner electric stove for cooking, and a Norcold DE707 dual voltage (12v/120v) fridge. The fridge will be upgraded to a Vitrifrigo whenever it gets here from Italy. (It was the only one that will slide into the current opening.)

We recently took a one-night shakedown cruise, and in a few days we're heading to Black River Falls WI for the Ho Chunk Pow Wow. Free camping (no hookups) and a great chance to test out the dry camping ability of the coach. This will be our first real trip in the coach and we're very excited. We're hoping to make a long trip to the east coast later this spring, and then may head to New Mexico in early fall. Lots of local trips in between if things work out.

 

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5 minutes ago, desertdeals69 said:

Looks good.  Are you going to Gillette?

Not sure. Since we just declared the coach ready for prime time we haven't given it much thought till you asked.

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37 minutes ago, desertdeals69 said:

Looks good.  Are you going to Gillette?

On second thought, I think so. Just sent in our registration. It will be our first event, so I'm not sure what to expect. That said, looking forward to it.

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Really looks great. Best of luck with it. Hope to see you out on the road somewhere. A gorgeous coach like that will be hard to miss. Safe journey

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Very impressive. Manual tranny? Wanted to be a " Bus Nut" , but trucking just took up way too much of my time. Originally 24volt wiring?

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8 minutes ago, obedb said:

Very impressive. Manual tranny? Wanted to be a " Bus Nut" , but trucking just took up way too much of my time. Originally 24volt wiring?

Definitely manual. I'm starting to get the hang of it, but the learning curve is steep. The chassis is still 24v. House systems are all 12v.

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Nice looking bus. I am to lazy to drive standard any more.

Have you looked at one of the Bus Nut Chapters in your area? 

Bill

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Re/ shifting.  Traveled in many buses as a youngster. That was an important way to get around in the south ( 40's and 50's ). Remember a lot of drivers wearing Greyhound and Continental Trailways uniforms that ground gears. Engine and tranny being in the back made it tough to shift because the driver could not shift by listening to the engine. Seems to me that the Europeans used fully synchronized manual Trannys in their trucks and buses. Not so overhere . You probably have a five speed?  Maybe Kay has a suggestion or two.

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Richard, that is a good looking bus convert. I do have a question or two, one, does this unit have a equalizer on the 24 volt system, if not there are inverters that use 24 volt, My coach does have an equalizer, but it is a 1988 model. Having an equalizer means that you can pull from one 12 volt battery for powering a 12 volt system from your 24 volt, without damaging either battery because of excessive drain from pulling from only one, very handy in my case, and of course all lights are 24 volt except headlights, they are 12 volt, which makes them much easier to find replacements. If you notice most Prevosts has stacked all clearance lights one over one, that way the two are wired in series, so that 12 volt is used in the 24 volt system. There are many tricks that can be used in a convert to make life less difficult. My bus has a 24volt, 180 amp alternator, and since I do not use the bus air, I have a 5000 watt 240 volt inverter, which allows me to pull two roof airs right off the bus 24 volt system, just don't leave them running when the bus is not running. I did like to hear those old manual trannys shifting with an experienced driver, with the old 2 stroke detroits. My coach still has the Detroit 6v92, 335 HP with 1050 ft. lbs. @ 1600 rpm, it is a 4 speed Allison ht740 auto tranny, best fuel mileage is 68 to 72 mph, perfect for most interstates.

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The chassis system was 24v from the factory and still is. All the bus systems are 24v, including dash lights, headlights, marker lights, etc. The only 12v bus system that I've found so far is the circuit for the daytime running lights which provides 12v to the headlights for daytime half-power use. I haven't had too much trouble finding replacement bulbs for anything yet, and what I cannot get from Amazon I can get from Luke. The other things that I've replaced such as driver fan are available in 24v from truck supply houses. The only 12v thing I've installed for use while traveling is the car stereo, and it is tied to the house battery bank.

As originally configured from Custom Coach, about half of the house systems were tied into the chassis battery. With the exception of two pieces (servo for rear window Venetian blinds & actuator for pneumatic step cover) everything has been changed to run on the 12v house batteries. The two remaining pieces were left as 24v because I cannot find 12v replacements for the servo & actuator, and if I did there was no access provided without disassembling cabinetry. Just didn't seem worth the effort, especially since the step cover is only used while on the road and the blinds are usually kept closed since they are behind the TV. All the DC lighting is now LED, and I've added additional lights where there was only 120v lighting installed.

Many of these older Custom Coach conversions didn't have a real house battery bank installed at all. They used the generator 8D start battery to provide power to the 12v systems, and were designed to be plugged in or on shore power whenever they were parked. Obviously this setup was not going to work with dry camping and needed to be changed. Apparently things were done much differently in 1974 than they are now.

We installed four Trojan L16G batteries for a total of 780Ah. The charger is a Progressive Dynamics 9270 which puts out 70 amps. There is also a Sterling 24v-to-12v battery-to-battery charger which allows the house batteries to charge directly from the chassis alternator while on the road at 70 amps. The Sterling is a modern multi-stage charger and a step above just using an equalizer since it won't over charge. We do not have an equalizer, and if I'm running 12v systems while driving I just turn on the Sterling charger.

The last step of the system, which I'm still working on, is the solar. Right now I'm working to make the bus 'solar ready' and installing a Victron 150/85 MPPT charge controller. Panels will follow soon.

Since we have over-the-road a/c and don't plan on running the a/c while dry camping (yet) there was no need for a huge inverter. We installed the PSW Samlex which puts out 2000 watts. Due to the configuration of the 120v breaker panel and the use of a manual transfer switch I was not able to tie it into the existing 120v system and opted to install a few parallel outlets from the inverter. We've got outlets front and rear from the inverter as well as one in the wet bay. Eventually we plan to reconfigure the 120v breaker panel to allow for installation of an inverter/charger which is tied to the 120v system with an automatic transfer switch.

We're planning to be at Gillette and would love to have you take a look at the setup if you're there, and possibly we can see how your rig is set up as well.

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Is anyone interested in getting together in Gillette? Last time in Perry had very few folks there.

I will have a social at my coach if you'll would like. I can post my location on the 12th the day I arrive.

Is Tuesday afternoon the 17th say 4:00 pm, all right with everyone? It will be before any activities begin. Bring chairs and your choice of beverages. 

Herman

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Richard/ your engine looks like an 8V71. They are known to use quite a bit of oil. Probably would be a good idea to carry extra oil with you on the way to Gillette.

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30 minutes ago, obedb said:

Richard/ your engine looks like an 8V71. They are known to use quite a bit of oil. Probably would be a good idea to carry extra oil with you on the way to Gillette.

You are correct - 8V71. On my trip from NJ to Wisconsin it actually used almost no oil at all. The engine has less than 42K miles (actual original miles, not since rebuild) so it's really still a new engine in many respects. I do carry a few gallons with us, but unless something goes wrong I don't expect the oil use to go up suddenly.

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1 hour ago, hermanmullins said:

Is anyone interested in getting together in Gillette? Last time in Perry had very few folks there.

I will have a social at my coach if you'll would like. I can post my location on the 12th the day I arrive.

Is Tuesday afternoon the 17th say 4:00 pm, all right with everyone? It will be before any activities begin. Bring chairs and your choice of beverages. 

Herman

We'd love to get together with others, but we won't  be arriving until early on the 18th. We kind of decided to go to Gillette at the last minute, and that's the soonest that we'll be able to pull in.

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How cool is that! A 43 year old bus conversion with 43,000 original miles.😎 Two stroke diesels were the mainstay for many years. As a young driver, I liked the sound of them. 

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Richard, nice looking coach!

Obedb, and its a blown 8V at that :wub:. I also love the sound of them! I keep telling my wife if I find an old tractor with a twin stick and a 12V92 "buzzin Dozen" i'm buying it! 

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Richard.

Your looking good.  Great job!  Not many coaches like yours, still rolling down the road. Your going to really stick out in Gillette!  Beautiful "Old" Coach..:)

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That looks great! I was always told the correct way to drive a detroit diesel was to first slam the door on your hand and then get in an drive!

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