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North Florida Bus Conversion

C. Fred Hobe
Rt. 2 Box 169
Madison, FL 32340
1 850 673-8446

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"Tips from a Pro"

Installing a generator in an MCI

     These are my tips on gen-sets and how to install them. I will start by giving you my view on sizing your generator. If you are building a all electric coach, it is my believe that you don’t need more than a 10KW. Have it wired 240 volts. When you wire your appliances, put one air conditioner on one leg and the other on the other leg, as you always run your front air when on the road in hot weather and heat in cold weather. Put your refrigerator on the same leg as your back air, as a refrigerator draws little load. I also put my 20 gallon hot water heater on that leg. Put a switch on it so that after it has the water hot you can turn it off. I put this switch at the bath room sink counter. Now I divide up the lighting between the 120 volt legs. It is impossible to get a perfect balanced load, so don’t worry about it. You don’t have it in you home either. But get it close.

     I have an 8KW in my coach and it does just fine. The reason is that one air conditioner draws 1300 watts and the water heater draws another 1500 watts, one or two light might use another 50 watts. That is about half the capacity of the gen-set. All the manufactures tell you to run you generator with around half it load capacity, as that is were it works the best. At that load it will use around a quart of fuel a hour. Some use a little more. And you aren’t pushing it to run hot.

    Now you have to make up your mind as to were you are going to install it. I used the bus air conditioner condenser bay as shown in pictures below. If you use the small gen-set, an 8KW  will fit in this bay with a slider on it to pull it out to service. You have 28 inches from the floor to the roof. You have to remove the center post by cutting it out as show in photos. Now you have to close in the top section. I weld a piece of 1-1/2 inch angle iron in this space, then I put a plywood roof in it. I now insulate this area, it will take 4 inches. I now close in this opening with the stainless steel siding I took off the lower part of this opening.

     After you have removed all the pipes and electric connections from this area, also the big round air discharge vent, you can get ready to cut the bottom of the plywood in the back of this compartment, behind were you took out the discharge vent. Start at the corner and cut up 4 inches. Now cut straight across to the other side stopping at the post. Cut down to floor and remove this strip of wood. Now pound down the pan that is inside the condenser compartment. You should have all this out by now [big job]. Now you are ready to measure to make your slide out.

     If you chose to use a bigger gen-set like a 15KW then you will have to take the whole section of plywood out also you will have to reroute and move up some of the pipes that are in the condenser compartment as you don’t have enough height to put it in as photo shows. You also will not close in the top as described above. Your gen-set will slide in going straight into the bay and you will have to build a different door to close it. On the front side of this compartment it makes a good battery compartment and you can install 4 - 8Ds in it with a little modification. Don’t forget it needs to be vented.

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Genset opening
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Finished genset opening and Genset installed in MCI condenser compartment on a slide out by Next Generation
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Genset exhaust and disconnect
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Genset on a slide-out in service position and 12.5Kw Turbo
genset by Next Generation

How to build your Gen. Set slide out.

     Material that you will need. One length of two inch channel iron, one length of 2 inch angle iron, 4 ft. by 2 inch by inch flat iron and 10 Torrington # crsb-22 bearings or Mcgill cf-1-3/8-sb. Now cut two pieces of your channel iron 52 inches long, and two pieces 17- long. Weld these to make a rectangle. Set both pieces of channel iron inside of the 52 inch pieces, with the channel facing out. Weld the 17- pieces of channel with the flat side facing out.

     On the angle iron, cut two pieces 53 inches long, one piece of angle iron 21 inches long and one piece of flat iron 17- long. Now take them to your drill press and drill a 3/8 hole one inch down and one inch in, on both of your long angle irons. And a hole every 11 inches back. Make sure that they are exactly 1 inch down-make a jig, so you are right. Weld these together with the angles facing in. You will have to notch the angle iron on the back so that the back piece can lay flat to the bottom when you weld. Make sure that you are making it square The front is the hole that is 1 inch in. It should be 21- wide when complete. You can install your bearings in the holes and tighten, you will have to put washers on the inside and on the out side.

     You should be able to slide you channel iron frame into the angle iron frame. Now you can slide this into your coach in the hole that you cut described above. Pull your slide in, out so that the back of the slide out is right up to the back of the plywood in the condenser compartment. and weld a stop on the outside of the angle iron frame, one on each side. These should be about 3 inches long with a bearing that rides on the channel iron -  this keeps it from tipping. The bearing should be just touching the channel iron, Now weld a short piece of flat stock that will slide up to and touch the top bearing brace. This is what gives you your length of slide out. Do this before you weld the front down. Because the pan is inch higher you will have to put a piece of iron on the bottom in the front. Now make sure that it is laying flat on the inside of the pan, and weld it to the rail of the coach 1- inches in from the side so that your door will close.You now can drill inch holes down through the bottom. Make sure that you measure and come out in the flat place on the under side of coach. I use two bolts on each side rail one near the back, the other half way up. Check to make sure where your fuel fill tube is that goes to your auxiliary tank is on MCI's 7 and 8s.

More coming on how to install you Gen Set on your slide out. Fred

Tip on easy way to hook genset to fuel tank

Cut a piece of flat steel 1 and 1/2 by 1/8 thick. Then cut your copper tubing so that one piece is about 6 inches off the bottom of your tank, Cut another piece about 7 inches long. I use 1/4 inch copper tubing. Now drill two holes about 3/4 inches apart near the center of your steel plate the size of your tubing. Now out toward each end drill two holes that will take two sheet metal screws. Now lay the flat steel on top of your tank, And screw it down to the tank. Now take your 1/4 drill and drill two hole through the holes in the plate, this makes it in perfect alignment. Now take the plate and install the copper tubes so that they stick out about 2 and 1/2 inches from the top of the plate and braze them in. Make sure that they are straight down with no air holes around them. Now drill your 1/4 inch holes in the tank to the next size larger bit. Now put Silicone motor sealant on the plate and install it and screw it down.You now have fuel fittings installed and they won't leak. Hook up your rubber fuel line and the return line on the short tube and you are ready to run your generator. Pictures of new 12.5 turbo gen. set made by next generation generators. They have a Kubota Motor and are very well made and the price is right 5K .Also picture of same gen set installed in condenser compartment on MCI on slide out.

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Flat steel 1 x 1/2 x 1/8 thick, plus copper tubing for pickup and return lines. Pickup and return copper lines brazed in to mounting plate.
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Silicone motor sealant on the plate and installed Fuel lines exiting tank and supported

Make your coach breathe better.

     When I started to look at the way MCIs pull in the air to the motor, I was sure that I wasn’t getting the air I needed for the turboed motor. I went and bought a vacuum gage and installed it on the air intake line. Sure enough it was pulling about 15 on gage. I thought that the air filter was bad. Went to junk yard and bought a big dry air filter from a Freight Liner cut in the air ways for the air compressor and installed a new $80 Donaldson filter. I cranked it up still was pulling 6 on vacuum gage. The newer MC9's have a big opening above the radiator on drivers side. I then cut in a 12 inch by 6 inch opening and installed a louver over it, in front of radiator. This location is out of the vacuum created from the air going past the factory opening which is on the inside left side of the screen. I now pull a very small vacuum. Installed K&M filter, very expensive. It is suppose to breathe much better. It still pulls a small amount of vacuum. Same as with standard filter. But coach is getting better mileage and no black smoke under hard acceleration.

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Picture of vacuum gage installed on natural aspirated. Best check on filters performance.
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Water pumps in your coach.

     How many times have you been on the road, tired and want a good shower, and that 12 volt pump that you have just wont put out more than a trickle. Here is a way to get a shower just like the one that you get at home. Go to Home Depot and get a Flotec Model FPOF300AC. This little pump works off your 120volt system it only draws 2 amps and put out twice as much water as your 12 volt one.

     I put a T in the line that runs to the 12 volt pump and install the 120 volt pump. Hook it up with a check valve, and tie it into your water system. You need a pressure switch that is set at 35 pounds pressure on it. Run the power to a switch in the bath room. Now you can turn it on and off as you want. This pump is very quite, and you can use it as a spare or use it all the time.If you need a lot of water at one time you can run both pumps at the same time. Put a hose fitting in your bay and hook up a hose and you can use it as a fire fighter if needed.

How to build a air braking system for under $200.00

     First you need air cylinder I use a Duramaster #DS1506ms4a2. This cylinder has a 6 inch stroke. You need the a clevis that goes on the bottom, also the air muffler # 046060006. The cost of these three items is $111.75. Next you need 3 male air couplers 1- 3/8 to1/4 reducer 2- quick couplers and 25 feet of good air hose, cost $25.00. You also need an air regulator. Set it between 50 and 60 pounds. This will put about 80 to 90 pound of push on the ram. Now you need to make three things, one a plate that the cylinder base fits on that bolts to the floor of your TOAD. Then you need to make a flat plate that turns under the bottom of brake pedal. This also has a clevis welded on it. And you make a piece that fits on the clevis on the brake pedal that screws into the ram on the cylinder. Now all you need to do is bolt the back of the cylinder on the floor board with the ram having about 4 inches of push. I then take a bunggee and go around the plate that hooks to the brake pedal and pull it back and hook it to the back of the cylinder. This releases the brake when you take your foot off the brake of your coach. You now run your hose through the fire wall of Toad and route it out to your hitch. Now on your coach route the air line from the block were your air lines run to the wheels . Put a T in this line and take off to the back of your coach. Put a quick coupling on this at the hitch. Now when you are ready to hook up all you do is couple the Toad to the coach through the coupler at the back of coach. You now have very good brakes on your Toad that works when you put on you coach brakes. Be sure that you push your brake a couple of times before you start as the vacuum booster on Toad will have at least 2 brake pushes on it, this gets the vacuum tank drained. If you don’t your wheels will slide if you don’t do this before you start.

     This system is better than the $500 plus systems that I have seen. All you do to take it out is take two pins out and release the bunggee. Takes about 15 seconds.

This photo shows all the parts you need. The black parts are the ones you need to make.

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This photo shows the system installed.
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Installing gas struts on baggage doors

Go to most any auto parts store and find a strut that has about 100 pounds of lift, and about 8 or 9 inches of travel. Now measure from you hinge a little less than half of the travel and weld you point of attachment, 31/2 on 8 inch and 4 inches on 9 inch travel. Now open the door to the angle that you want it to be in when you have it open as far as you want. Now weld your bottom bracket on. Put this bracket close to the door when it is closed, but make sure that it will clear. On your top bracket make it a little longer so it will be a little further in the bay. The push on the strut will hold the door in tight. You don’t have to worry about them coming up hard as they have a constant speed. You can turn lose and they won’t slam up. I install two on each door so that they pushing the door even. That way they don’t tear the rubber hinge.

Tip on closing sides in and installing windows

First you need to know exactly were your windows are going to go. Make sure that they are in the center of the bedroom, not all on one side or half in the closet. I now weld 1-1/2 angle iron from the roof to the built line about 3 inches from each side of the window opening, with the flat side toward the window. Then I take off the built molding and the rain gutter. Next, take all the rivets out of the roof along the gutter line and all the rivets along the built line. Make a mark just below the built, so when you drill you can hit the same holes. Next pry up the roof from the 1-1/2 square frame. Now cut your sheet metal. On a non roof raise it is 291/2 inches on MCI's and about the same on others. Slide it up under the roof and position it just above the bottom line on the built line, now put a temporary rivet in the corners. Next get it as hot as you can to expand it. Start your rivets from the center and work to both sides keeping it hot all the time. After you have it all riveted down it will be real tight. I use buck rivets, the kind that you have to back up. Now it is time to cut your windows in. Get them before you start so you know there measurements. I now place them in position and mark,  then cut out the opening with a saber saw using a fine tooth hack saw blade. I now form in the inside of the opening with 2 by 4s, and drill and screw them in to the 1-1/2 angles that you welded in. This gives you a good strong support to install your windows to. Don’t put windows in till after you have foamed your coach as it is very hard to get off. I also paint the out side at this time. After the coach has been foamed I don’t like to use large windows as the more glass the harder it is to cool and heat. If you think that they look to small on the out side you can out line them in your paint scheme. When ordering your windows they will ask you how thick your walls are when you are finished. Make sure that you give them the right thickness. Most are 2 to 2-1/4 inches. if you have any questions just ask.

Updating the front

     If you have to replace your front skin, this is how to make it look newer. I think the original round turn signals make the coach show their age. Also note the upgraded mirrors.
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Tip on up grading tail lights on MCI 8

     You can buy the square tail lights from most trailer sales yards. They are used on quite a few trailers, cost about $8 a piece. It takes 4 red and two yellow. On some it comes as one unit, I think Coachman uses the one piece unit. Now take your tail light frame out and cut the center out. Cut to fit the new tail light bracket. Spray paint the frame and install new tail lights. You will have to install 24 volt double element bulbs. This is the time to polish your S.S. before you reinstall the tail lights.

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Tip on how to save on battery cost.

If you are only starting you coach on 24 volts and not using you coach air you don’t need 8D batteries. You can go to Wal-Mart or any parts house and buy the heavy duty light truck battery they have, 950 amp hours. They sale for about $60 bucks. Buy two and you have 1900 amps of starting power. It will start you coach in any kind of weather. These have a warranty of 8 years and a two year free replacement. On 8Ds they cost over a $100 and only have a one year warranty. They are much lighter to install and you can use it in a emergency in your toad. I have not seen any difference in how the coach starts. Big saving in money and you can replace them any place you are, as Walmarts are all over the country.

Tip on hooking up your gen set to your auxiliary fuel tank on your MCI8

     Take off the cover on the top of your tank an drill a 1-1/4 inch hole using a hole saw. In the top of the tank being careful not to get to many saw shaving into the tank. I put a vacuum cleaner hose up on top as I cut. Now buy a one inch pipe flange and the plug fitting that screws into it. Take it and drill two 3/8 holes in it they will be close together. Now take two pieces of inch copper tubing, one about 27 inches long the other about eight inches long and braze them into the cap. Let the long one stick out about 4 inches the short one about 2 inches out. Make sure that you sweat them in so that you don’t have any leaks around the base of the tubs. Now I use a good silicone gasket material black type and drill and screw it on top of the tank. Install the cap with the two pipes in and you have your feed for your gen set. I now run my fuel lines to gen set along the bottom of the floor of the coach to the gen set and you have a nice neat hook up. The long tub is feed line the short is return.


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