MCI 7 ADVICE

[Stormcloud]

Hello,all:

For the past many months, I have been reading your posts, learning as much as I can from your ideas, suggestions, successes (and at times failures) when looking for, and converting a bus.

Armed with this knowledge, we recently purchased an MCI7 8V71 4 speed to convert. Our bus (named PapaBus by our 2 year old granddaughter) will be a no-frills conversion, but still have all the amenities such as queen bed, 3 piece walk-thru washroom, kitchen with a small house-type frig, a propane stove, microwave, a futon-type sofa and a total of 4 (including the driver) captains chairs. 100 gals of fresh water, 100 gals grey-black water, 6 or 10 gal hot water tank, 50 amp electric service, 5kw generator, 2x1000w inverters, yada-yada-yada. I'm unsure about the heat and airconditioning systems, other than I expect I'll be able to keep at least the front OTR air for travelling comfort. But, I'm getting AWAY ahead of myself.

Presently, PapaBus is an almost empty shell. I will be removing the dreaded lavatory this weekend, leaving a whole lot of nothing behind the old drivers seat.
Plans call for an 8 inch roof raise (as I'm already 6'4") and installing MCI9 factory caps in place of the old caps I know I will have to reframe for the caps new height,and extend the caps down to the windshield line with fibreglas. I hope to do this before the end of March, weather permitting. There's still a pile of snow and coldness here in southern Manitoba and working outside at times is not an option.

The big question is.....will the 9 caps fit the 7 roof?

Also, what size and style of rivets will I require for re-riveting the roof edges and caps. I can get maximum 3/16ths rivets locally without special order, and coincidentally an air-riveter that accepts up to 3/16ths only.

The local steel mill can supply 20 guage galvanized or painted flat steel in up to 10 foot lengths or a 35' roll if I choose. I expect I'll use 1.25" or 1.5" square tubing for the new roof supports, and 'glue' the new panels in place where possible.

I look forward to your advice, and I'm sure I will regularly return for more as PapaBus progresses.

Regards.

Mark (Stormcloud)

[Melbo]

Welcome to the madness

You will find a lot of help here

I am unable to answer the questions you have posted but someone will soon enough

I use 3/16 in rivets for all the work that I have done on my bus

Melbo

[Tom Y]

Best bet is call the 800 number for R&M Fiberglass. They make the caps or do you have some 9 caps lined up? If you need their number I will look it up for you. Goodluck  Tom Y

[Stormcloud]

Hi:

I neglected to maention that I do have a set of factory MCI 9 caps available. The 7 presently has an 8 cap on the front;
I think it would look better with 9 caps front and rear.

[DuaneMC7]

Hi Mark,

I think most people bye the 9 caps that R&M make for the 7 roof line, but since you already have the nine caps you should be able to climb up and lay one over the existing cap and see if it will pull down onto the roof for a good fit.
As for framing around the windows and the roof raise you will find that you need 1 3/4'' square tubing to match the existing framing.

Good luck and keep us posted

[Stan]

I keep repeating myself saying that if you cut out the framing in the front and rear roof caps of a MC-7, make sure that you have the engineering knowledge to design and build the new structure to support the front and rear of the bus. Both ends hang on the roof.

[TomC]

Mark- couple of suggestions on systems of works well for me.  Water heater- I use 2-10gal electric water heaters bought from Home Depot-one feeding into the next with the final one powered through the inverter for hot water going down the road.  Cheap-works well-with the only minus, when boon docking, have to run the gen for hot water-although only once a day.

On air conditioning.  This is a hot spot with everyone (pardon the pun).  The cheapest and easiest to service is the roof top.  I have three Coleman 13,500 btu that work well, but the fan is noisy for night time use since it only has a two speed fan-like high and medium.  Heat strips work if you give them some time after turning on, but then you have to put up with the swirling cold air-good for bus warm up if you are not in the bus.  I would advise three roof tops-while two usually do the job, nice to have the third when the outside temps get above 100-along with the redundancy.  Would suggest the DuoTherm Penquins that are three speed and low profile.

On generators- Highly recommend you stay with Diesel.  Are just plainly the most reliable, and don't have to carry an extra gasoline tank, or use a huge propane tank. 1800rpm units will last the longest (over 30,000 hours not unheard of).  But it is possible to get a 3600rpm unit that will be cheaper, smaller and lighter that is as quiet as the 1800rpm units.  Panda has extremely quiet units, although they are expensive.  Rule of thumb- if you only run one A/C use a 5kw; two A/C's-8kw; three A/C's-10kw.  The only propane on my bus is the stove and 35,000btu furnace.  Electric is the two water heaters, wall heater in the bathroom (also powered through the inverter), 12v/120v Norcold compressor type reefer (6.3cu/ft), 2.1 cu/ft Norcold chest reefer/freezer, three roof airs, 2500 watt inverter/charger. 

My house batteries are 2-8D AGM's (510 amp hours).  You'll probably want to go with higher since you'll have an inverter powered house type reefer.  Suggest about 1000 amp hours.  You'll not want to pull the batteries down more than 50% for maximum battery life, so you'll actually have 500 usable amp hours.  If you use an average of 15 amp hours, that will give you 33 hours of batteries.  Make sure you get the best inverter-suggest true sine wave with a 130 amp 3 stage charger built in.

Many, many ways of going. Just my way since my conversion is also a simple one, and going to keep it that way for reliability.  Good Luck, TomC

[Tom Y]

Mark, Back to the caps. The 9 roofline is not nearly as round as your 7.  You may want to see if the will flex that much.  Just a thought.  Tom Y

[Stormcloud]

On closer examination, I don't think the 9 caps will work out as I had hoped. The roofline of my 7 is indeed more rounded. The 'new' plan is to use the existing 7 caps and fill in the bottom edges following the roof raise and structural modifications.

Luckily, one of my helpers is a welder who used to work at MCI in Winnipeg. We should be able to make up suitably strong framework for the raised roof.

The refrigerator I purchased is a Magic Chef with a 120volt type compressor, but draws only 1.5 Amps while running. This is the lowest current draw I have seen on the several mofdels I looked at. I am presently testing the frig operation on the inverter. So far so good.

With all the seats gone, and only 1 parcel shelf left to toss out the window, I'll remove the lavatory tomorrow.Yuck.

Thanks for your advice so far......I'm sure I'll be back.

Regards.

Mark

[TomC]

Just remember that when you have a 120v reefer that pulls 1.5 amps, that's the same as 15 amps at 12v.  With the inverter losses, it would pull more like 17 amps when running.  Compare that to a Norcold with it's own compressor, or a Tundra or Novakool with the Danfoss compressor that pulls only 5.5 amps at 12V.  You're paying for that very high efficiency on the 12v models.  Very important if you're going to boon dock alot-not if you're hooked to a power pole most of the time.  Good Luck, TomC

[Stormcloud]

Good advice; thanks Tom.

The frig seems to work ok through the inverter. I may increase the size of my house battery bank to compensate for the compressor draw. Once the frig goes off warranty, I may change the compressor to a 12v high-efficiency type.

Surprise:

While removing the interior at the rear cap, I discovered some curved windows at the back corners of the Papabus, and a casement-type framework (with an emergency exit crash-bar) which appears to have a fibreglas insert, rather than glass for the centre 'window' area. I'm surprised to see this under the rear cap. I expected to see only steel.

The lavatory is out (except for the metal floor which is inset below the rest of the bus floor). The tank is still in place; once the weather moderates again, it will be removed.

Is there a special way to remove the remaining metal floor, or should I plywood over it?

Thanks.

Mark

[Tony LEE]

There is likely to be rusted framing under the metal floor pan so I would remove it. From memory mine was screwed down with some countersunk screws plus a lot of sealant. The floor insulation will also need replacing.


I like the "The tank is still in place; once the weather moderates again, it will be removed."

You might strike it lucky but most of us who have done it, consider getting the tank out as the single most difficult task of the whole conversion.

[jjrbus]

Nobody has mentioned in a long time that many of the new refrigerators transfer heat throught the walls. Making building in a fridge impossible! The rear coil type are still available.

[JackConrad]

Our new EnergyStar house type refridgerator has the condensor coils mounted next toe compressor in the area under the interior foor compartment. Still pulls air through the grill in the bottom front and pushes it out the back.  Jack

[Stormcloud]

The Magic Chef frig says 'Free Standing Only' ; no coils on the back nor vents at the bottom front so it must expel the heat through the walls also. It kind of limits the layout of the kitchen a bit knowing that the frig can't be built-in, but it's not like we haven't altered the floorplan already.

I've read that the tank can be the most 'challenging' part of the lav to remove. It may have to be postponed (darn as we plan on the roof raise next week.

Thanks for your comments.

Mark