| Author |
Message |
cgoodwin (208.12.28.149)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, June 13, 2004 - 3:32 am: | |
Has anyone ever connected the factory air compressor to a small diesel motor??? I am planning my HVAC system and it occured to me that it should not be nessisary to install another AC system, when I already have one! I looked and my compressor is belt driven from the motor and there seems to be plenty of room to install another small diesel motor driving a pulley and in turn, the on-board AC.... Has anyone done anything like this? If not, why???
chris |
FAST FRED (4.245.212.203)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, June 13, 2004 - 5:02 am: | |
GM attempted to do it in about 1950 on the early 4104.
Was a failure as the unit was too hard to maintain.Leaks took a couple of pounds of F-12 a week , and the pony engine was not very reliable.
Today with super sophisticated die leak dectors , there is a chance it might be made to operate..
Of course you would need some seperate system to use at any campsite as few if any will allow gen sets to be operated on sites.
Even with a rooftop exhaust the diesel stench , and noise would have the other campers repeating the scene from Notra Dame , where they light torches and want to burn Quasimoto ALIVE!
A big 4KW (SW) inverter with the coach alt as power, and carefully hunting down rare 50A campsites is about as simple as it gets .
FAST FRED |
Jim-Bob (152.163.252.199)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, June 13, 2004 - 8:40 am: | |
Actually Fred, GM sucessfully did it from 1953 to 1960 on many thousands of 4104s. The reason was that they did not yet have the 8V-71 and the 6-71 did not have enough power to drive 12 tons of A/C plus climb hills.
They used a 4 cyl. flathead gasoline motor to direct drive the compressor, much like today's truck (diesel) refer unit. One advantage was that a bus could leave the air cond on all day without idling the drive engine.
Though the '50s engineering was primitive by today's standards, they did work & some still work today. |
bobm (68.35.160.48)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, June 13, 2004 - 11:36 am: | |
I use a 2/53 detroit to drive my A/C compressor and a 15KW generator. I have a separate 100 gal diesel tank for the 2/53 and I use the original 4104 A/C gas tank for a spare diesel tank. Works great |
Luis Chavez (Sundancer) (63.204.106.234)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, June 13, 2004 - 12:12 pm: | |
Ok, so I finally bought my bus. 88 MC102A3 6v92 auto. Decisions have to be made, brains have to picked. All electric, or propane? Keep bus air or remove? |
cgoodwin (208.12.28.149)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, June 13, 2004 - 12:48 pm: | |
IMHO You should keep the bus air, hell it was designed to cool the bus in the worst of conditions while carrying 50+ people (each producing an amazing amount of heat). My question is why have anything else?
Fast Fred - you say that the system leaks??? My system does not leak? Are there really bus companies out there designing systems which leak a couple of pounds a week???
How difficult could it be, the on-board system works well even at an idle, since the pulleys are of equal size this means that the compressor will function at 500 rpm, I would think that even a relatively small gas or propans motor should run the compressor, perhaps even another belt could be run to an electric motor when in a camp, a washing machine motor perhaps. As for sound, I have a Suzuki samurai with a 1300cc motor, up to about 1000 rpm you can't even hear it run unless it is silent. I fired it up in the corner of my shop (exhaust vented) last week as it had been sitting for some time... In a shop with 4 people working, two within 20' of it, we all forgot it was idling... I would think that a good muffler is the place most generators and small motors fail. I put a Honda Civic muffler on my shop generator (honds 6.5kw gas) after the factory muffler and unless you are right next to it you would not know it was on.
Soooo, if we take the sound into consideration and do our best to quiet things up, we drive the factory air compressor with a small motor and work out some sort of electric drive for parks (something I will be doing little of)...Would it work???
Bobm - I am very interested in your system, I take it your small motor runs both the genset and the AC compressor! is it the original bus air? How did you set this up? please share the genius!
chris |
Jim Ashworth (Jimnh) (172.151.86.62)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, June 13, 2004 - 2:21 pm: | |
What will you do for the condenser and evaporator fans? They are 1-1/2 hp and 2 hp motors at 24volt. Most likely, you'll run a genset to keep the bus batteries charged to power them. OK, if you need a small motor to run the a/c and another to run the generator, wouldn't it make sense to just run the genset and use roof airs? You will need some kind of a/c when plugged in at a campground so roof airs are needed anyway.
You mention a washing machine motor to run the a/c compressor. I don't think that's enough. The bus a/c is about 100,000 BTU and with 3 BTU/watt and 745 watts/horsepower you need a 44 horsepower motor to turn it. That's just by the numbers, but I have heard elsewhere that 30 hp is not out of the question for the load of an a/c system.
One other consideration, the a/c systems on busses are a high maintenance/high cost item, especially when it is 20+ years old. Conversion of an R-12 system to R134-a(to save on re-charge costs) on a Prevost with only dash air is a $1000 job for parts alone.
The most cost effective thing to do is to remove the bus air and use roof (or basement, your choice) airs with a genset.
Jim |
niles (4.4.112.82)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, June 13, 2004 - 3:28 pm: | |
The OTR a/c on my H3 is all copper , coils and all , and should last over 30 years w/ no abuse or damage - compressor is the only weak point - IMHO it makes sense to have both OTR and basement HVAC as the use of 2 systems doubles the life of each unit and provides for back-up in emergencies - I do not like roof units because of heat gain and clearance considerations
niles |
H3JIm (68.107.62.94)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, June 13, 2004 - 4:11 pm: | |
Niles,
What model of H3 do you have? Did you convert it yourself? do you have any pictures / desciption of your systems and layout?
I hve an H3-41 I am in the early stages of converting. You can email me direct at (jim dot stewart at cox dot net) |
niles (4.4.112.82)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, June 13, 2004 - 5:22 pm: | |
jim,
I have H3-40 VIP , w/ factory OTR A/C , its a
Vantare conversion , the coach A/C is handled by twin 2.5 ton central w/ heat strip basement units w/ common blower (convenient when only 30 amp service available or when 1 compressor dies) - IMHO the beauty of the HVAC systems designed by the 'professional converters' is in their redundancy - w/ the aforementioned dual A/C combined with Auqa Hot w/ multiple heating platforms - a failure of any subsystem will only cripple you and not leave you high and dry - good luck w/ your conversion - also IMHO the H3 VIP is the finest conversion platform out there - wait till you get it on the road - the view out the windshield is like having a "big screen" view of the world that is not inhibited by a cockpit - but have fun doing it YOUR WAY
niles |
Johnny (4.174.67.155)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, June 13, 2004 - 9:32 pm: | |
$1K to convert?! Like, FOR WHAT? |
FAST FRED (4.247.13.199)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, June 14, 2004 - 6:09 am: | |
OF course NO coach systems were "Designed to leak" but hound would pull the drive train every year , about 200,000 miles , so in a commercial life there would be 5 to 8 engines R&R , and mechanics skills vary.
A friend worked in Miami (60's & 70's)for Hound and worked the nite shift (when entire drive packages are routenly swopped every night).
Even with the 8V and reliable drive packages at least half the shops man hours went into air cond repair.
Must have been worse when the motor half of the AC package was unreliable too.
The fittings ect are the finest I have seen , Flares with O rings , all of Substantial heft.
As Freon was so cheap , the loss of a pound or 4 a week was a bucks worth , so they just kept filling.
Might be the equippment is better today , pretty EZ to let your walet be the giude , every time the factory Air eats $2000 decide if it's worth it.
FAST FRED |
Jim Ashworth (Jimnh) (172.147.95.140)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, June 14, 2004 - 9:09 am: | |
Johnny- Retrofit kit with hoses, valves, dryer, etc from Prevost was $716.39. I changed out the compressor too because it was 10 yrs old for another $282.86 for a total of $999.25. Close enough to call it $1000.
Happy I did it. The shaft seal later failed on the compressor and it only cost $30 to recharge it after a new seal was in. Compared to R-12 that was really cheap.
Jim |
Airless in Mississippi (69.92.6.98)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, June 14, 2004 - 11:37 am: | |
Okay okay... I have the factory air. I can use guages and I can use r-134a the bus is converted according to the 12 tags saying so to 134a. Now the questions come in:
Can Someone provide a step by step in order to check to assure that it is setup to be turned on?
The first "bus mechanic" turned a lot of valves and opened others on the compressor attempting to turn heat on this past winter.
Now that we have it turned on there is a Low side connect on the side of the bus near the condensor there is also a low side at the compressor which spot do you put the guages on at?
I have checked the breakers in the 2nd bay port side they all appear to be set correctly. There is however a set of wires going into a hole there that has a small plate covering it, when this plate is removed there are wires taped without being connected to each other or to anything. Any ideas as to what these wires are??? This set of wires is coming from the breaker panel and going into the hole.
This bus is a NJT Mci 9 1987 with a ddec1 and the purple engine replacement. The engine and transmission were alledgedly replaced at the 500k mile mark which was 46k miles ago.
The reason for wishing to have coach air is really simple... IT IS HOT. I understand the concensus is to remove it do away with it etc etc etc. The major reason I have seen is that it leaks, costs tons to be worked on. I own 150lbs of r-134a I own a very comprehensive tool set which is housed on the bus I possess knowledge of Home and auto a/c. I Lack bus AC knowledge. I own DA-book.
I follow directions well if anyone would kindly take the time to help it would be greatly appreciated. I will be more then happy if successful to provide my services to others that may be suffering my same problems and aid them in the labor to get bus a/c running also. Thanks in advance |
Ace (24.28.44.58)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, June 14, 2004 - 9:31 pm: | |
Airless, let me know when and if your in the Florida area. I have a 92 Prevost with Bus air that ABC said would need about 700 bucks of work for them to do in order for it to work properly but said a regular a/c guy would probably do the same fix for about 250 bucks! It TOO has been converted according to the stickers placed all over the unit!
Not sure exactly without looking over invoice what the problem is but think it is mostly seals and change of oil.
I really think they didn't want to warranty the work on this unit that's why the price was quoted high!
I agree that if your bus has factory air, fix it and use it, instead of the butcher job of taking it out!
Thanks
Ace |
Johnny (4.174.103.51)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, June 15, 2004 - 9:58 pm: | |
"Johnny- Retrofit kit with hoses, valves, dryer, etc from Prevost was $716.39. I changed out the compressor too because it was 10 yrs old for another $282.86 for a total of $999.25. Close enough to call it $1000."
Ah, so it was a "factory markup" deal. I know of at least a dozen sysatems useing the original R-12 hoses, valves, & compressors with no trouble. There are four in my driveway right now, in fact, & another in the wrecker I just drove all day. |
john marbury (Jmarbury) (66.82.9.45)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, June 16, 2004 - 12:38 pm: | |
Compressor out of a GM 4905 worked when removed and has been sealed.
If anyone is interested let me know, otherwise it's going to the dump. To Big and heavy to be moving around and seems to always be in the way.
John |
Airless in Mississippi (69.92.6.98)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, June 16, 2004 - 1:25 pm: | |
Ace does not appear I am gonna be able to help you fix your a/c.. No one seems to be offering to help educate me. |
gillig-dan (63.111.68.130)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, August 06, 2004 - 5:24 pm: | |
I am considering adding a split AC system to my '70 Gillig 636 that has introduced my to this bus community a few weeks ago. The system I'm considering has a skirt mounted condenser and fairly compact evaporator unit(30K btu/h). I was also wondering if I could rig up a mechanical system to switch between running the system off the engine or hooking it to an AC motor. I figured I can get by with about 20K, or less, btu's when parked. I should be able to generate that with about 2 horsepower of electric motor, right? I figured this would draw about 20+/- amps@110 VAC. The bus came with 2 small window units (5000 btu/h @ 4.5 A.) that just about keep up as long as I don't open any curtains. There is no air conditioning in the bus yet.
I am looking for guidance to see if my thoughts are correct. I am confident I can make the belt switching system work. I'll probably fabricate a belt tensioning system with air actuators.
The system I am looking at does not have a compressor and I am also wondering what compressor would be a good match. I found a good price on a Sanden 5H14-HD, which is a 8 cu inch model. I am having trouble finding specs on the horsepower that would be required and the RPM that would be the most efficient.
'70 636 Gillig-Dan in Virginia |
gillig-dan (63.111.68.130)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, August 09, 2004 - 1:46 pm: | |
I am considering adding a split AC system to my '70 Gillig 636 that has introduced me to this bus community a few weeks ago. The system I'm considering has a skirt mounted condenser and fairly compact evaporator unit (30K btu/h). I was wondering if I could rig up a mechanical system to switch between running the system off the engine or hooking it to an AC motor. I figured I can get by with about 20K, or less, btu's when parked. I should be able to generate that with about 2 horsepower of electric motor, right? I figured this would draw about 20+/- amps @ 110 VAC. The bus came with 2 small window units (5000 btu/h @ 4.5 A.) that just about keep up as long as I don't open any curtains. There is no air conditioning in the bus yet.
I am looking for guidance to see if my thoughts are correct. I am confident I can make the belt switching system work. I'll probably fabricate a belt tensioning system with air actuators.
The system I am looking at does not have a compressor and I am also wondering what compressor would be a good match. I found a good price on a Sanden 5H14-HD, which is an 8 cu inch model. I am having trouble finding specs on the horsepower that would be required and the RPM that would be the most efficient.
I posted this message previously in an older thread (Factory Air?). I thought I might get better response creating a new thread.
'70 636 Gillig-Dan in Virginia |