Bus Conversions dot Com Bulletin Board
November 23, 2014, 09:20:55 AM *
Welcome, Guest. Please login or register.

Login with username, password and session length
News: This BB is intended for the sole purpose of sharing conversion and bus related information among visitors to our web site. These rules must be followed in order for us to continue this free exchange of info. No bad mouthing of any business or individual is permitted. Absolutely no items for sale are to be posted, except in the Spare Tire board. Interested in placing a classified or web ad, please contact our advertising dept. at 714-903-1784 or e-mail to: info@busconversions.com.

   Home   Help Forum Rules Search Calendar Login Register BCM Home Page Contact BCM  
Pages: 1 2 [All]   Go Down
  Print  
Author Topic: Temporary Battery  (Read 2177 times)
Jriddle
Hero Member
*****
Offline Offline

Posts: 676





Ignore
« on: February 15, 2014, 07:48:05 AM »

Good Morning

I have one of the 8-D batteries on my spare bus that is bad. I was looking at making a 500 mile trip with this bus. What would be the problem with putting a smaller size battery with the good 8-D for this trip?

John
Logged

If It Can't Be Grown Then It Has To Be Mined
John Riddle
Wells NV
1984 MC9
Jerry32
Hero Member
*****
Offline Offline

Posts: 726





Ignore
« Reply #1 on: February 15, 2014, 07:53:06 AM »

No problem if it is heavy enough to crank the engine. Those *D's were for all the load that used to be in the bus so is not needed any more. Jerry
Logged

1988 MCI 102A3 8V92TA 740
Jriddle
Hero Member
*****
Offline Offline

Posts: 676





Ignore
« Reply #2 on: February 15, 2014, 08:21:28 AM »

That was the answer I was expecting. The positive side of this is not paying for the expensive battery. I just don't see any down side myself but with all the experience out there I though I might be missing something.

Thanks John
Logged

If It Can't Be Grown Then It Has To Be Mined
John Riddle
Wells NV
1984 MC9
Lin
Hero Member
*****
Offline Offline

Posts: 4584

1965 MC-5a




Ignore
« Reply #3 on: February 15, 2014, 09:18:08 AM »

I would say to use a group 31.  As explained numerous times here, a mismatched set may created other battery issues long term, but I do not think the bus will particularly notice.
Logged

You don't have to believe everything you think.
gus
Hero Member
*****
Offline Offline

Posts: 3541





Ignore
« Reply #4 on: February 15, 2014, 07:47:08 PM »

One 8D will crank any of these engines unless it is weak or the weather is very cold. Even one 31 will crank them.

The only reason the bus companies used two was to support the huge AC/heat fan motor.
Logged

PD4107-152
PD4104-1274
Ash Flat, AR
John316
Hero Member
*****
Offline Offline

Posts: 3273

MCI 1995 DL3, DD S60, Allison B500.




Ignore
« Reply #5 on: February 15, 2014, 08:39:50 PM »

The only reason the bus companies used two was to support the huge AC/heat fan motor.

Another minor reason that ours uses two, is our coach is 24V. Won't work on one Cool
Logged

MCI 1995 DL3. DD S60 with a Allison B500.
TomC
Hero Member
*****
Offline Offline

Posts: 6899





Ignore
« Reply #6 on: February 16, 2014, 06:33:35 AM »

Check with the big rig truck dealerships. I know we have new size 31's for $85.00. We sell boat loads of them. Good Luck, TomC
Logged

Tom & Donna Christman. '77 AMGeneral 10240B; 8V-71TATAIC V730.
Jriddle
Hero Member
*****
Offline Offline

Posts: 676





Ignore
« Reply #7 on: February 16, 2014, 06:50:25 AM »

Engine started up with one 8-D and a group 24. I haven't started this bus since June. I just let it crank a few turns then let is set for 30 seconds and had to do that twice then bus fired right up. It took a minute to smooth out but was running. Plan trip later this week.
Thanks
John
Logged

If It Can't Be Grown Then It Has To Be Mined
John Riddle
Wells NV
1984 MC9
gus
Hero Member
*****
Offline Offline

Posts: 3541





Ignore
« Reply #8 on: February 16, 2014, 04:22:41 PM »

Good point, I have a hard time wrapping my mind around 24v systems which are a real pain. Thankfully I only have one of those now.

The 24 won't take too much of that!
Logged

PD4107-152
PD4104-1274
Ash Flat, AR
luvrbus
Hero Member
*****
Offline Offline

Posts: 12908




Ignore
« Reply #9 on: February 17, 2014, 05:30:06 AM »

Most older buses used the 2 -8D for amps because of the battery placement with 80 ft of cable not for the load the 50D alternators had no problem handling the load

 Eagle had the same load as others with a 12v system and used 3-31 batteries with short cables the batteries were close to the engine compartment not up front like a MCI and GM 

I think the load deal is a tale that started on one of the boards JMO
Logged

Life is short drink the good wine first
Jriddle
Hero Member
*****
Offline Offline

Posts: 676





Ignore
« Reply #10 on: February 17, 2014, 07:44:30 AM »

I think the load deal is a tale that started on one of the boards JMO

I'm sure the bus would have started with two group 24 batteries. When this bus was in service and different kinds of drivers it would pay the operators to have a large power supply for the driver that would continue cranking. Both of my buses start on very little cranking. I'm sure with the use I give my bus the smaller batteries would be fine.

John  
« Last Edit: February 17, 2014, 07:54:34 AM by Jriddle » Logged

If It Can't Be Grown Then It Has To Be Mined
John Riddle
Wells NV
1984 MC9
gus
Hero Member
*****
Offline Offline

Posts: 3541





Ignore
« Reply #11 on: February 17, 2014, 02:36:49 PM »

Both my GM battery comps are at the rear so I assume the other GMs are also?
Logged

PD4107-152
PD4104-1274
Ash Flat, AR
Lin
Hero Member
*****
Offline Offline

Posts: 4584

1965 MC-5a




Ignore
« Reply #12 on: February 17, 2014, 04:47:53 PM »

Clifford, I can only speculate on why they did it the way they did.  It has been said that they used the two 8d's as backup power for AC, heat, etc. while idling.  Now, that could make sense since they could not shut the bus down and turn that stuff off while full of passengers.  Of course, if they put it on fast idle, I would think that there would have been enough power from the alternator.  As my 5a starts just fine with two 31's, it has nothing to do with starting.  It would seem that they were putting in a nice safety factor, which would make sense to me.  You mentioned that the Eagles had three 31's.  That amounts to an 8d and a half. My guess (only a guess) is that they just put in less of a safety factor.
Logged

You don't have to believe everything you think.
luvrbus
Hero Member
*****
Offline Offline

Posts: 12908




Ignore
« Reply #13 on: February 18, 2014, 02:29:36 PM »

I think it was because the buses were all over the country not just in one area the 42 delco starter will draw a lot of amps under a load cranking a cold engine with out a block heater most buses did not have back in the day

The HVAC motors on a 24 v system will only draw 1/2 of what a 12 v system draws ,no ac or heat with out the engine running anyway so there is not need for reserve the 50D will handle the load IMO 
Logged

Life is short drink the good wine first
Lin
Hero Member
*****
Offline Offline

Posts: 4584

1965 MC-5a




Ignore
« Reply #14 on: February 18, 2014, 03:59:12 PM »

Hey Clifford, did you get my PM?
Logged

You don't have to believe everything you think.
gus
Hero Member
*****
Offline Offline

Posts: 3541





Ignore
« Reply #15 on: February 18, 2014, 04:09:01 PM »

As Lin says, the big batts were there to support the AC/heat for the GMs huge blower motor. Up through the 4104 there was a separate engine for the AC compressor but that blower still had to be powered.

The amount of power (watts) used by bus systems is the same regardless of voltage, just simple math. Higher voltage allows the use of smaller wires but the power used is the same.
Logged

PD4107-152
PD4104-1274
Ash Flat, AR
luvrbus
Hero Member
*****
Offline Offline

Posts: 12908




Ignore
« Reply #16 on: February 19, 2014, 09:17:42 AM »

I got Lin that sucks Shocked ,Gus if your theory is right isn't a starter a motor ? I don't where the watts came from but a Delco 42 starter can draw up to 1650 amps @10.40 hp the same Delco 42 in a 24 V can draw up to 800 amps@ the same 10.40 hp go figure I just don't buy into the HVAC is the reason for more battery JMO but I have been wrong before
Logged

Life is short drink the good wine first
Jriddle
Hero Member
*****
Offline Offline

Posts: 676





Ignore
« Reply #17 on: February 21, 2014, 07:08:38 AM »

We made the trip with very little problems. One thing that happened halfway through the trip is the Not Gen light came on. The light started to come on intermittently and eventually stayed on. It did become intermittent again at the end of the trip for a short period of time. I could hear a clicking sound from under the floor. My gage never came off 28 Volts. I had no problems with the head lights. I really donít need to fix this problem on this bus but thought it would be good to do some research in case it happens on the other bus and may be good for others to learn. The only thing I didnít have working was the coach heat. It got a little cold heading north into Montana. I did some trouble shooting but decided that I needed to get going and put on a heavier coat. Any thoughts on this would be good. The bus is a 1980 MC-9.

John
« Last Edit: February 21, 2014, 07:44:53 AM by Jriddle » Logged

If It Can't Be Grown Then It Has To Be Mined
John Riddle
Wells NV
1984 MC9
Jnbroadbent
Full Member
***
Offline Offline

Posts: 100




Ignore
« Reply #18 on: February 21, 2014, 07:54:37 AM »

We made the trip with very little problems. One thing that happened halfway through the trip is the Not Gen light came on. The light started to come on intermittently and eventually stayed on. It did become intermittent again at the end of the trip for a short period of time. I could hear a clicking sound from under the floor. My gage never came off 28 Volts. I had no problems with the head lights. I really donít need to fix this problem on this bus but thought it would be good to do some research in case it happens on the other bus and may be good for others to learn. The only thing I didnít have working was the coach heat. It got a little cold heading north into Montana. I did some trouble shooting but decided that I needed to get going and put on a heavier coat. Any thoughts on this would be good. The bus is a 1980 MC-9.

John

Doesn't the Not Gen light come on when there's zero load? Don't trust the gauge, pull out the multimeter and check.
Logged

Jon
1980 Mc9 w/ veg oil
8v71
Jacksonville Fl
TomC
Hero Member
*****
Offline Offline

Posts: 6899





Ignore
« Reply #19 on: February 21, 2014, 08:51:51 AM »

Unless my alternator (50DN) has a load on it, the No Charge light will come on. I found when the batteries are charged, the light will come on. Hence I run down the road with my headlights and clearance lights on. It keeps the warning light from coming on and it is just safer to have lights on all the time. Good Luck, TomC
Logged

Tom & Donna Christman. '77 AMGeneral 10240B; 8V-71TATAIC V730.
Ed Hackenbruch
Hero Member
*****
Offline Offline

Posts: 2447




Ignore
« Reply #20 on: February 21, 2014, 12:42:55 PM »

I usually run with my headlights on for the same two reasons as Tom, but if i know that i am getting close to a stopping point for the nite i try to remember to shut them off for about the last 1/2 hour, (i try not to run after dark), to make sure that the batteries have a full charge for starting the next time.
Logged

1968 MCI 5A with 8V71 and Allison MT644 transmission.  Western USA
Jriddle
Hero Member
*****
Offline Offline

Posts: 676





Ignore
« Reply #21 on: February 21, 2014, 02:05:55 PM »

When I turned on the heater motor the gauge fluctuated. The heater motor would not come on until the Not Gen light was off. When the Not Gen light flickered that is when the volt gauge fluctuated with heater motor on and I could hear a noise under the floor. What about Air pressure switch?
Logged

If It Can't Be Grown Then It Has To Be Mined
John Riddle
Wells NV
1984 MC9
gus
Hero Member
*****
Offline Offline

Posts: 3541





Ignore
« Reply #22 on: February 21, 2014, 04:55:19 PM »

Watts is amps x volts. 746 watts = one HP. and etc. I'm just saying how it works, I didn't design it! This problem doesn't happen with a 100-150 amp truck alt conversion.

A starter motor operates two seconds or less, an AC/heat motor operates hours and hours.

Tom, Ed and Jr - as I said the load is too little and it shuts down many times a minute. My switch didn't stop that but it stopped the AC/H solenoid from clicking itself to death!!

What is the noise specifically? I'm not familiar with MC9 layout so your AC/H solenoid may be under the floor. I'm not sure what an air press switch has to do with this setup but then MCs and GMs are definitely different!!

This is all about a grossly over capacity alt trying to stabilize with our light loads.
Logged

PD4107-152
PD4104-1274
Ash Flat, AR
Jriddle
Hero Member
*****
Offline Offline

Posts: 676





Ignore
« Reply #23 on: February 22, 2014, 07:01:27 AM »

Thanks Gus

After reading this and looking at two or three recent threads we may all have the same problems. My converted bus had some clicking noise that I could never figure out. It probably all boils down to this A/C heat solenoid. My converted bus never has the Not Gen Light on. I might have to check the bulb. LOL I believe on the MCI the air pressure needs to be above 100 PSI to have the heat or A/C to work.

John
Logged

If It Can't Be Grown Then It Has To Be Mined
John Riddle
Wells NV
1984 MC9
luvrbus
Hero Member
*****
Offline Offline

Posts: 12908




Ignore
« Reply #24 on: February 22, 2014, 09:29:44 AM »

You guys ever look at the DD manual the alternator and voltage regulator rebuilding it shows the 50D for all applications,the OEM of the bus screwed the charging system up IMO 
Logged

Life is short drink the good wine first
gus
Hero Member
*****
Offline Offline

Posts: 3541





Ignore
« Reply #25 on: February 22, 2014, 05:15:37 PM »

The system was fine for its intended purpose, it was never intended for our light loads.

As I said, the AC/H solenoid switch solves the clicking problem, but not what goes on between the alt and reg.

It would seem to me that this constant on/off would overwork both the alt and VR, but maybe not?

My 4104 was converted to a standard 105 amp truck alt and had none of these problems.
Logged

PD4107-152
PD4104-1274
Ash Flat, AR
Pages: 1 2 [All]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.18 | SMF © 2013, Simple Machines Valid XHTML 1.0! Valid CSS!