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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: dougyes on November 26, 2010, 02:38:17 PM

Title: Tank weight limits
Post by: dougyes on November 26, 2010, 02:38:17 PM
I want to put 200 gal of fresh and 200 gal of grey in a 102 DL3. Will there be a weight problem? Will the floor hold up? Should I stick one in the front bay and one in the back bay to spread the load?
Title: Re: Tank weight limits
Post by: robertglines1 on November 26, 2010, 03:01:37 PM
Don't see a problem seems greyhound shipped replacement engines in them at one time..as so I'm told. also hauled freight in them..
Title: Re: Tank weight limits
Post by: PP on November 26, 2010, 03:36:42 PM
Hi Doug, I don't believe the weight will be a problem, but what are the odds that both will be full at the same time? Will
Title: Re: Tank weight limits
Post by: gus on November 26, 2010, 11:28:07 PM
It always seemed logical to me to put water tanks as close to the front as possible because the heavy engine is in the rear.
Title: Re: Tank weight limits
Post by: RJ on November 26, 2010, 11:46:30 PM
Quote from: robertglines1 on November 26, 2010, 03:01:37 PM
Don't see a problem, seems Greyhound shipped replacement engines in them at one time... so I'm told.  Also hauled freight in them...


Bob -

Greyhound shipped 8V71s on pallets in the baggage bins of the Scenicruisers & the 4107s only.  None of the other coaches used in their fleet had/have baggage bins tall enough to accommodate these engines.  And yes, freight & luggage was stuffed in the bays around the Detroits, too!

As lousy as 'Hound's maintenance is today, I suspect they just scrap the whole bus if they lose an engine. . . or sell them to an unwitting wannabe busnut!


Quote from: dougyes on November 26, 2010, 02:38:17 PM
I want to put 200 gal of fresh and 200 gal of grey in a 102 DL3. Will there be a weight problem? Will the floor hold up? Should I stick one in the front bay and one in the back bay to spread the load?

Doug -

Why so much??  Large family? 

If you're going to carry that much, you do need to think about axle loadings, front and rear.  (Are you aware that MCI had to move the HVAC unit back on the DL models in order to avoid overloading the front axle?)

[(L x W x H)/231] x 7.5 = #gallons.  Multiply that x 8 to get the # of lbs. you'd be carrying.  (L, W & H in inches)

All that weight will affect your fuel mileage, but the chassis won't mind.

Most converters place their tanks as close as possible to the house systems above in order to minimize plumbing runs.

FWIW & HTH. . .

;)
Title: Re: Tank weight limits
Post by: pipopak on November 27, 2010, 03:11:28 AM
Seems to me like a lot of water, I'm planning something around 100 cal. Also you will have only one tank full, the other will be empty.
Title: Re: Tank weight limits
Post by: jjrbus on November 27, 2010, 04:44:39 AM
I've left area's that had water but no dump with a full freshwater and black/grey tank. JIm
Title: Re: Tank weight limits
Post by: Joe Camper on November 27, 2010, 05:11:15 AM
On our bus at 41000 lb weather or not we have the fresh tank  full or empty is such an insignificant difference in fuel millage it is unmeasurable.

I barley see a difference with my 1/2 ton PU in tow.

We have an 8-V 92 TA it gets poor millage regardless I estimate 5 and so conditions dictate speed.

I have the bus verses a fleetwood so I do not have to concern myself with those things.

I too am installing an additional 100 gal fresh capacity upping it to 225.

I have 1 holding tank and it is 125 and I put in a gray bypass so with 250 fresh and 125 for poop we almost never need to take on water we are unsure and unfamiliar with.

We are spoiled with great city water here in Chicago and these reasons were contributing factors for additional capacity
Title: Re: Tank weight limits
Post by: Ed Hackenbruch on November 27, 2010, 07:23:42 AM
Water is 8.4 lbs per gallon.
Title: Re: Tank weight limits
Post by: thomasinnv on November 27, 2010, 09:04:07 AM
I remember when i was considering weight amounts for the individual bays on my 8 someone had posted cargo capacities for the individual bays, but i can't seem to find it now.  The rear most bay had the highest capacity at over 2000#, the middle bay was somewhere just over 1000 and the forward most bay was somewhere around 1500#.  Again, just going off memory so don't hold me to it but it is somewhere close.  Of course your's is a different model and will have different capacities, so I'm not sure why I even posted this.  lol.
Title: Re: Tank weight limits
Post by: Joe Camper on November 27, 2010, 03:59:40 PM
We have a Prevost.

This is all in our second bay back all the way across

A 4 cyl liquid cooled kabota diesel gen with radiator and cooling blower 1500lb approx. A 90 gal factory aux fuel tank (full) 800lb  A condensing unit for a cruisair 75 lb.  2 2500 watt Heart inverter 150lb, and a Norcold a/c d/c basement freezer (full) 100lb. 2 good size tool boxes 100lb. (this entirly fills this bay ;D)

2725lb

On ours the builder figured out he was limited to the size of the compartment more so than the limitations on weight in the plumbing bay.

If you want a hot water heater in that bay along with all the other normal things that goes in there you can figure all the remaining space for tank and it will not be too heavy.

We have 125 fresh and 125 holding and those tanks go top to bottom front to back and they staggered them in there for good distribution one tank has the hot water heater next to it and the other tank has the webosto next to it on the other side thou. That fills that bay.

I know there are professionally converted H3 45s out there with fresh tanks north of 150 gal on them.

Some of the XL!! and H3 45 have 300 gal fuel tanks



Title: Re: Tank weight limits
Post by: Bill B /bus on November 27, 2010, 04:30:04 PM
We run 125gal  fresh and 125gal  waste  tanks. That is a week supply give or take a bit.  At 200 gal each you are adding 1200 lbs to your load. And yes 8 lb/gal for fresh water and 8.4 for salt. Easier to round to 8 lb/gal unless the weight is critical then measure the specific gravity and adjust the volume to mass ratio for accuracy.
Last bay for the tankage. Highest capacity and closest to the highest capacity axle and tag. Front axle will be near to capacity with the conversion.

Our rear bay has both 125gal tanks, Webasto heater, 11gal hot water heater, 50gal aux fuel tank for Webasto and generator, macerator, water hoses and dump hoses. I only fill the fresh water tank after the waste tank is emptied. Reason is the dummy who designed the tank didn't put in a level column.  ::)  So I know that a half full fresh means a half full waste tank.

Unless I had a really good , sound reason then IMHO 200gal is way too much.

Bill
Title: Re: Tank weight limits
Post by: Len Silva on November 27, 2010, 05:31:36 PM
My opinion is to put in the biggest tanks you can fit in the available space.  Just because you have a 200 gallon tank doesn't mean you will always be driving around with that much weight.  I have large tanks but rarely carry more than a quarter tank of water unless we know we are going to dry camp for a while.  Then the capacity is nice to have.

The most important thing for us is large waste tanks as we often camp in state parks where we have water hookups but no sewer.
Title: Re: Tank weight limits
Post by: Ed Hackenbruch on November 28, 2010, 06:05:59 AM
Bill, where i come from 8x400 is 3200, not 1200. ;D
Title: Re: Tank weight limits
Post by: rv_safetyman on November 28, 2010, 07:08:39 AM
Gus, I am not sure that I would want to put as much as 3200 pounds for the two tanks in the front bay.  Doug's bus should have a tag and that should be able to help support the load.  Most of the large bus front axles are rated at 12K pounds.  It is fairly easy to overload that axle if you are not careful.

Doug, like others, I have not found a need for that much water or gray.  As has been pointed out, you don't have to use all that capacity, yet you will have it available for your special needs.  If, in the unlikely situation you load both tanks, you will have over 3200 pounds (not sure how you are dealing with black water).  I suspect that if the bay structure has not been compromised by corrosion, they can handle that load.

Jim
Title: Re: Tank weight limits
Post by: happycamperbrat on November 28, 2010, 07:14:20 AM
If you do choose to size down as others have suggested, my thoughts are to keep the fresh water tank as large as you can. THen downsize the others. The reason being that if times get really, really bad (emergency national or world crisis stuff)..... fresh water will be more important and possibly (depending on where you live) harder to come by then a place to dump.
Title: Re: Tank weight limits
Post by: Ed Hackenbruch on November 28, 2010, 09:32:59 AM
Ok, so Bob's comment about fresh water weighing 8lbs. per gallon and salt water weighing 8.4 per gallon got me to thinking as i have always seen fresh listed as around 8.4  :) So of course i had to google it to find out.  Turns out there are some variables  like temperature involved, but what it boils, (pun intended  ;D) down to is that fresh weighs around 8.34 and most people just round that off to 8.4 when figuring. Salt water also has variables in the amount of salt in the water but the accepted figure is 8.55 lbs per gallon.  Now at 8.34 lbs per gallon, 400 gallons will be 3336 lbs instead of the figure of 3200 that we came up with using 8 lbs. per gallon. Not a big difference on a bus but if you are trying to keep your weight down and your fuel mileage up, it is something to consider.  When we travel we always dump our black tank and if we are going to go to an area where i know the water is good i carry about 1/4-1/2 tank of fresh, depending on how many days it will take us to get there, and as a precaution against breaking down and being stuck somewhere for a few days. If we are going to an area where i know the water is bad i will fill the tank.
Title: Re: Tank weight limits
Post by: Dave5Cs on November 28, 2010, 10:42:19 AM
Ok Novice question.

How do you know the water condition. Is there a list somewhere or should there be, Or is it just because you have had a bad experience in that area before?

Dave
Title: Re: Tank weight limits
Post by: dougyes on November 28, 2010, 10:44:41 AM
Thank you all for your input!
Title: Re: Tank weight limits
Post by: Melbo on November 28, 2010, 11:06:41 AM
Isn't a cubic foot of water 1728 cu in not 231 ???

Just checking the math

Melbo
Title: Re: Tank weight limits
Post by: Ed Hackenbruch on November 28, 2010, 12:32:15 PM
No list Dave, i know from being there....ie,  western Wa. and Or. usually have good water.  Az. has a lot of calcium. Some states have a lot of iron or sulpher or other minerals in their water.  Of course that is where filters come in. ;D
Title: Re: Tank weight limits
Post by: Dave5Cs on November 28, 2010, 01:03:22 PM
Thanks Ed;

I thought maybe I missed the Memo!

Dave
Title: Re: Tank weight limits
Post by: RJ on November 29, 2010, 01:21:29 AM
Melbo -

There are 231 cubic inches in a gallon of liquid.  For quick computation, I rounded the weight of a gallon of water off to simply 8 lbs.

I probably should have written out the formula like this (remember L, W & H are in inches):


L x W x H = Gallons
    231


Does that help?

;)
Title: Re: Tank weight limits
Post by: happycamperbrat on November 29, 2010, 01:50:59 AM
Out here (Death Valley areaish) we have ARSENIC in our water! And they have it at least as far as New Cuyama. Just within the last couple weeks it was on the news in Barstow to not drink the water. We get printed warnings from the water company that ARSENIC is above the allowed levels of California here  :o :o :o
Title: Re: Tank weight limits
Post by: belfert on November 29, 2010, 05:31:46 PM
Arsenic is in Nevada too.  We never drink out of the water tank in the bus.  We bring bottled water.  It is usually hot most of our trips and we find we take in more water if we have bottles of water readily available.  I don't like the waste, but better than getting sick from the heat.  (I don't use bottled water at home.)

My biggest issue with water has been the combined waste tank.  It fills up faster than the fresh water tank empties.  Both the wastewater and fresh water tanks are the same size.
Title: Re: Tank weight limits
Post by: Melbo on November 29, 2010, 07:47:00 PM
Thank you RJ

That clears it up -- I was doing math and felt like a Marooon

So I went to google and found different numbers

I see now what you were posting

Melbo