My $900 RV

[PNW_Steve]

There seems to be some confusion between CNG and LPG

Compressed Natural Gas is not the same thing as Liquefied Petroleum Gas (Propane) .

Tanks and fuel systems are very different.

CNG tanks require periodic pressure testing or replacement.

"All CNG cylinders for use in road vehicles in the U.S. must be labeled with a ‘do not use after’ date. This is a uniform federal regulation applying throughout the U.S. and is contained in Federal Motor Vehicle Safety Standard (FMVSS) 304 Compressed Natural Gas Fuel Container Integrity,” "

[Sleddgracer]

Originally Posted by Ronnie

It has been a while since I have messed with propane as a fuel for engines, but if I remember right re jetting the carb, new fuel tank and a different fuel regulator is what is needed to convert from CNG to propane.

Do the newer engines use fuel injection? I have not seen anything but a carb on a forklift. Can not imagine how you would do fuel injection with a gaseous fuel instead of liquid.

I was looking at a school bus ad today -claimed to have a 454 on propane with fuel injection

[cadillackid]

maybe it was dual fuel? propane conversion?

[Sleddgracer]

Originally Posted by cadillackid

maybe it was dual fuel? propane conversion?

it just said on propane although I have seen newer ( 2001 2002 ) buses on dual fuel - wouldn't all chevy motors have fuel injection? then set up for gas and/or propane

[PNW_Steve]

Originally Posted by Sleddgracer

it just said on propane although I have seen newer ( 2001 2002 ) buses on dual fuel - wouldn't all chevy motors have fuel injection? then set up for gas and/or propane

I have seen quite a few dual fuel setups as well as propane only setups.

The propane only ones did not have any fuel injection or carburetor for gasoline.

OP has a CNG bus. I have never seen a CNG to gasoline conversion.

If I lived in the right part of the country and wanted a vehicle for local travel I would jump on a CNG vehicle. But.. I don't.

[Native]

Originally Posted by dgorila1

Awesome price!!! What auction site did you buy it through?

Yeah, I would like to know the auction house as well ... being in the DFW area and all!

[Seriousracer]

Originally Posted by PNW_Steve

I have seen quite a few dual fuel setups as well as propane only setups.

The propane only ones did not have any fuel injection or carburetor for gasoline.

OP has a CNG bus. I have never seen a CNG to gasoline conversion.

If I lived in the right part of the country and wanted a vehicle for local travel I would jump on a CNG vehicle. But.. I don't.

This applies to cng to you can go back and forth between gas and cng. My 2016 Chevy had the dual fuel system it switche automatically to gas Fill up with cng and hit the reset button and back to cng.
Performance loss was about thirty horse power while towing. I would keep the cng and add a gas tank and the conversion system. It will pay for itself.

[musigenesis]

Originally Posted by Sleddgracer

I was looking at a school bus ad today -claimed to have a 454 on propane with fuel injection

I called up the original school system that owned my bus to get any info on maintenance records (not much but the guy I talked to actually did the engine rebuild and confirmed everything the seller had told me about it). An hour later the guy called me back and asked me if I wanted to buy a nearly-new CNG bus they had that they were giving up on (he had no idea why I had bought a school bus but was hoping I wanted more).

Could you possibly tow a big extra tank of gas for long-distance trips? If so this would also leave you well-positioned for that Mad Max future apocalypse.

[Sleddgracer]

Originally Posted by musigenesis

I called up the original school system that owned my bus to get any info on maintenance records (not much but the guy I talked to actually did the engine rebuild and confirmed everything the seller had told me about it). An hour later the guy called me back and asked me if I wanted to buy a nearly-new CNG bus they had that they were giving up on (he had no idea why I had bought a school bus but was hoping I wanted more).

Could you possibly tow a big extra tank of gas for long-distance trips? If so this would also leave you well-positioned for that Mad Max future apocalypse.

never having used CNG, I do know you can siphon propane from a bottle into a vehicle's propane tank, using a suitable hose with proper fittings - set the propane bottle higher than the vehicle's tank, connect the hose, turn the bottle upside down and open the valves - the propane will flow until pressure balances out between the tanks, so you can't fully empty the bottle, but it, hopefully, gets you to the next filling station - when traveling north 20+ years ago, I carried 2 x 20 lb bottles and a 30 lb bottle and used them quite often

[cadillackid]

Towing a tank is likely going to make you a HazMat load.. one of the commercial drivers here would know the amount of flammable gas you can carry before its hazmat. And also if there are other rules associated with having it on a trailer vs onboard. At some point it seems just easier to have a bus that uses gas, diesel, or even propane CNG just has not taken off quickly in the consumer market, so far fleets with their own fueling stations are the only big takers.

[Sleddgracer]

Originally Posted by cadillackid

Towing a tank is likely going to make you a HazMat load.. one of the commercial drivers here would know the amount of flammable gas you can carry before its hazmat. And also if there are other rules associated with having it on a trailer vs onboard. At some point it seems just easier to have a bus that uses gas, diesel, or even propane CNG just has not taken off quickly in the consumer market, so far fleets with their own fueling stations are the only big takers.

there was a bus advertised on KIJIJI for a while with dual CNG/Gas - was advertised as being converted - a sloppy conversion, moss covered bus, hadn't moved in years - the only reason I remember it was the unusual dual fuel it was set up for

[Ronnie]

I needed to move 6000 gallons of diesel, so looked up what you can haul and it was around a hundred gallons, other then the vehicle fuel tank without hazmat permits.

No idea on CNG

[CHEESE_WAGON]

Originally Posted by cadillackid

Towing a tank is likely going to make you a HazMat load.. one of the commercial drivers here would know the amount of flammable gas you can carry before its hazmat. And also if there are other rules associated with having it on a trailer vs onboard. At some point it seems just easier to have a bus that uses gas, diesel, or even propane CNG just has not taken off quickly in the consumer market, so far fleets with their own fueling stations are the only big takers.

Towing a tank doesn't make a HazMat load... Actually has nothing to do with it. HazMat endorsement is required ONLY if it is over 1,000 lbs (the minimum reportable quantity) of a qualifying material. You can tow over 1,000 lbs of water in a tank, but water is not HazMat. And if it's under 119 gallons, does not require T endorsement either. 1,000 lbs of water works out to somewhere around 125 gallons, however. IF water were actually HazMat, 119 gallons would weigh around 952 lbs, and therefore be exempt from either requirement anyway.

Originally Posted by Ronnie

I needed to move 6000 gallons of diesel, so looked up what you can haul and it was around a hundred gallons, other then the vehicle fuel tank without hazmat permits.

No idea on CNG

Ok, here's the skinny....

DOT regs state 119 gallons gaseous or liquid before a T (tank) endorsement is required. HazMat endorsement is required on reportable quantities (over 1,000 lbs) of a qualifying material. Side note, as a general rule, if a given material has a UN number in the HazMat guidebook, it's HazMat.

So, technically, under 119 gallons does not require T endorsement, and under 1,000 lbs does not require HazMat endorsement. However, factory-mounted fuel tanks directly supplying a vehicle's chassis engine are exempt, a critical sidenote, as many 18-wheelers have twin fuel tanks in excess of 80 gallons each.

But it seems to me that mounting an auxiliary tank not directly feeding the engine should be legal, so long as it does not exceed 119 gallons or 1,000 lbs of fuel. I don't see where such tank being towed on a trailer would make a difference. Over 119 gallons would also require placards on the towed tank in addition to the CDL with T endorsement, BTW. I have seen little lowbelly towable tanks on frames with tires similar to the fronts on a farm tractor, that DID, however, have HM placard signs (Anhydrous Ammonia, if memory serves). These were likely in excess of 119 gallons. Not sure.

So unless there's some other obscure rule or regulation that I'm not aware of, (not a HazMat driver, just received some basic training in knowing what qualifies), less than 119 gallons, liquid or gaseous, or less than 1,000 lbs of a qualifying hazardous material would be exempt. For example...

Diesel is lighter than water, so assume 7 lbs per gallon, as water is about 8 lbs per gallon.

6000 x 7, from previous post, would be 42,000 lbs.... WAY beyond non-reportable quantities. Definitely would require HM endorsement, and 6,000 gallons would definitely require T endorsement.

118 gallons x 7, however, would only be 826 lbs, and therefore should be exempt from either requirement.

Not knowing what a gallon of LPG or CNG weighs, I can't accurately summarize, however, I'm pretty sure that CNG at least, would be lighter than water, diesel, or gasoline. LPG, well, I'm guessing a 20 lb tank would hold about 3 gallons of water if you tried... I could be wrong on that.

One other thing (for the OP's benefit), most multi-fuel or alternate fuel vehicles have some sort of fuel system calibration unit to properly meter fuel delivery for the type of fuel being used. This means extra control boxes, relays, etc. as well as a control system calibrated for the different burn rate and optimum air-fuel ratio for a given fuel. Ethanol, for example, burns hotter and and runs richer at typical gasoline air-fuel ratios. This is why standard gasoline engines have problems burning ethanol, and also why E85 engines that are calibrated for ONLY E85 will run poorly on lower percentages of ethanol, or ethanol-free gasoline (yes, you can still buy it).

What this means is that if you wish to convert your CNG bus to gasoline, you will likely need to transplant a good bit more than fuel tanks and computers. Ford Tauruses for example, could be had in flex-fuel, which required a setup with multiple configurations and a means of the system being able to identify when a different fuel was being used. I assume no different with a CNG vehicle. Perhaps it is simply a matter of swapping such a piece for a gas-powered version, but I doubt it would that simple. I do think it would run as deep as fuel lines, injector rail assembly, possibly intake manifold, PCM / wiring harness.

[Sleddgracer]

Originally Posted by CHEESE_WAGON

Towing a tank doesn't necessarily make a HazMat load... ONLY if it is over 1,000 lbs (the minimum reportable quantity) of a qualifying material. And you can tow over 1,000 lbs of water in a tank, water is not HazMat. And if it's under 119 gallons, does not require T endorsement either.



Ok, here's the skinny....

DOT regs state 119 gallons gaseous or liquid before a T (tank) endorsement is required. HazMat endorsement is required on reportable quantities (over 1,000 lbs) of a qualifying material. Side note, as a general rule, if a given material has a UN number in the HazMat guidebook, it's HazMat.

So, technically, under 119 gallons or 1,000 lbs requires neither HazMat nor T endorsement. However, factory-mounted fuel tanks directly supplying a vehicle's chassis engine are exempt, a critical sidenote, as many 18-wheelers have twin fuel tanks in excess of 80 gallons each.

But it seems to me that mounting an auxiliary tank not directly feeding the engine would be legal, so long as it does not exceed 119 gallons or 1,000 lbs of fuel. I don't see where such tank being towed on a trailer would make a difference. Over 119 gallons would also require placards on the towed tank in addition to the CDL with T endorsement, BTW. I have seen little lowbelly towable tanks on frames with tires similar to the fronts on a farm tractor, that DID, however, have HM placard signs (Anhydrous Ammonia, if memory serves). These were likely in excess of 119 gallons. Not sure.

So unless there's some other obscure rule or regulation that I'm not aware of, (not a HazMat driver, just received some basic training in knowing what qualifies), less than 119 gallons, liquid or gaseous, or less than 1,000 lbs of a qualifying hazardous material would be exempt. For example...

Diesel is lighter than water, so assume 7 lbs per gallon, as water is about 8 lbs per gallon.

6000 x 7, from previous post, would be 42,000 lbs.... WAY beyond non-reportable quantities. Definitely would require HM endorsement, and 6,000 gallons would definitely require T endorsement.

118 gallons x 7, however, would only be 826 lbs, and therefore should be exempt from either requirement.

Not knowing what a gallon of LPG or CNG weighs, I can't accurately summarize, however.

propane flows to the ground when it leaks, CNG rises when it leaks so CNG must weigh less per gal than Propane - perhaps tanks filled with helium would lower GVW?

[Ronnie]

Originally Posted by Sleddgracer

propane flows to the ground when it leaks, CNG rises when it leaks so CNG must weigh less per gal than Propane - perhaps tanks filled with helium would lower GVW?

Yes but helium does not burn so well, engine might not run....

But hydrogen now we are talking...less weight and a good fuel.

[Sleddgracer]

Originally Posted by Ronnie

Yes but helium does not burn so well, engine might not run....

But hydrogen now we are talking...less weight and a good fuel.

and tanks designed to safely carry hydrogen without the possibility of explosion

[Sleddgracer]

Originally Posted by Ronnie

Yes but helium does not burn so well, engine might not run....

But hydrogen now we are talking...less weight and a good fuel.

sounds too good and too simple to be true

https://www.hho-1.com/?gclid=EAIaIQo...SABEgLKS_D_BwE

[Sleddgracer]

Originally Posted by Sleddgracer

sounds too good and too simple to be true

https://www.hho-1.com/?gclid=EAIaIQo...SABEgLKS_D_BwE

https://www.ballard.com/markets/transit-bus

http://zeroemissionbus.org/

[Native]

Originally Posted by Sleddgracer

sounds too good and too simple to be true

https://www.hho-1.com/?gclid=EAIaIQo...SABEgLKS_D_BwE

Does sound too good to be true. Of course, the website is a marketing tool. I did not read it all, but it does sound promising.

[Sleddgracer]

Originally Posted by Native

Does sound too good to be true. Of course, the website is a marketing tool. I did not read it all, but it does sound promising.

that's what I thought too, so I did some more research - looks like there is some science behind it and some sophisticated products available - anywhere from a 20% increase in mileage to almost double in some reports - supposed to work equally well for gas and diesel