CNG conversion
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Polar Bear
Is it supposed to sound like that?
If they can sell a filler for $500, I can rig a junk yard filler for $75!
Rig-a-junk yard-filler.
These are all words that you do not want to overhear your immediate neighbor using in the same sentence as Compressed Natural Gas...lol
You sir, are a filthy hillbilly, and my hat's off to you B-)
CNG coversion is a safe way and it also helps in environment safety as well cutting down the fuel cost. I vote for it.
______________________
Buy CNG Cylinders online
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Buy CNG Cylinders online
For what it's worth New Zealand has been running CNG for many many years as well as LPG and you might find some info from one of their sites. The problem with valve recession here with LPG in the land downunder is caused by the much higher combustion temps with the constant pounding of the valve being hammered into the head. Fix is a simple and does not cost much to add oil lubricant like Morey's. And of course adjusting every 20 thousand kms.(whoops 12000 miles) Most of the CNG here is for fleet buses trucks forklifts with LPG mainly on private vehicles. I have injected LPG on an LS1 engine (not in a cruiser) that makes more power on LPG (230 RWKW) and have been running this for at least 8 years.
Sorry if I went off topic a bit cheers
Sorry if I went off topic a bit cheers
Polar Bear
Is it supposed to sound like that?
For what it's worth New Zealand has been running CNG for many many years as well as LPG and you might find some info from one of their sites. The problem with valve recession here with LPG in the land downunder is caused by the much higher combustion temps with the constant pounding of the valve being hammered into the head. Fix is a simple and does not cost much to add oil lubricant like Morey's. And of course adjusting every 20 thousand kms.(whoops 12000 miles) Most of the CNG here is for fleet buses trucks forklifts with LPG mainly on private vehicles. I have injected LPG on an LS1 engine (not in a cruiser) that makes more power on LPG (230 RWKW) and have been running this for at least 8 years.
Sorry if I went off topic a bit cheers
What is the burn rate of the Moreys oil? How often do you refill it, and how much is used? Is the valve recession a common issue with CNG as well as LPG?
Just trying to get an idea of what the true fuel economy numbers would look like once the oil injection is factored in.
Years ago valve seats were lubed by tetraethyl lead in the gas. That's why older (antique) vehicles that are run a lot need hardened valve seats installed (converted) . When gas went no/low lead 40 years ago they hardened the valve seats at the factory. Unlead has something that's supposed to help and it's obviously not a problem with newer vehicles-when's the last time you heard of leaking or burned valves-used to be common to get valves ground (and seats). Doubt oil injection is needed in new vehicles with cng. Maybe used to be slight concern 20 years ago on cng.
Polar Bear
Is it supposed to sound like that?
I'm aware of the case hardening that valve seats undergo and the whole leaded gas issue. My question applies to these guys running LPG that are injecting oil currently in rigs they drive every day. Not 20 years ago. Valve recession is an ongoing issue.
It's about whether or not CNG burns with as much energy as propane does. His propane powered LS motor seems to indicate that propane might be hotter, but it was bricat's insight I was requesting.
I don't use the oil additive but as far as costings go it is minimal. See here (400 mil for 4000 kms) http://www.flashlube.com/products/electronic-valve-saver-kit.html. I don't have personal knowledge of CNG as we generally use LPG in our vehicles. A quick google search showed natural gas burns just as hot as LPG so looking after the valves would be just as helpful in this situation. I also run a 4cyl Ford van on LPG with 200,000 kms on the clock. Vehicles that are well maintained and serviced regulary will last. Hope this helps. cheers Brian
Polar Bear
Is it supposed to sound like that?
Thanks Brian, this was exactly the information that I was looking for!
Polar Bear
Is it supposed to sound like that?
So the the operating cost break down:
Every 4000km (2680 miles) the system injects 400ml (12.8 fluid oz) of oil. The oil costs US$2.69 for 50ml (1.6oz) on Amazon, giving it a cost of $21.52 every 2680 miles. So pretty much count on adding an extra $25 bucks every time you change your oil. The additive cost is not bad at all. Looks like the purchase price for the oil injection kit is $195.
http://www.cngglobal.com/product/flashlube-electronic-valve-saver-kit/
I'd have to do oil analysis before extending my oil change intervals, but from what I've heard the CNG powered engines contaminate their engine oil at a far slower rate than a gasoline counterpart. If you could push out the oil change interval to 6000 miles, the added cost of the flashlube would be a wash, possibly even a net savings if the interval were long enough (not to mention the fuel costs 1/3rd that of gasoline). I've heard of Amsoil using double filters and going 15k between changes on a gasoline motor. Wonder what you could do using CNG?
It sounds like the valves will need adjusting every 12,000 miles with this fuel setup, so someone considering this conversion should factor that in. Either get handy with your set of feeler gauges, or expect to visit your local mechanic once a year for a valve adjustment.
Other costs to be considered in the long term are the tanks themselves. Every pressurized tank needs to be pressure tested and go through recertification every so many years. If you save money and buy used tanks, you may be purchasing tanks again fairly soon if they are near the end of their certified period. A filling site that has trained staff will not fill a tank that is outside of its cert date. Building a home fill station would circumvent this, but inspection every so often would prevent one of these in the event of a traffic accident:
https://www.youtube.com/watch?v=UM0jtD_OWLU&feature=youtube_gdata_player
My co-worker who used to be a locomotive engineer showed me that video. Definitely an eye opener and one which encourages proper inspection and maintenance of these tanks, as CNG tanks are pressurized far higher than the propane tank example in the video (CNG tank wall compromise equals bigger fireball, stronger concussion wave, tank fragments fly even faster). I definitely would not mess around with a rusty tank or old valves.
I need to figure out the initial installation costs. That way the cost break out can be determined to see how long it will take to recoup the conversion expense, including the ongoing costs (flashlube, periodic tank replacement, annual valve adjustment, etc).
Edit: just found this kit- don't know anything about it or how well it works, but it looks like the 6 cylinder model kit costs $649 for the kit, minus the tanks and install. They sell used tanks too (some beyond their certification date) from the look of it. I'm not sure which tank(s) we would need for our cruisers.
http://www.cngglobal.com/product/millennium-cng-conversion-system/
Every 4000km (2680 miles) the system injects 400ml (12.8 fluid oz) of oil. The oil costs US$2.69 for 50ml (1.6oz) on Amazon, giving it a cost of $21.52 every 2680 miles. So pretty much count on adding an extra $25 bucks every time you change your oil. The additive cost is not bad at all. Looks like the purchase price for the oil injection kit is $195.
http://www.cngglobal.com/product/flashlube-electronic-valve-saver-kit/
I'd have to do oil analysis before extending my oil change intervals, but from what I've heard the CNG powered engines contaminate their engine oil at a far slower rate than a gasoline counterpart. If you could push out the oil change interval to 6000 miles, the added cost of the flashlube would be a wash, possibly even a net savings if the interval were long enough (not to mention the fuel costs 1/3rd that of gasoline). I've heard of Amsoil using double filters and going 15k between changes on a gasoline motor. Wonder what you could do using CNG?
It sounds like the valves will need adjusting every 12,000 miles with this fuel setup, so someone considering this conversion should factor that in. Either get handy with your set of feeler gauges, or expect to visit your local mechanic once a year for a valve adjustment.
Other costs to be considered in the long term are the tanks themselves. Every pressurized tank needs to be pressure tested and go through recertification every so many years. If you save money and buy used tanks, you may be purchasing tanks again fairly soon if they are near the end of their certified period. A filling site that has trained staff will not fill a tank that is outside of its cert date. Building a home fill station would circumvent this, but inspection every so often would prevent one of these in the event of a traffic accident:
https://www.youtube.com/watch?v=UM0jtD_OWLU&feature=youtube_gdata_player
My co-worker who used to be a locomotive engineer showed me that video. Definitely an eye opener and one which encourages proper inspection and maintenance of these tanks, as CNG tanks are pressurized far higher than the propane tank example in the video (CNG tank wall compromise equals bigger fireball, stronger concussion wave, tank fragments fly even faster). I definitely would not mess around with a rusty tank or old valves.
I need to figure out the initial installation costs. That way the cost break out can be determined to see how long it will take to recoup the conversion expense, including the ongoing costs (flashlube, periodic tank replacement, annual valve adjustment, etc).
Edit: just found this kit- don't know anything about it or how well it works, but it looks like the 6 cylinder model kit costs $649 for the kit, minus the tanks and install. They sell used tanks too (some beyond their certification date) from the look of it. I'm not sure which tank(s) we would need for our cruisers.
http://www.cngglobal.com/product/millennium-cng-conversion-system/
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Just to add about oil. My LPG oil is as clean as a whistle after 6000 miles. That is visual only and viscosity appears to be OK. (My technical testing consists of rubbing the oil between two fingers so it is not technical specs)
Tank testing is done here every 10 years and costs $100.00 to get it certified. Add cost of R/R if not handy with spanners. I doubt whether any checks would be done on tank certification unless you have an annual roadworthy inspection. Over here if you sell your car with a roadworthy that would form part of the checks. I am sure there are 100's if not 1000's of vehicles travelling around my country with out of date tanks. They are over engineered but other than rust it is more likely the valves in the tanks that deteriate
Over here purchase and installation is about $5000.00 so it is not cheap. We had government cash back to help with this ($2000.00) but this incentive has now been withdrawn or cut back.
This is for a LPG liquid injection system as opposed to LPG gas injection system. Newer vehicles are required to have LPG liquid injection.
LPG costs us about 70 cents per litre. Petrol(gas to you) costs $1.40 per litre. LPG uses about 20% more. So LPG @ 70 cents plus 20% = 84 cents per litre. Does not take long to get your money back.
I have hydrolic lifters in the LS1 so have not done valve adjustment. cheers Brian
Tank testing is done here every 10 years and costs $100.00 to get it certified. Add cost of R/R if not handy with spanners. I doubt whether any checks would be done on tank certification unless you have an annual roadworthy inspection. Over here if you sell your car with a roadworthy that would form part of the checks. I am sure there are 100's if not 1000's of vehicles travelling around my country with out of date tanks. They are over engineered but other than rust it is more likely the valves in the tanks that deteriate
Over here purchase and installation is about $5000.00 so it is not cheap. We had government cash back to help with this ($2000.00) but this incentive has now been withdrawn or cut back.
This is for a LPG liquid injection system as opposed to LPG gas injection system. Newer vehicles are required to have LPG liquid injection.
LPG costs us about 70 cents per litre. Petrol(gas to you) costs $1.40 per litre. LPG uses about 20% more. So LPG @ 70 cents plus 20% = 84 cents per litre. Does not take long to get your money back.
I have hydrolic lifters in the LS1 so have not done valve adjustment. cheers Brian
Polar Bear
Is it supposed to sound like that?
Thanks Brian, your oil observations confirm what I've been hearing from mechanics- 10,000 miles between oil changes with a quality synthetic is not unrealistic. They just advise doing periodic oil analysis at first to verify that the additive package is holding up. Apparently the additives will burn off in the oil long before contamination becomes an issue with LPG/CNG motors (and that's usually well past 10K).
The tanks I'm finding for sale are pretty spendy if you want the lightweight (type 4) ones- $3600 for a 10 gallon tank. The type 1 steel tanks are the heaviest, but a pair of new 8 Gasoline Gallon Equivalent (GGE) type 1 tanks will run $1600 and should fit (haven't measured yet to verify) where the spare tire goes. That would get you approximately 150 miles of range between fill ups.
Those two tanks would add nearly 400 pounds of weight to the rear (before fuel), so plan on upgrading your rear springs. Just think of the weight as carrying a couple of your larger buddies around with you everywhere the truck goes. LPG tanks cost and weigh significantly less.
Info I'm seeing online says a certified installer converting your vehicle to LPG/CNG will charge somewhere between 3 and 5 thousand dollars in labor.
Retail prices locally right now for CNG and LPG are both right around $2.10/gallon and are within 10 cents per gallon of each other. Home prices with a filling station installed would be considerably lower I would imagine, you just have the added expense of the initial purchase for the compressor filling kit.
Looks like it's down to a waiting game for those two companies to bring their CNG home filling stations to market for $500. I think only then would this conversion start to pay for itself within two or three years. Otherwise you're looking at 10+ years to break even.
Mike
The tanks I'm finding for sale are pretty spendy if you want the lightweight (type 4) ones- $3600 for a 10 gallon tank. The type 1 steel tanks are the heaviest, but a pair of new 8 Gasoline Gallon Equivalent (GGE) type 1 tanks will run $1600 and should fit (haven't measured yet to verify) where the spare tire goes. That would get you approximately 150 miles of range between fill ups.
Those two tanks would add nearly 400 pounds of weight to the rear (before fuel), so plan on upgrading your rear springs. Just think of the weight as carrying a couple of your larger buddies around with you everywhere the truck goes. LPG tanks cost and weigh significantly less.
Info I'm seeing online says a certified installer converting your vehicle to LPG/CNG will charge somewhere between 3 and 5 thousand dollars in labor.
Retail prices locally right now for CNG and LPG are both right around $2.10/gallon and are within 10 cents per gallon of each other. Home prices with a filling station installed would be considerably lower I would imagine, you just have the added expense of the initial purchase for the compressor filling kit.
Looks like it's down to a waiting game for those two companies to bring their CNG home filling stations to market for $500. I think only then would this conversion start to pay for itself within two or three years. Otherwise you're looking at 10+ years to break even.
Mike
Home filling requires re-certification and maintenance at certain intervals. You need to add that cost.
If you like wheeling on rocks/boulders, a hole in a tank would be costly.
If you like wheeling on rocks/boulders, a hole in a tank would be costly.
Polar Bear
Is it supposed to sound like that?
After looking into what those tanks are subjected to for testing (impact, gunshot, fire, corrosive) I have a high degree of confidence in them. That being said, I'd definitely build a solid skid plate to protect them. More to protect the valves than anything else really.
Heavy valve protectors available-thick steel bolts/clamps to top of tank with access to line/handle-route the stainless lines up high away from rocks/etc. Saw video of car dropped from high crane and gunshots-no leaks/damage.
Any idea of how much an OEM sub tank full of gasoline weigts?
Polar Bear
Is it supposed to sound like that?
Fuel weighs 7 pounds per gallon. Not sure what the tank itself weighs.
