How long does the oil stay clean in a CNG car ? I'm wondering how much the darkening of oil is derived from combustion byproducts compared to the ingestion of dirt through the air intake in gasoline powered cars.
Has anybody owned a CNG car ?
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I drove a propane powered truck. It's oil always looked new
I guess when you guys say "propane" it's what we call LPG? If so, yes, the engine oil stays clean looking for a long, long time. Worked on taxis many years ago, they all ran on LPG back then, and the engines did huge mileages with minimal maintenance. So saying "combustion is combustion" is not really correct.
What you guys are telling me leads me to suspect that most of the oil darkness on gasoline powered cars is from combustion byproducts. Propane and CNG doesn't have any combustion byproducts and therefore the oil stays clean next to forever.
CNG and LPG were big in NZ in the '80's, we have not much crude oil, but an abundance of gas. Service stations were set up to supply both gases, incentives given to convert...and I have a ticket in gas conversion (wouldn't have a clue how to these days). I had a couple of cars on it. The oil stays clean, and the problem was that people didn't change it because it still looked good. Acids built up, and leached the lead off copper/lead bearings, amongst other damage. When I converted my own Holden to CNG I changed to bearing to heavy duty. We still have oil on NZ with ''safe for CNG and LPG'' logos. I presume higher TBN.
Originally Posted By: Merkava_4
Propane and CNG doesn't have any combustion byproducts and therefore the oil stays clean next to forever.
Forever is a long time, but when we ran the taxis on LPG, the oil was still very clean after a 10,000 km OCI. Instead of chasing oils and short OCIs, Merk, you know what to do now. Get an LPG vehicle!
Some oil companies were and are intentionally making lower TBN oils for LPG and CNG engines. We never bothered with that, and all the engines went hundreds of thousands of miles.
Propane and CNG doesn't have any combustion byproducts and therefore the oil stays clean next to forever.
Forever is a long time, but when we ran the taxis on LPG, the oil was still very clean after a 10,000 km OCI. Instead of chasing oils and short OCIs, Merk, you know what to do now. Get an LPG vehicle!
Some oil companies were and are intentionally making lower TBN oils for LPG and CNG engines. We never bothered with that, and all the engines went hundreds of thousands of miles.
We ran trucks on it in the 70's. Fantastic fuel, burns ultra clean and makes almost zero emissions. Zero carbon build up and super easy starts in any weather as well.
Pull a head off a CNG motor and almost zero carbon as well. I have nothing but good memories of that stuff...
Pull a head off a CNG motor and almost zero carbon as well. I have nothing but good memories of that stuff...
When we converted the C-series diesel to run on natural gas at Cummins, we had to upgrade the valve seat materials to deal with seat wear. The dry operating environment of gaseous fuels eliminates seat lubrication that is present in liquid fuel engines.
There are dedicated natural gas engine oils that have varying levels of ash. Some natural gases contain more sulfur than others, and TBN/TAN must be monitored to ascertain the proper OCI. Just because the oil doesn't get dark doesn't mean bad things aren't or can't be happening.
There are dedicated natural gas engine oils that have varying levels of ash. Some natural gases contain more sulfur than others, and TBN/TAN must be monitored to ascertain the proper OCI. Just because the oil doesn't get dark doesn't mean bad things aren't or can't be happening.
When I was in the Navy we had Dodge passenger vans that we would use for patrols/new in-doc pickup that were CNG. They were low on power compared to gas vans but didn't ever have any issues. Always fired right up and ran smooth.
From what I recall we had the same van while I was stationed there for 3 years and I only remember it being out for service one time. Oil always looked clean, don't know if they changed it or not but I'm sure it got the cheapest bid oil the government buys.
From what I recall we had the same van while I was stationed there for 3 years and I only remember it being out for service one time. Oil always looked clean, don't know if they changed it or not but I'm sure it got the cheapest bid oil the government buys.
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We have 112 , 2000 Honda Civic GXA's here at work...the dang things wont die and go away. Aside from being small they are good cars.You are relegated to staying in town because the range is only 200 miles per tank and there is virtually nowhere to fuel up outside of town. The CNG tanks have a 15 to 20 year life span (depending on manufacturer) and after they are expired you have to replace the tank at a few thousand dollars.
Originally Posted By: InhalingBullets
We have 112 , 2000 Honda Civic GXA's here at work...the dang things wont die and go away. Aside from being small they are good cars.You are relegated to staying in town because the range is only 200 miles per tank and there is virtually nowhere to fuel up outside of town. The CNG tanks have a 15 to 20 year life span (depending on manufacturer) and after they are expired you have to replace the tank at a few thousand dollars.
The range is a good point. The vans we drove only had like a 180 mile range or something pretty small also. If you left base you better be sure you had a full tank as there were no refueling stations around besides on base. We had a few new guys run out of gas out in town, had to be towed back.
We have 112 , 2000 Honda Civic GXA's here at work...the dang things wont die and go away. Aside from being small they are good cars.You are relegated to staying in town because the range is only 200 miles per tank and there is virtually nowhere to fuel up outside of town. The CNG tanks have a 15 to 20 year life span (depending on manufacturer) and after they are expired you have to replace the tank at a few thousand dollars.
The range is a good point. The vans we drove only had like a 180 mile range or something pretty small also. If you left base you better be sure you had a full tank as there were no refueling stations around besides on base. We had a few new guys run out of gas out in town, had to be towed back.
Originally Posted By: SteveSRT8
Zero carbon build up and super easy starts in any weather as well.
LPG, of course, would have winter starting issues, unlike the natural gas. Ever try starting a propane car if it's been sitting outside unplugged and the ambient temperatures are below the boiling point of the LPG? It's not pretty.
Zero carbon build up and super easy starts in any weather as well.
LPG, of course, would have winter starting issues, unlike the natural gas. Ever try starting a propane car if it's been sitting outside unplugged and the ambient temperatures are below the boiling point of the LPG? It's not pretty.
We have lots and lots of dual fuel cars in Oz, where you can switch between petrol and LPG. In these systems, when running on LPG, the engine initially fires up using petrol, then after a few seconds, the computer switches back over to LPG. Makes cold starts a breeze, no matter the temperature...although, we obviously don't get anywhere near as cold as Canada!
Ford Falcon is available with factory LPG only (not dual fuel). It uses an injection rather than vapor system. To improve starting, the system pre-primes itself when you press the key fob to unlock the doors, or when you open the drivers door.
http://www.mynrma.com.au/motoring-services/reviews/car-reviews/ford/ford-falcon-eco-lpi.htm
Have to be careful to use the correct terminology when discussing LPG on this forum. Here, we refer to LPG as "gas", which gets confusing as you guys call petrol "gas". We speak quite different versions of the English language sometimes
Ford Falcon is available with factory LPG only (not dual fuel). It uses an injection rather than vapor system. To improve starting, the system pre-primes itself when you press the key fob to unlock the doors, or when you open the drivers door.
http://www.mynrma.com.au/motoring-services/reviews/car-reviews/ford/ford-falcon-eco-lpi.htm
Have to be careful to use the correct terminology when discussing LPG on this forum. Here, we refer to LPG as "gas", which gets confusing as you guys call petrol "gas". We speak quite different versions of the English language sometimes
Yes, we call gasses gas, and we don't call liquids gas.
We used to have dual fueled cars here, but the taxis slowly got switched to LPG only. Drivers wouldn't use the gasoline often enough, and things would get gummed up. And, this was before computers were commonplace - just a switch. LPG here is almost dead in the water, which is unfortunate. It was a tossup to convert my F-150 to a small four barrel or to LPG, with the ridiculous factory setup not working well.
I haven't seen a factory LPG vehicle here for a long time. Ford, too, had the last one here.
I haven't seen a factory LPG vehicle here for a long time. Ford, too, had the last one here.
Yes, I've pulled many sets of injectors from taxis and ultrasonically cleaned them due to gumming up from lack of use. I guess taxi drivers are the same the world over!
LPG is a really viable fuel here, and used to be about a third the price of petrol, but the federal government increases taxes on it year after year. Where I live, LPG is now only about 30% cheaper than petrol, making it less attractive than it used to be. Ford used to advertise that you could run a 4.0 LPG Falcon for the same money as a Corolla, I doubt that's the case these days though.
LPG is a really viable fuel here, and used to be about a third the price of petrol, but the federal government increases taxes on it year after year. Where I live, LPG is now only about 30% cheaper than petrol, making it less attractive than it used to be. Ford used to advertise that you could run a 4.0 LPG Falcon for the same money as a Corolla, I doubt that's the case these days though.
When we were doing the LPG, the gasoline side of things was still mostly in the carb world, so that did sort of simplify things. I'm not even sure of the retail price of propane lately; it's so rarely seen. I do know that last time I checked a couple stations had really wide swings in prices, with one being over 30% more than the other.
Here, taxi drivers were responsible for their own fuel costs, so were very hesitant to use the gasoline.
Here, taxi drivers were responsible for their own fuel costs, so were very hesitant to use the gasoline.
I used to run our HG Holden for the same cost as the Mini 1000 we had around the same time...and could carry 6 people and tow a trailer with 2 motorcycles which the Mini couldn't. Last place I worked (last year) we still had an LPG tank...although we filled more BBQ bottles than cars.
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