Auto Propane Conversion

Discussion in 'Propulsion' started by Jim Bridges, Apr 7, 2012.

  1. Jim Bridges
    Joined: Jan 2012
    Posts: 1
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Havre de Grace, MD

    Jim Bridges New Member

    For 454 or similar Mercruiser-like engines. I rarely see ads for or discussion about conversion to propane as a solution to $4 gasoline, and I wonder what the catch is. Propane is relativity inexpensive, less wearing on engines, readily avavilable, and used in most cities' mass transit systems, bussess especially, which seems to have allayed the public's fear of being blown up on the way to the ball game.

    So what IS its problem? High cost of conversion? I would appreciate hearing what you know about it and especially if you know who's doing gas to propane conversions or producing kits. Thanks.

    hdg md
  2. CDK
    Joined: Aug 2007
    Posts: 3,324
    Likes: 148, Points: 63, Legacy Rep: 1819
    Location: Adriatic sea

    CDK retired engineer

    The problem is to get your tank filled.
    You could install a fixed tank in your boat and have it filled while on the trailer, or use a number of bottles. Technically there are no issues whatsoever, the engines run like on gasoline and the conversion is simple and inexpensive.
  3. gonzo
    Joined: Aug 2002
    Posts: 15,592
    Likes: 1,094, Points: 123, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    There are in use in many enclosed places like warehouses. The danger of fuel spills makes propane a good option. When you calculate what the calorie content is in LPG per Dollar, the cost is not really cheaper.
  4. Frosty

    Frosty Previous Member

    All taxis in Bangkok are propane, the cost of LPG is miniscule in comparison to petrol.

    Most Petrol cars are converted and refil stations are ubiquitous .

    Not the same offshore I suspect.

    America seems positivly backwards in fuel economy for vehicles as heavy deisels here use something called HGV and stations are common.

    I use E 20 in petrol engines and dont give me any crap about it runs bad, I cant tell the difference between E 20 --E 85 or 91 or 95.

    Again looking for HGV stations off shore is not possible,--until---- wise up time.
  5. tom kane
    Joined: Nov 2003
    Posts: 1,767
    Likes: 48, Points: 58, Legacy Rep: 389
    Location: Hamilton.New Zealand.

    tom kane Senior Member

    The liquid injection of bottled gas to run an engine looks like the best technology but there seems to be a big fight over patent Claims slowing that development and supply down. I have tried a small version and I believe it is the safest system all round using a volatile fuel in a powerboat.
  6. tunnels

    tunnels Previous Member

    I used CNG in my older car for ages and it was 90% dedicated and just had a very small petrol tank . had to clean the spark plugs once every 2 weeks when it got a little hard to start ! i read up to understand it and used it all the time on long trips and round town was great and hard cold starts in the winter never happened !
    My father had a mobile home and had a really big Gas tank in that used for cooking and the motor ,all came off one tank plus he had made a kerosene manifold that could be used as well as ordinary petrol !! :D

    Gas in boats !! why not!! the tanks full could be lighter than diesel or petrol . just need to make up your mind and do it i guess!:confused:
  7. whitepointer23

    whitepointer23 Previous Member

    there are boats running on lpg here, i have only seen it on trailer boats where they can fill up at the service station. years ago there was a kit for outboards at the melbourne boat show.
  8. whitepointer23

    whitepointer23 Previous Member

    are you talking cng or lpg because cng is new technology here.
  9. tunnels

    tunnels Previous Member

    Jesus we had both in nz since the early 1980s could have either ! some people liked CNG and other like LPG one was a little better than the other ! I had Cng on my car But gradually the prices of the gas kept going up and up till it was getting close to the price of petrol for a user and mpg distance equivlent so why fit it any more , typical !!:D
  10. whitepointer23

    whitepointer23 Previous Member

    its all lpg here, cng is getting fitted to trucks now. you are right about gas, it is getting to expensive to justify changing over to it.
  11. tunnels

    tunnels Previous Member

    Its typical ! same as cheap imported petrol we used to get in nz long time ago didnt take long before the price was the same as every where else .
    I dont think about it any more because i dont drive here in china and get taken to work !! the buses are so cheep its crazy Like 5 cents from one side of the city to the other ,taxi are a lot more exspensive and the same trip would cost $10 dollars nz . In the university town where i live there are free buses every 15 minutes the do just the local areas .
    Last trip back to nz cost $100 just to fill up the two boat tanks and $100 to fill the car so $200 dollars just to go out for a days fishing all of a sudden fish and chips at the local shop is a really good meal and only cost $3;00 for me for dinner !! petrol 91 standard was $2;15 a liter 3 months ago in nz so do the sums and add everything its a exspensive days outing!. Lucky i only go back to nz once a year so dont really think to much about it .
    Cost of living here in china ! i Used to be able to live and eat well on 120 yuan each week now with the 2 of use costs about 4 times that amount but its still cheap living !!we eat out 4 or 5 night a week usually . food to cook at home for 3 meals about 300 yuan . :D
    Joined: Oct 2002
    Posts: 4,519
    Likes: 110, Points: 63, Legacy Rep: 1009
    Location: Conn in summers , Ortona FL in winter , with big d

    FAST FRED Senior Member

    A 20# propane bottle only has about 4 gal of fuel.

    The fuel is less powerful (tho far cleaner) so 4 gal will not go as far as 4 gal of gas.

    A 100G propane tank is HUGE .

    Figure the range desired before refilling , and how you will refill .

  13. Frosty

    Frosty Previous Member

    Over 6psi it is liquid. How many litres of gas is a litre of propane liquid?
  14. whitepointer23

    whitepointer23 Previous Member

    i think a lt of liquid propane is 270 lts of gas.

  15. thudpucker
    Joined: Jul 2007
    Posts: 885
    Likes: 31, Points: 0, Legacy Rep: 453
    Location: Al.

    thudpucker Senior Member

    I'd bet you can find the Marine re-fill stations along any route you take.
    Google it and see if they have a way of refiling your inboard tanks.

    Plus, those tanks will hold your whole boat up in case of a catastrophe at sea.
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.