Results 1 to 6 of 6

Thread: ZJ (4.0) Grand Cherokee Propane Conversion

  1. #1
    Join Date
    Jan 2009
    Location
    Kitchener, Ontario
    Posts
    9
    Time Online: 9 Hrs 1 Min 23 Secs
    Avg. Time Online: 1 Secs
    Rep Power
    9

    ZJ (4.0) Grand Cherokee Propane Conversion

    This is a little build-up about a propane conversion, that I have personally done, to my 1997 Grand Cherokee. It's a stock 4.0 litre, with a 42RE automatic transmission and 4WD. I chose to go from gasoline to straight propane, and not a dual fuel set-up. The Jeep itself was very solid and mechanically perfect. The only thing that was not so good, was the fuel mileage! Anyhow, on to the "good stuff".

    I decided to keep this project "low-buck". Therefore, many parts that I used were second hand and easily available at salvage yards.
    Note: Although "not new" parts were chosen, they would all be cleaned, checked and refurbished.

    -The propane tank was a little larger dimensionally (than the gasoline tank) and required a little trimming of the frame rail in order to fit. Quite easy since I own a MIG welder and and I work at a fabrication shop! Anyhow, once the tank was secured, I installed the propane specific fuel line. I also had to route the tailpipe in front of the rear wheel, exiting out the side. This was due to insufficient clearance between the tank and exhaust. Everything was installed neatly and in a safe manner. This rig had to pass a TSSA inspection and I wanted to be on the good side of the inspector doing so!

    A quick run-down on propane.

    -The liquid propane travels from the tank into a "vacuum lockoff". (This also doubles as a fuel filter.)

    -From the lockoff, the propane travels into the "vaporizer". There it changes from a liquid state into a gaseous state.

    -Then from the vaporizer, the converted propane travels into the "mixer". This is where the primary air and propane get mixed.

    Pretty straight forward so far! Okay then, here are a few more things that you should know.

    -I left all the wiring intact.
    The Jeep wiring for the sending unit has now been used on the propane sending unit. These sending units are "Ohm specific", just like factory. Example: My Jeep needs 220 Ohms at empty and 20 Ohms at full. Therefore, my sending unit says "220-20". This allows to reuse your existing, in-dash fuel gauge.
    I left the fuel injectors intact and still wired up. All I did was remove the fuel line and cap the fuel rail. This was done for two reasons.
    1) If you're in the bush, or wherever, and run out of propane, you can easily rig up a Jerry can with a fuel pump inside. This is not ideal but it beats a large tow bill.
    2) The factory PCM still looks for inputs from all the sensors! This is important because the 42RE transmission is electronically controlled and I can assure you that mine works just fine!
    I did install a "start assist" valve in the vaporizer. This is operated from inside the Jeep with a momentary-on push button switch. (I installed the switch beside the headlight switch for convenience). It merely assists in starting a cold engine by "priming" the engine with propane. Essentially, en-richening the mixture slightly.

    After I finished the conversion, in my driveway I might add, I had to get the truck to the propane inspection facility. In this case, I simply took a forklift tank from work, secured it in the cargo area and ran a proper flexible fuel (cheater hose) line into my existing fuel line. At the inspection station, they have to pressurize the propane tank (on the vehicle) to a very high pressure. This is how they checks for leaks before filling it up with propane! If it passes, the guy will remove the forklift tank, remove the cheater hose, reattach the proper propane line and transfer the contents of the forklift tank into your tank!

    A few last things.
    -Emission testing will still have to be done! I did mine prior to the conversion so I have two years to make sure everything is good.
    -Cost of fuel. I pay 49.9 cents per litre for propane in Waterloo, Ont. This hardly fluctuates, unlike gasoline.
    -Cost of my conversion. I'll have to tally this up but a ball-park estimate is $700. You can do this cheaper if you find a donor car.
    $50 for tank.
    $180 for 18' of fuel line. This was bought new!
    $50 for the vaporizer and fuel lockoff.
    $80 for the mixer.
    $100 for vaporizer and lockoff rebuild kits.
    $100 for miscellaneous items. Clamps, sandblasting of tank, sending unit, etc.
    $100 for inspection, mandatory propane stickers (two needed-one on windshield and one on rear tailgate) and a fill-up!

    The parts list: Propane tank made by Manchester tank-23 gallons.
    Sending unit, 220-20 Ohm-made by Rochester gauge. (1996-1998 uses 220-20 Ohm, other years may vary!)
    Fuel lockoff, Impco VFF30. (Vacuum lockoff with wick filter inside).
    Vaporizer, Impco model "E"
    Mixer, Nolffs CA-200. (Same as Impco model CA-200).

    I hope this thread helped seeing as the propane conversions aren't quite so popular. Enjoy the pictures and have a super day!


    Click image for larger version. 

Name:	Air Intake.jpg 
Views:	13 
Size:	998.4 KB 
ID:	87065Click image for larger version. 

Name:	Crossover.jpg 
Views:	14 
Size:	1.02 MB 
ID:	87066Click image for larger version. 

Name:	Dash Switch.jpg 
Views:	14 
Size:	995.7 KB 
ID:	87067Click image for larger version. 

Name:	Ground Clearance.jpg 
Views:	13 
Size:	1.07 MB 
ID:	87068Click image for larger version. 

Name:	Hose Routing.jpg 
Views:	15 
Size:	995.5 KB 
ID:	87069Click image for larger version. 

Name:	Tailpipe.jpg 
Views:	12 
Size:	1.06 MB 
ID:	87070Click image for larger version. 

Name:	Propane Conversion (3).jpg 
Views:	26 
Size:	1.01 MB 
ID:	86799Click image for larger version. 

Name:	Propane Conversion (5).jpg 
Views:	29 
Size:	945.5 KB 
ID:	86800Click image for larger version. 

Name:	Propane Conversion (1).jpg 
Views:	26 
Size:	926.0 KB 
ID:	86801
    Last edited by Spyder; 10-26-2013 at 10:44 AM.

  2. #2
    Join Date
    Sep 2002
    Location
    Redacted
    Posts
    4,997
    My Mood
    Aggressive
    Time Online: 4 Wks 1 Day 8 Hrs 33 Mins 45 Secs
    Avg. Time Online: 2 Mins 24 Secs
    Rep Power
    20
    What is your fuel mileage like?
    How is the power? I have heard that a propane conversion takes away power and lowers fuel mileage....what have you noticed so far?
    Any plans for a skidplate on those tanks? They have down awfully low for a Jeep.
    PAX ARMIS ACQUIRITUR
    99 TJ, HPD60/14B, TMR Customs 3 and 4 link, 40's.

    Project Sandstorm Remix

  3. #3
    Join Date
    Jan 2009
    Location
    Kitchener, Ontario
    Posts
    9
    Time Online: 9 Hrs 1 Min 23 Secs
    Avg. Time Online: 1 Secs
    Rep Power
    9
    Quote Originally Posted by Punisher-One View Post
    What is your fuel mileage like?
    How is the power? I have heard that a propane conversion takes away power and lowers fuel mileage....what have you noticed so far?
    Any plans for a skidplate on those tanks? They have down awfully low for a Jeep.
    -The fuel mileage is "close" to this, $9.00 for every 100 KM. I put on 300 KM per week (combined highway and city) and I spend $25 to $28 to fill.
    -The power is very comparable! Yes, propane has less BTU per litre than gasoline. With having said that, I'll use "slightly" more propane to go the same distance as I would running on gasoline. Not by much mind you and my cost savings running on propane makes it okay in my book. If you're ever in my area, I'll let you take it for a drive. You can judge the power and drivability first hand.
    -This Jeep is driven primarily on-road. There is a small skid plate on the tanks to protect the valve's and fuel level gauge. I'll look into something beefier in the spring. They hang down a little more then I like but this is a stock height vehicle. After the lift and bigger tires, it'll be much better. I haven't measured the ground clearance but it looks close to what I had when the regular gasoline tank was in there. It could also be the camera angle that I was on when the picture was taken. I'll add more picture's to the post when I get another nice day and some spare time.

  4. #4
    Join Date
    Dec 2012
    Location
    Kitchener, ON
    Posts
    0
    Time Online: 26 Mins 25 Secs
    Avg. Time Online: N/A
    Rep Power
    0
    Woohoo! Someone else in KW running propane!

    I have to ask, where did you get the parts? I need to buy a new lock off and the only places I can find online are in the US and want ridiculous amounts to ship parts... Like $60 ridiculous. Anywhere local in Kitchener by chance? Or even Toronto?

  5. #5
    Join Date
    Dec 2012
    Location
    Kitchener, ON
    Posts
    0
    Time Online: 26 Mins 25 Secs
    Avg. Time Online: N/A
    Rep Power
    0
    Well, I managed to find the place myself. R&R Forklifts in Kitchener. They showed me their "stash". All the stuff you need for a fumigated conversion, and they said if I wanted injection parts, they can source them as long as I let them know what I want.

  6. #6
    Join Date
    Jan 2009
    Location
    Kitchener, Ontario
    Posts
    9
    Time Online: 9 Hrs 1 Min 23 Secs
    Avg. Time Online: 1 Secs
    Rep Power
    9
    Quote Originally Posted by shepd View Post
    Woohoo! Someone else in KW running propane!

    I have to ask, where did you get the parts? I need to buy a new lock off and the only places I can find online are in the US and want ridiculous amounts to ship parts... Like $60 ridiculous. Anywhere local in Kitchener by chance? Or even Toronto?
    -I bought the propane tank from Discount Auto wreckers. The vaporizer and lock-off was found at County Choice. (Dan keeps all the propane stuff in a pile but the selection is now a little less because of what I bought! Hee hee.) As for new parts, R&R forklift is a decent choice. (Forklift's use many of the same components.)
    -I guess us propane guys are few and far between!

    Quote Originally Posted by shepd View Post
    Well, I managed to find the place myself. R&R Forklifts in Kitchener. They showed me their "stash". All the stuff you need for a fumigated conversion, and they said if I wanted injection parts, they can source them as long as I let them know what I want.
    -You were quicker in replying! Yes, R&R forklift is whom I would recommend on anything brand new. They also have fittings, lines, etc in their warehouse. The guys there seemed knowledgeable and were quick to get what I needed. I haven't had a lot of hands-on experience with the liquid injection but if I were to go that route, I'd call Greg Pilecki at Downtown Auto. He really knows his stuff and is very pleasant.
    Last edited by Spyder; 01-01-2013 at 09:37 AM.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •