Topic: Let the LPG questions begin... (Read 5257 times)

Brynjaminjones · « **on:** May 16, 2015, 11:13:35 PM »

I've had a little chance to play with the LPG system on the new ZJ over the last couple of days, and was wondering if you guys could tell me things to check.
The car runs perfectly on petrol.

When I press the LPG button, it runs on petrol for a minute or so with the LPG light flashing, then attempts to switch over. Most times it sputters and nearly dies when it switches, then quickly reverts to petrol and the LPG thing flashes red.
Once when it switched over at idle in traffic it ran for a couple of minutes on LPG fine, but sputtered an switched back to petrol when I accelerated.

The system is a multipoint/sequential system made by BiGas, installed in 2007. The LPG tank is full.

Is there anything I can check before taking it for an LPG service?

Cheers!

bigjeepzj · « **Reply #1 on:** May 17, 2015, 04:14:06 AM »

Check that the evaporator is drainedof oil.
there's a screw/nut on the bottom you undo

georgen · « **Reply #2 on:** May 17, 2015, 08:51:35 AM »

Also check the filter normally just a strainer filter, LPG is dirty stuff.

JamesH · « **Reply #3 on:** May 17, 2015, 10:15:28 AM »

Can you take a photo of the engine bay so I can see the different components in there? I like to be able to visualise it.

My LPG system was an OMVL multipoint and did similar things a few times. Changing distributor cap, rotor arm and leads was always a good way to stop spluttering and hesitation but normally it wouldn't be bad enough to switch back to petrol. I managed to catch the wiring when off-road and this caused it to keep switching back to petrol (I can't remember exactly what the wiring looked like but it was 'pulled' rather than completely disconnected so I just replaced the whole section. I never had a problem with the filter on mine but for a few quid it's worth changing.

I did have the diagnostic lead and software for mine and once when it was really playing up I did have to re-programme it. Only a case of connecting and following auto setup guidance on the laptop.

XJ Fan · « **Reply #4 on:** May 17, 2015, 04:38:49 PM »

Where can one find the evaporator and filter?

jay140285 · « **Reply #5 on:** May 18, 2015, 09:17:24 AM »

Second the comment on checking the LPG filter, on our V8 after 12 months on a new LPG installation at its first service the filter was filthy and desperate for a change.

Brynjaminjones · « **Reply #6 on:** May 18, 2015, 11:40:42 AM »

Cheers guys, I'll check this out. I've had a quick look and it looks to me like some of the hoses could need replacing, and the evaporator looks quite dirty.
I'll upload a photo this afternoon of the engine bay!

Brynjaminjones · « **Reply #7 on:** May 18, 2015, 01:31:55 PM »

I've found the biggest problem with the system, and you'll never guess what it was...
The tank was empty! I filled it up and bar a slight misfire at idle, it drove home perfectly! I now need to check the LPG gauge, as it was reading full before filling.

This Jeep just keeps getting better and better!

JamesH · « **Reply #8 on:** May 18, 2015, 01:50:46 PM »

Start with the obvious! Good work

jay140285 · « **Reply #9 on:** May 18, 2015, 08:24:53 PM »

Stands a chance the float in the lpg tank is stuck in the full position. Best thing will be to brim the lpg tank and reset the tripmeter. Run it empty and each fill up reset and use the miles as an indicator. It's what I used to do as lpg never reads correctly in a tank

Brynjaminjones · « **Reply #10 on:** May 18, 2015, 08:46:38 PM »

That sounds like a possibility. I've been running it on LPG all day now and it definitely has a misfire at idle that needs sorting, but I think a good tune-up could sort that.t
I'm going to get the LPG system serviced regardless, as some of the hoses etc. have seen better days.

XJ Fan · « **Reply #11 on:** May 18, 2015, 09:39:27 PM »

Quote from: XJ Fan on May 17, 2015, 04:38:49 PM

Where can one find the evaporator and filter?

Brynjaminjones · « **Reply #12 on:** May 18, 2015, 09:50:12 PM »

The next thing I'd like to know is what ignition components to use?

I'm going to replace distributor cap and rotor, spark leads and plugs. Should I use the normal Champion plugs with a smaller gap? Should I get better spark leads?

Brynjaminjones · « **Reply #13 on:** May 21, 2015, 07:53:53 AM »

New Jeep has had a spending spree over the last couple of days. I've ordered new:-

Cat-back exhaust
Boot struts
Spare tire holder
High performance distributor cap and rotor
8mm silicone HT leads
Champion spark plugs
Air filter
Oil filter
Full-synthetic oil
Fan belt
Windscreen wipers

She should be healthy after all of that, but I have now noticed an LPG leak from one of the pipes going from the 'injector rail' to where it's injected.
Am I right to assume that I should stop driving on LPG and take it straight to an LPG place to get the pipes replaced?

jay140285 · « **Reply #14 on:** May 21, 2015, 11:10:14 AM »

If its an LPG leak then yes, but lpg is a gas so how have you noticed it?

Brynjaminjones · « **Reply #15 on:** May 21, 2015, 11:21:23 AM »

When I moved a pipe whilst changing the fan belt yesterday I could hear a light hiss. It would start and stop as I moved the injector rail or the hose from the regulator to the rail. When it leaked it smelled of gas.
It seems to be coming from one of the connections, and it stopped once the pipe to the rail became empty. Now that that part of the system is empty and no longer hissing, am I okay to disconnect and reconnect injector hoses?

jay140285 · « **Reply #16 on:** May 21, 2015, 11:23:31 AM »

Just do it in a well ventilated area.

I had a leak on mine after the head rebuilt, Still ran just smelled of Gas. Ended up been sorted when the LPG was serviced.

Brynjaminjones · « **Reply #17 on:** May 21, 2015, 11:28:37 AM »

Awesome, I've got it booked in next Tuesday and is getting a quote tomorrow, but I've got a lot of driving to do this weekend and little money, so want to do so on LPG if possible! The leak was only temporary, so I'm wondering if that was what was causing my intermittent misfire...

JamesH · « **Reply #18 on:** May 21, 2015, 01:21:43 PM »

Use a mix of washing up liquid and water in a spray bottle for detecting leaks. There will be bubble created from even a small leak when you spray it on the pipes and connections. It might be a small leak that you can fix with a new jubilee clip.

georgen · « **Reply #19 on:** May 21, 2015, 03:42:44 PM »

Quote from: XJ Fan on May 18, 2015, 09:39:27 PM

Quote from: XJ Fan on May 17, 2015, 04:38:49 PM
Where can one find the evaporator and filter?

Take some pics and we will point them out, but filter will be inline with the lpg fuel pipe and normally under the bonnet, the evaporator will be a large lump that looks like it should not be there with your coolant hoses altered to feed to it.

Brynjaminjones · « **Reply #20 on:** May 21, 2015, 04:54:11 PM »

Quote from: JamesH on May 21, 2015, 01:21:43 PM

Use a mix of washing up liquid and water in a spray bottle for detecting leaks. There will be bubble created from even a small leak when you spray it on the pipes and connections. It might be a small leak that you can fix with a new jubilee clip.

I've reseated all the LPG hoses now, and cut split ends off some vacuum hoses and reconnected, and after running it again I couldn't find any more leaks by sound or smell...

bgbazz · « **Reply #21 on:** May 21, 2015, 06:28:39 PM »

Good to see you addressing the problem...the testing hint from James is the best way to start...I use that method any time I suspect a leak...even on a tire that loses pressure over a few days!!!

Bubba · « **Reply #22 on:** May 23, 2015, 06:13:38 PM »

well done one step at time mate

Brynjaminjones · « **Reply #23 on:** June 07, 2015, 11:08:28 PM »

LPG has been serviced and leaks fixed. All new ignition system hasn't stopped misfire, but has been diagnosed as needing two new injectors. All are being replaced on Tuesday so hopefully all will be good after that!

Author Topic: Let the LPG questions begin... (Read 5257 times)

georgen

jay140285

jay140285

jay140285

jay140285

georgen