LPG - Smelly exhaust

Post by **Donald360** » 31 Jul 2008, 10:03

Just recently got our van, a 1985 1.9 watercooled, converted to lpg. I have noticed that the exhaust fumes when running on lpg have a very strong and slightly 'gassy' smell. Can anyone tell me if this is normal? I don't know if there is a stenching agent put into lpg (like for domestic gas) or is it indicating a problem, eg wrong gas/air mix or something?

Any clarification would be really helpful.

Donald.

Post by **AngeloEvs** » 31 Jul 2008, 13:09

Sounds like unburnt gas, could be running a tad rich at idle or 'priming' for a little too long, (check the airfilter!). What sort of mpg you getting? Haven't noticed a smell of lpg on mine so yours might need adjusting or possibly the choke isn't dropping out quick enough. How does it idle on petrol? Is it a recent install and has the system been re-adjusted after the first 1000 miles? Adjustment is usually required after the vapouriser has been heat cycled. I would take it for a CO emmisions test to a LPG installer. It doesn't cost much and you will have a properley set up system and peace of mind. I, and a few others, carry out minor adjustments but only to compensate for driving style/power preferences and usually only after the system has been initially set up correctly and re-adjusted once the vapouriser has been heat cycled. If you do take it in, get them to point out the following adjustments/components for your system:-

The Diaghram Spring Pressure

The Idle Bleed Screw

The 'power valve' as it is sometimes referred to and where the mixer is fitted?

The 'priming' adjustment (on the rear of the switch unit)

You should have a safety certificate that states which LPG conversion is installed. OMVL, BIGAS, AUTRONIC, etc. If you don't then ask them.

Post by **Donald360** » 01 Aug 2008, 14:05

Thanks for your reply. The system was fitted several years ago by MSS Autogas Centre, Mickleton, Co. Durham. I was not given any info about the system when I bought the van a few months ago - and didn't know to ask about it at the time. So I don't know what type it is and there is no certification for it. I tried phoning the garage, but they weren't very helpful, their records don't go back far enough.

I'll take it along to a local lpg fitter and see what they can tell me. I haven't done enough miles yet to really figure out mpg. What should I expect in the way of mpg?

Cheers,
Donald.

Post by **AngeloEvs** » 01 Aug 2008, 16:26

If you browse this forum you will see a lot of threads relating to MPG on gas. 22mpg seems a fair average for a reasonably well set up system. It can be higher or lower but much depends on weight, driving conditions, etc.
Check your log book and see if it has been ammended for "Petrol/LPG' or 'Dual Fuel' in the Fuel description. If not then DVLA need to be informed and you will need to provide them with evidence (safety cert or verification from a local garage).

I would def. have the safety cert done if the company who did the conversion cannot give you a duplicate (most insurance companies will require this even if they do not ask to see it!). The safety cert. inspection should include a CO emmisions test. (I paid 65 pounds)
As I said, get them to go over the system with you so that you are familiar with the various components/adjustments. It will make things a lot easier if you later post questions or browse this forum.

Post by **Donald360** » 04 Aug 2008, 00:10

Getting about 16mpg on lpg at the moment. I'm taking the van in for a check with an autogas garage this week, so we'll see if this can be improved.

Post by **Donald360** » 04 Aug 2008, 19:28

The chap at Anderson Motors in Kirkcaldy had a quick look at my lpg system. He said that he was not able to do a safety check on it as it would, he was sure, need some parts replaced and the system was different from what he usually works with.

He reckoned that some of the hoses would need replaced and he also pointed out a gas valve that appeared to be missing a solenoid. He was also a bit doubtful about the condition of the underslung tanks.

I'm feeling a bit unhappy about this at the moment. I just cannot afford expensive alterations/repairs to the lpg system right now. I never asked about possible adjustments that might help with my mpg.

I think I will get back on the phone to the garage that fitted the system originally and see what they suggest.

Post by **AngeloEvs** » 04 Aug 2008, 19:49

Earlier installations didn't require the LPG filter to incorporate a shut off solenoid and that may be the one he is refering to. They aren't expensive and it shouldn't cost too much to replace/update. Shop around if you can (once he tells you exactly what needs doing and gives you an estimate).
My old Sierra still has the early installation and I never upgraded it to satisfy the current COP11 safety regs as I still have the original certificate. Try and get a duplicate safety cert from the garage that installed it. When you can afford it, upgrade it!