does my lpg system require filters?

[digitalis1]

Hi have an s60 2.4 bifuel factory fit, had a few problems middle end of last year which required me having to have the lpg system changed to an aftermarket system. Have had a few niggles with the new system which meant i have had to take the car back to the installers to be plugged in, however i noticed that the lpg system does not have any filters fitted, i asked the installer if it required any filters and he said that it didn't however i am unsure, can anyone advise if they think i should have filters on the sysyem or is the installer correct. the aftermarket system is a sequential GIS bi gas
many thanks for your help
dave

[jimathan]

I change mine once a year. most of the time they are ok but now and then you get a bad fill and it does muck them up quite bad.
jim

[digitalis1]

hi jim many thanks for the quick reply, i thought that all lpg systems would have filters because of the detrus that may be in the gas, but the installer i used said they are not required, but my faith in this particular installer is falling quickly after some other problems during and after the install!! i am just wondering if there are any aftermarket systems that don't have filters fitted and if so could mine be one of them
regards
dave

[jimathan]

Possible I guess but I don’t see why. I drained down my tank after three years because of lean running at the top end, only to find about a pint of tar like stuff in the bottom of the tank.
jim

[digitalis1]

hi jim thanks again,
my car is due to have the lpg system serviced again in the next week to keep up the warranty, i will see if the installer can drain the tank at the same time, it is my belief that the lpg system should have a filter but would like to go armed with some evidence if this is the case
many thanks
dave

[jimathan]

Its a bit like saying "petrols clean, you dont need a filter"

[digitalis1]

very true jim! i think i will tell him that i want filters on even if he thinks otherwise, i would rather be overcautious than sorry with an empty wallet

[r800v6]

Hi,

Pretty much all LPG systems have filters.
The Romano is an exception as the injectors are serviceable but even then it should at least have one filter in the shut off valve.
The standard layout would be a liquid filter in the shut off valve which filters the 'gas' while it is in pressurized liquid form coming from the tank into the vapouriser/reducer/regulator (basically different names for the same unit)
After the vapouriser LPG passes to the injectors in gas form, before the injectors you would have a gaseous filter, usually a standard barrel shaped unit with either 10 or 12mm inputs/outputs.
The main systems being Prins, BRC, OMVL, Zavoli, Bigas, Stag, even the original kit you had fitted the Koltec CGI system has liquid and gas filters fitted.
Some of the early Koltec 'factory fitted' CGI systems never had filters in the gas side, for example on the VW LT35 the regulator and gas distributor are mounted side by side with only a 2 inch long pipe connecting them, however there is a liquid filter fitted.
The later Koltec GSI injection system has liquid and gas filters because the GSI system uses seperate injectors instead of a distributor.
The gas filter is purely to keep the injectors clean.

I have yet to work on any Bigas system without a filter and would always recommend having one in line before the injectors.

On another note, what was the reason the Koltec system was removed form your Volvo?
The 'factory fitted' kit has received a bad name of late mostly due to the inexperience of people working on them as they are not a well known system.
The koltec is actually a very good system but does require knowledge of the sytem to enable problems to be fixed, in all of the factory fitted systems I service and repair the main issues are-
Volvo- Dirty distributor unit which merely requires a good overhaul.
VW- Same as Volvo.
Vauxhall- Coil packs, EGR valve issues, and faulty GSI injectors
Ford- Dirty LPG distributor and faulty DPFE sensors.

Sorry to go on, basically if your system does not have a filter fitted, I would request one to be fitted.

Regards,
Edward.

[classicswede]

I can not think of any LPG system that does not have a filter.

All systems should have a filter in the tank as teh primary filter to stop bigger lumps coming through. You should then have filter mounted in the engine bay before the vapouriser on all systems.

Multi point systems then have a fine vapour filter to protect the injectors as Edward has mentioned. A bigas system will have been supplied with one and teh filter should be used. I would insist that they fit the filter as per manufactuers (Bigas) instructions. Tinely Tech sell Bigas in the UK so you could contact them for full details on the Bigas system.

Romano injectors are servicable but dirt in an injectors = incorrect fueling. Incorrect fueling results in missfires burnt valves and engine damage. All multi point systems should have a filter fitted regardless of how servicable the injectors are.

[classicswede]

Originally Posted by r800v6

Hi,
On another note, what was the reason the Koltec system was removed form your Volvo?
The 'factory fitted' kit has received a bad name of late mostly due to the inexperience of people working on them as they are not a well known system.
The koltec is actually a very good system but does require knowledge of the sytem to enable problems to be fixed, in all of the factory fitted systems I service and repair the main issues are-
Volvo- Dirty distributor unit which merely requires a good overhaul.
VW- Same as Volvo.
Vauxhall- Coil packs, EGR valve issues, and faulty GSI injectors
Ford- Dirty LPG distributor and faulty DPFE sensors.

Sorry to go on, basically if your system does not have a filter fitted, I would request one to be fitted.

Regards,
Edward.

Just to add on the factory fitted problems

Volvo - dirty distributor often cured by cleaning but also very common to be completly worn out. Very odd ocasions the motor will burn out. Gummed up LPG solenoid stopping the gas comeing through.
VW- same as volvo
Vauxhall - early system same as volvo. Later injection systems have faulty injectors causing missfires, vaporiser problems including lack of pressure or exessive pressure due to needing overhall.
Ford - the main problem I see is with liquide injection system and that is most of teh time a failed LPG pump.

With all LPG systems the main cause of missfire is nothing to do with the LPG system but the cars ignition system. Coils that are mounted directly to the engine in most cases have a limited life. The vauxhalls with the coil pack mounted in the head suffer badly and will first missfire on LPG then in time will also missfire on petrol. The 5 cylinder volvo's with the coils mounted in the head tend to fail at around 100,000 miles mark. Dealers tend to replace one at a time but I would recomend changing the set. Ford V6 as fitted to the cars badged as Jaguar suffer very badly. So much so that Ford has dropped the price of teh coils right down as they are more or less a service item!!!