Lpg in a Merc clk 3.2 v6

[tom-madbiker]

I'm thinking of getting one for the missus anyone know of any issues when fittin lpg I will do the install myself

[tom-madbiker]

On another note I'm looking for a new wiring loom for a aeb 2568d 6 to 8 cylinder ECU if any one knows where I can get one tinley tech don't have one on their website but I have not rung them yet

[LPGC]

The CLK320 is relatively straightforward but as with most Mercs you need to think about how to plumb the reducer to hot water.

[tom-madbiker]

Thanks Simon I am going to look at it this afternoon see how it looks it's a pressie for the missus but I need to make sure I can afford to run it

[Gilbertd]

Blimey, that's a bit OTT isn't it? Mine got a C180 for her 50th (although I did get her a personal plate to go on it too). She's since sold that and bought herself an SLK280.....

[tom-madbiker]

I got it and she loves it amazingly most of the electrics work it's an aventgard so a nice spec now I need to gas it as it does use a bit of fuel anyone know what size gas tank I can get in it I am going to use one of my spare aeb ecus Tinley tech got me a new loom for 25 quid delivered need to just get a few bits so I have all the parts to do it tank,vaporiser, switch,filter, and fill point and a few ancillarys

[LPGC]

I converted a 2003 model CLK around this time last year, fitted a 630x270 61litre 30 degree GZWM brand tank.

Check under the spare wheel well before making holes etc! A lot of Mercs including some CLK's have plastic trim and/or the charcoal cannister (for the evap purge system) under the spare wheel well.

[tom-madbiker]

Thanks for that Simon I need to get this lpg converted quickly it's not cheap to run I'm going to check about where to fit stuff and if there is anything under the spare wheel well seem to have been doing all the little things that a new old car needs when you first get it lower ball joints was yesterday still overall I'm pretty happy with it and the missus loves it

[LPGC]

I meant to include in my last past - Some brand 30 degree (internal) spare wheel tanks have the hole for pipes and vent pipe that go through the floor off-centre. If there are vehicle components under the spare wheel area you can sometimes select a tank brand that has the piping/vent pipe tube on or off centre to avoid the components. Or move the components.

[tom-madbiker]

Did a quick measure earlier and I think that it will only take a 630 x 250 under the boot floor

[LPGC]

Did a quick measure earlier and I think that it will only take a 630 x 250 under the boot floor

Boot floor level being the usual height of the boot floor carpet?

That may be so but a 270 height tank will fit neatly while only raising the floor level by less than 20mm and at the same time giving greater on board gas capacity (and range). For most people the best compromise would be to lose some mm of boot floor height to gain the extra 8% onboard LPG capacity and range but the choice is yours.

[tom-madbiker]

Another quick one that may cause a lot of discussion I have always used copper pipe for all my installs however I was considering using faro poly pipe as on the Merc are there any downsides

[LPGC]

There was a time when Faro / synthetic high pressure LPG pipe wasn't available, so in those days there really was only copper (autogas spec copper though, with the plastic outer sheath). But as soon as polypipe became available it made a big impact on the scene because it is so much easier to route under vehicles. Faro is just one brand name of polypipe but it is by far the most popular brand.

The downsides of polypipe compared to copper are: it's even more important to maintain distance from heat sources (hot exhaust) for obvious reasons. Although polypipe is in most situations more flexible than copper, copper will retain it's shape (once bent into that shape) whilst Faro's flexibility can mean you might need a clip in a position where you wouldn't need a clip if using copper (and that clip might need to go in an awkward to access position, e.g. above a drive shaft that is between suspension arms on a rwd vehicle). Poly is more flexible than copper, yet ultimately copper can be bent into a tighter bend without kinking than polypipe.

But the upsides of Faro still far outweigh the downsides, plus it won't corrode (we all know copper brake pipes corrode) like copper pipe might if the plastic outer covering is chaffed. Two dissimilar metals in electrical contact and in the presence of water means electrolytic processes will take place but that cannot effect polypipe. I wouldn't like to think I had to go back to fitting copper pipes under vehicles! Will say that there are sometimes small sections of routing where I think 'this section would have been easier with copper than poly' but still the overall routing is almost always easier using polypipe.

[tom-madbiker]

I was thinking of using a magic 111 reducer has anyone used one are they any good

[Pinger]

I replaced the copper pipe with poly and the most difficult part was removing the old copper pipe due to the rigidity of it as alluded to by LPGC. And that was on a pretty roomy truck.
The only reticence I have with poly is brass on brass fittings. I prefer dissimilar metals - hard olive biting softer pipe - but brass on brass is all there is. I fitted tethers to stop the union completely flying apart in the event of the olive losing its grip. Probably/possibly overkill due to my paranoia of the engine bay getting flooded with LPG if a fitting slipped (I have two unions directly above the distributor). That said, a few years down the line and there's been no problem with the poly whatsoever.

[tom-madbiker]

Also what size nozzles do people suggest I was thinking about 3mm although I may get smaller and machine them out if nessasary

[LPGC]

MJ reducers are a good bit of kit. Up until a couple of years ago the Compact versions were adjustable between around 0.8 and 1.35 bar but the later ones are adjustable between around 0.8 and 1.7 bar.

The best nozzle size is affected by what make/model injectors you're using and sometimes by what pressure you're intending to run, while available pressure range can depend on what spec reducer you're fitting... Or looking at it another way, need to consider injectors, nozzle size and reducer all at the same time.

What injectors are you fitting?

[tom-madbiker]

I am going to use some omvl 3 ohm injectors as I have some lying around and the 8 cyl aeb ecus I have I did a basket for lpg auto supplies (tinley tech) and put a kme gold reducer in however I'm up for suggestions on another note I did notice poly pipe is a lot cheaper than copper

[LPGC]

If they're OMVL Superlight injectors - The nozzles are small and fiddly so can be difficult to drill without messing up the small allen key socket. They're also difficult to get hold of in sizes other than the size they come supplied with, which may be 1.5 / 2mm but seldom 2.5mm. So your best bet with OMVL SL injectors may be to run them without nozzles (just remove them and leave them out) but then you'll probably only need 1bar pressure.

[tom-madbiker]

They are omvl dream XXI injectors with the alloy body as for machining the holes larger I have a shed full of machine tools and I trained as a toolmaker