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Anyone here running their W126 on LPG. I looked at a 380SE that was running on LPG last week but the owner decided not to sell it. ???
I then found a very good looking 420SEL with 459,000 km's on the dial. (my wife had a fit when she found out the mileage, but it is so sweet to drive except for the rear suspension.
So any experience of LPG out there. It costs about 66C/lt here in Perth at the moment, as against A$1.49/lt for petrol and the gov. pays A$3000 towards the installation costs. I got a quote of A$3200 to install but guy says he has not done one before. If anyone has a 380/420 converted can they please let me know what the mixer is called, numbers etc.
Thanks in advance,
BrianD.
 

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Anyone here running their W126 on LPG. I looked at a 380SE that was running on LPG last week but the owner decided not to sell it. ???
I then found a very good looking 420SEL with 435,000 km's on the dial. (my wife had a fit when she found out the mileage, but it is so sweet to drive except for the rear suspension.
So any experience of LPG out there. It costs about 66C/lt here in Perth at the moment, as against A$1.49/lt for petrol and the gov. pays A$3000 towards the installation costs. I got a quote of A$3200 to install but guy says he has not done one before. If anyone has a 380/420 converted can they please let me know what the mixer is called, numbers etc.
Thanks in advance,
BrianD.
You are going to get Teutoned(tm) or Cascaded(tm) very soon if you don't search the forum, since we have already covered that topic here.

Here in Peru many cars run on LPG and CNG. Basically any gasoline car can be converted to LPG, the conversion is really brand-independent. Progas (Progas - Professional Performance -- argentina) sells a mixer specially made for the V8 motors (it lists as Mercedes V8 500 SEC mixer), and i bet many more companies have a mixer that fits perfectly. By the way, on these cars the mixer is usually installed on top of the air flow sensor plate, so you don't remove the K-jetronic system and thus the car remains dual-fueled (LPG or gasoline/petrol).
 

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You are going to get Teutoned(tm) or Cascaded(tm) very soon if you don't search the forum, since we have already covered that topic here.
Or he gets Jeroened!
Not too many cars on LPG on this forum so there's not much info in the archives.
Please (re)read the "welcome to the forum" sticky on the first page.
It'll show you how to fill out your profile and do a forumsearch.

gr J
 

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I have LPG in my 500SE. No problems so far, the setup is a Lovtec(Lovato)+BRC combination. The cost of installation was 27 000 CZK ($1600). The car draws 13-18 l/100km (about 2 liters more than gasoline) - it's not a direct injection (btw don't try it, too expensive and AFAIK will not work in M116/M117!).
Also, the car idles much smoother and has a lot more torque in low/mid RPMs. It only lacks power above 5000 RPM (but still beats gasoline power :)).
 

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Yes, member Andrew SL&SEL has put his 420 SEL on to LPG and is very happy running on LPG - it doesn't matter which mod it is - if ou haven't used the search function, you will be told to...
 

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Yes, member Andrew SL&SEL has put his 420 SEL on to LPG and is very happy running on LPG - it doesn't matter which mod it is - if ou haven't used the search function, you will be told to...

Pretty close on the username Ross ;)[thats my ozbenz username] but to make it easy for Brian, here is the thread link.

http://www.benzworld.org/forums/w126-s-se-sec-sel-sd-sdl-class/1326531-just-got-great-lpg-dual-fuel-conversion.html?highlight=lpg

It seems LPG is mainly an Aussie or Euro mod as our American friends still have cheap petrol and really don't seem to need that LPG fuel saving. The other big tip for fitting LPG is to always start and warm up the car on petrol. Switch it to LPG for driving but switch it back to petrol when you park. It stops the fuel distributor from drying out and helps ease the burden on the valve seats. I generally run the car on petrol for short trips and use the LPG for the long drives. Touch wood, it's running like a dream:thumbsup:

Please fill in your signature so we can get a bit more info about you and your car Brian.

Cheers
 

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Just an FYI.

I think I remember someone recently asking about stiffer springs for the rear of his 420 SEL.

The owner had installed LPG equipment and tank in the trunk and now the car's rear end was sagging under the added weight.

You may want to consider a car that has the hydraulic Self-Leveling-System (SLS) rear suspension.
 

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I have regular (new) springs and regular (new) shock absorbers in the read, gas bomb in the trunk in place of the spare wheel, and I usualy travel with trunk full of junk - it's not sagging down...
 

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It will be my dream come true if I could convert my 560SEL to LPG/gasoline but I have yet to find a kit to do it. Every website I checked was vague in every aspect be it pricing or specs to make sure it would do the job for my car.
 

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It will be my dream come true if I could convert my 560SEL to LPG/gasoline but I have yet to find a kit to do it. Every website I checked was vague in every aspect be it pricing or specs to make sure it would do the job for my car.
You don't really need a kit. The important starting point is to buy a mixer that is specifically designed for your engine. This may come from Progas - Professional Performance (sorry i think it's only in spanish), or any other serious gas manufacturer (BRC for example).

The other important starting point is to get a vaporizer ("regulator", "reductor") that is adequate for the power of your engine. Bigger engine needs a bigger vaporizer.

The rest (tank, valves) are the same for all vehicles independently of the engine type and power.
 

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I personally advice AGAINST LPG installation in our cars. I just had the previous owner's set up tossed out due to problems in the 190. The distributor cap/rotor only lasted 15,000 km's! Also, since the LPG fuel is "dry"... it caused havoc on nearly ALL the rubber components in the engine bay. Whats worse is, if its not set up correctly... it can backfire like it did in my 190 and damage the potentiometer:rolleyes::mad: Unless the car is a basic carburetor engine such as the 280S... I would not think about installing LPG. From all the experts I've talked to on LPG, the all claim Mercedes' old fuel management system are difficult to tune after an LPG system installation.
 

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my car does not have the original merc engine , it now has a Toyota 2jzgte
360 bhp, can be tuned to 600 bhp from stock ,
it runs on LPG

60 liters was getting me 250 miles , but now i have cleaned air filter and keep away from using the twin turbos i am now getting 350 to 60 litres ,

it is a injection system into each cylinder

very smooth ride , and from the picture i do not think the rear of the car is down to much ,


hope this helps
 

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I personally advice AGAINST LPG installation in our cars. I just had the previous owner's set up tossed out due to problems in the 190. The distributor cap/rotor only lasted 15,000 km's! Also, since the LPG fuel is "dry"... it caused havoc on nearly ALL the rubber components in the engine bay. Whats worse is, if its not set up correctly... it can backfire like it did in my 190 and damage the potentiometer:rolleyes::mad: Unless the car is a basic carburetor engine such as the 280S... I would not think about installing LPG. From all the experts I've talked to on LPG, the all claim Mercedes' old fuel management system are difficult to tune after an LPG system installation.
If you follow the rules then it's no problem.
Once again of you leave it on LPG for an extended period of time the fuel system dries out and the you get issue with the fuel distributor and the fuel injection system. Start it and stop it on LPG, and only switch from one fuel to the other while stationary with the tacho on 2000 rpm. I've had no backfires since fitting LPG and the economy/power is sensational.

From what I understand talking to people in our MB club, on the forums and out and about, the issue with LPG on MB's is, people treat an MB dual fuel convertions like your basic Ford of Holden conversion.

That will lead to PAIN!
 

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I personally advice AGAINST LPG installation in our cars. I just had the previous owner's set up tossed out due to problems in the 190. The distributor cap/rotor only lasted 15,000 km's!
You should reduce the spark gap in 25% otherwise the arc voltage will raise far higher than in petrol. Your LPG technician didn't know about that.

Also, since the LPG fuel is "dry"... it caused havoc on nearly ALL the rubber components in the engine bay.
Petrol (gasoline) is actually a solvent, not a lubricant, so you can't blame this failure on the gas.

Whats worse is, if its not set up correctly... it can backfire like it did in my 190 and damage the potentiometer:rolleyes::mad:
Yes but this is not a fault of the gas "per se" but a consequence of the incompetence of the technician: It is caused by a sudden leaning of the air-fuel mixture. Which is caused by a bad installation (bad mixer, bad calibration)

Unless the car is a basic carburetor engine such as the 280S... I would not think about installing LPG.
For LPG there is no difference between the 280S and the 280SE since the carburator or the injectors are not used at all when the engine is on LPG.

From all the experts I've talked to on LPG, the all claim Mercedes' old fuel management system are difficult to tune after an LPG system installation.
Nonsense. They just don't have experience with K-Jetronic. This is typical also in my country. Many know what is a fuel distributor, a K-jetronic inyector, etc... But very few actually can calibrate the system.

Bottom line: Only install LPG if you have a technician who REALLY knows about engines, ignition temperatures, spark plug voltages, K-jetronic mixture adjustment, etc.
 

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Hi there,

Just my thoughts...

I've had a few months ownership of a 1991 420SE on LPG, its been very badly neglected and poorly serviced over the last 10 years, (I doubt it has been serviced more than once perhaps looking at the leads/plugs etc and looking at the last owner!) and still runs beautifully on Gas or Petrol- still with possibly 5 year old plugs, rotor arm etc...

1t is currently at 172k miles, converted at 35k and seems to have no ill effects on the car what so ever... infact, I doubt it would still be plodding along so well if it had been on petrol for all these years!

And its doing 30mpg around town (by price- LPG is half of Petrol here in the UK) and upto 55mpg touring, again by price.

No backfire, even at the red line.

I wouldn't go back to Petrol with a car this size.

Rex
 

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Hi there,

Just my thoughts...

I've had a few months ownership of a 1991 420SE on LPG, its been very badly neglected and poorly serviced over the last 10 years, (I doubt it has been serviced more than once perhaps looking at the leads/plugs etc and looking at the last owner!) and still runs beautifully on Gas or Petrol- still with possibly 5 year old plugs, rotor arm etc...

1t is currently at 172k miles, converted at 35k and seems to have no ill effects on the car what so ever... infact, I doubt it would still be plodding along so well if it had been on petrol for all these years!

And its doing 30mpg around town (by price- LPG is half of Petrol here in the UK) and upto 55mpg touring, again by price.

No backfire, even at the red line.

I wouldn't go back to Petrol with a car this size.

Rex
Thanks Rex, great to know!! Do you remember the make of the LPG equipment (specifically, the vaporizer)?
 

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LPG on W126

Hi folks,

I used to be pro-LPG but now, I have second thoughts.

LPG makes a hot running cylinder head and even hotter valves . As good as they are on a Benz, their life (valves) is shortened. Valve recession is also a possibility.

If you have ethanol around, I'd say its a much safer option to save running costs.

Cheers

Denis
Lion sur Mer
France
 

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Hi folks,
I used to be pro-LPG but now, I have second thoughts.

LPG makes a hot running cylinder head and even hotter valves . As good as they are on a Benz, their life (valves) is shortened. Valve recession is also a possibility.
Source? Where are the experimental facts? Temperature values?

I have already researched the topic and what i have found so far is that the valve seat temperature achieved with a LPG installation is the same as using unleaded gasoline. Both are higher than leaded gasoline. I have more explanations and discussions on this topic but they are in spanish... sorry.

Moreover, the savings earned by using LPG in my country would make me able to afford a new top end (i.e. valves, seats) job every year if i want to... and still be saving money.
 
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