Can we use LPG in old car

[danish2490910]

I have Margalla 1999 model. Jo aitna use nahi hoti or (i guess low usage ki waja sy us ka fuel pump khrab ho jata hay) Mechanic k raha hay k LPG per convert kr lo. (CNG kit and cylinder already installed). or sath my universal wala fuel pump lagwa lo. Q k wo engine my lagta hay. to us k conection is thrah kr do ga k use krni hoi petrol per tb phly pump ka grip laga lena or phir car ready to go.
Experts mashwara dein ka ya sahi hay ya nahi.
Thank you.

[Massive_One]

bilkul , ap LPG per aram se chal saktay hain old car..
my brother is running his Khyber 2000 model on LPG for the past 2- 3 years and is really happy with it getting 18+ km in city and 25-28 km on long drive : )
another person in relatives is running his Alto 2010 on LPG for past 2 - 3 years, same results, no trouble at all ..

[brownrose78]

Yes you can easily convert that car with existing CNG kit and cylinder into LPG.

Your Mechanic is partially right but half wrong. You don't have to physically remove grip each time or frequently.
Just install electrical/ Electronic fuel pump within engine bay because if you want to run it on gas then in case of mechanical pump, it will work Continously without petrol so in it's lines, it will run dry and will die eventually.

In case of electrical pump, it's electrical connection will be off by CNG switch button thus it will not run dry so more successful in gas running vehicles.

If you are in Karachi, visit Ameer gas center at Sohrab goth

[danish2490910]

Thanks brother for your kind reply.

[danish2490910]

The Original fuel pump has fitted into the fuel tank of the car. The mechanic was saying Due to less usage pump got die. and that pump is expensive and also takes time to change because we have to empty the tank then open it and change that pump. As he was saying there is no indication of remaining LPG in the cylinder So if suddenly LPG got to the end just change the switch from the converter(that pump will start working if possible) other wise you have to connect the grip and use the car on petrol. Here is the image of pump he was talking about. No I am From MULTAN. Thanks.

[Massive_One]

The Original fuel pump has fitted into the fuel tank of the car. The mechanic was saying Due to less usage pump got die. and that pump is expensive and also takes time to change because we have to empty the tank then open it and change that pump. As he was saying there is no indication of remaining LPG in the cylinder So if suddenly LPG got to the end just change the switch from the converter(that pump will start working if possible) other wise you have to connect the grip and use the car on petrol.

i don't think you have to empty the fuel tank to access fuel pump, as you will see in multiple videos on youtube, fuel pumps are accessed and removed easily from above the fuel tank of cars .. it is an expensive item though, but he is right.. there is no guage for LPG indication .. if by any chance the LPG cylinder is empty, you can switch to petrol , but for that your fuel pump should be working...
watch "Mansoor Ahmad EFI AC & Hybrid Auto Workshop" youtube channel, he performs this fuel pump removal and cleaning procedure a lot on his channel.

[helper_learner]

I don't know why people do it, Simply add a return line after pump, and This

on pipe before it goes to carb.

Connect it just like it is connected on CNG, with cng switch. Toggle it and it will be on LPG and On petrol.

Neither pump will run dry, and it will still be able to work on LPG / CNG

[helper_learner]

As he was saying there is no indication of remaining LPG in the cylinder So if suddenly LPG got to the end just change the switch from the converter

Why it is like this?

Add this LPG gauge, then you can see remaining lpg on that gauge under hood.

Secondly you can also find something like this.

https://leiliyk.en.made-in-china.com/product/nXDxOgMbXihL/China-Air-Conditioning-Low-Pressure-Switch-for-Car-AC.html

Connect it with a light that when pressure reach 30 PSI it will turn on the light like RESERVE light.

[Xulfiqar]

This was standard issue install when carby cars were converted to cng

[danish2490910]

Brother thanks for your reply. Already installed that type of gauge for When the car was on CNG that's work fine. Mechanic is saying there is no indication and one of our brother @Massive_One has also told above that they are using there car's on LPG from past 2-3 years. He is also saying that there is no gauge for LPG to know about remaining in cylinder. Please tell me if you have personal experience with this gauge. Thanks.

[helper_learner]

This gauge is commonly used on lpg Cylinders. The difference between this and Cng one is just pressure range.

[helper_learner]

Sir is my theory regarding return line is fine?

I am suggestion something like this.

[Hassan1991]

No. Fuel will continually go back through the return line. Even if valve is open. As there's no restriction in the return line.

[helper_learner]

So we can add another normal open valve.

[helper_learner]

Or may be this

[Hassan1991]

These valves were located before the fuel pump in mechanical drive systems. Meant to hold the fuel in lines when car's off.

[helper_learner]

Yes, But due to that pump runs dry. I am suggesting it so pump does not run dry.

[Hassan1991]

Right. Then adding it on pump output line will work as you drawn.
I might misunderstood your picture.

[Xulfiqar]

its better to have a switch with a neutral position, where the pump shuts off but gas is still not admitted, till the carb runs dry - like the ancient CNG systems.