Don't run out of petrol

r.g.nixon, Oct 31, 9:13pm
You know how they say "Don't let your car run out of petrol"?
Because there will be gunk at the bottom and it will clog up your fuel filter and carburettor etc?

I can say I have well and truly tested this and proven it correct. Well at least I no longer have any water in the tank as well. Several hundred dollars - I'll remember now for sure!

johotech, Oct 31, 9:26pm
Carburettor? What are they?

peja, Oct 31, 9:29pm
In addition most modern cars have the fuel pump in the tank, and it is colled by the remaining fuel. So if you run your car below a quarter tank or with the fuel light on a lot the pump will run hot and gum up. I never let the fuel light come on and usually dont let it get much below a quarter full

paul861, Oct 31, 9:30pm
I thought the fuel pickup was constantly sucking from the bottom of the tank?

shakespeare6, Oct 31, 10:05pm
Yep me too, every tank I've opened and every fuel pump I've pulled out sucked from the bottem , even the water sits on the bottem, it's the first thing you suck up.
May by op had stuff floating in the top

franc123, Oct 31, 10:16pm
The biggest killer of in tank pumps is water contamination and lack of filter changes by negligent out of sight out of mind owners, this naturally stresses both the pump and its supply circuit. Running them dry obviously doesn't help but unless a hole develops in the fine mesh sock filter through slight movement of the pump making it chafe on the bottom of the tank, ingress of large particles of debris isn't likely.

saki, Oct 31, 10:38pm
Must be that the gunk floats and when the tank is empty it ends up in the pick up (not)

r.g.nixon, Oct 31, 10:54pm
I thought gunk was the problem, but now I think water was the main problem. The fuel filter was rusty. Changing that didn't fix the problem, so the next step was the carb and fuel tank. That's when they found about a litre or more of water. My car ran very jerkily, and kept stalling, on a diet of watery petrol.

upnorth, Nov 1, 1:01am
The AA mechanic said the fault was "just crap in the carburettor".

To which the blonde asked "How often?"

elect70, Nov 1, 1:35am
Funny tho when I bought my rangie it had been sitting for 7 years with less than 1/4 tank petrol . Drained it out clean as no water no gunk & even used the petrol in my lawnmower no problem

franc123, Nov 1, 2:45am
Check your filler cap seal.

marte, Nov 2, 11:53am
Is there alcohol in our NZ fuel?

1) Adding meths to a 1/4 - 1/8 tank of fuel should mix water with petrol and get rid of it.
Then when the tanks nearly empty, fill it full.

2) But leaving Meths in the tanks petrol for a long time is a bad idea as it will suck up water from the air into the petrol.
This will cause rust in the tank over time.

3) Adding a small (two nips of) amount of Acetone to a tank of petrol will raise the Octane rating cheaply and gives you a better burning petrol.

4) Adding Acetone to your petrol may ruin fuel hoses and fittings.

Whats your thoughts on these ideas?

I found out by accident that some Acetone made my offroad motorbike go a LOT better. Actually a LOT LOT better, and faster, and far better pickup, and cleaner, and it even sounded better.
A 'snap' rather than a 'pop' with every engine pulse.

bill1451, Nov 3, 4:51am
Would adding acetone raise the compression ratio, putting more strain on bearings, etc,

sr2, Nov 28, 4:10pm
No, the compression ratio is static.