Hi

My car has recently started to read the fuel quantity in the tank incorrectly due to what I suspect is the disintegration of my fuel float. I'm guessing it is down to the methanol usage on my car but what I really want to know is what my replacement options are? Is there an aftermarket float that other methanol runners have been using?

Cheers

 

bttt - anyone?

 

No idea on how to correct it but I know you're not alone. Higgy on SIDC also has ther same problem on his bugeye since he started using methanol.

A big jerrycan seems to be the solution.

 

What % Meth you using Des?? how many miles or litres of meth you been through?

never had a problem on my car.. <touches wood>

Simon

 

Hi Colin.

Hmmm... some more digging required then. I did find aftermarket sender units etc with their own guages but didnt want to go this far. It's (probably) being looked at this weekend so perhaps a solution can be found.

Cheers

 

Hi Simon

Running 10% meth with V-power. Mark (Lateral) who supplied the injectors did say that a few of the big bhp cars seemed to have experienced the issue running higher percentages of meth. Seems I was just unlucky (referring to the other thread on meth not this one).

In terms of distance travelled not much (just got through 50 litres of meth). However it may be my filling method which involves running the car to near empty, stopping at the petrol station, pouring in the meth (exposing the float to high concentrations) and then adding the petrol to mix it all up.

Cheers

 

that is how I have filled mine..

Simon

 

Sorry to hijack the thread but I have to ask; why do you use methanol (genuine question) ?

Darren

 

quick answer.. as an octane booster.. so can be either used for safety margin or mapped for and therefore giving more power.

Simon

 

If mapped for, what gains can methonal give?

 

Around 20+bhp.. depends on setup

Simon

 

Des, out of interest is it under or over reading?

 

Hi Colin

It's telling me I have plenty in the tank but the emergency fuel light is on. I believe the earlier cars only had one system that reported fuel level (hence the fact that I have heard of people sitting at the side of the road because they thought they still had fuel in the tank) but that the later classics used two (explaining why my fuel light came on but the guage is indicating loads of fuel). I noticed the problem becoming worse after successive refuels where the guage just read higher and higher.

Simon - you have probably put this up somewhere before, but what model car do you have? Just wondering if there is a difference in the floats used (seeing as you havent had any issues).

Cheers

 

96..

slightly strange though Des.. it is a float.. ie. it floats when there is fuel in the tank.. so why would it be floating when there is no fuel in the tank if the methonal ate it??

Simon

 

Hence my question about whether it was over or under reading.

On Higgy's it saying there is up to a quarter of a tank when he is on vapours. I had a 50 mile round trip to get him a jerry can when he ran out in the middle of nowhere.

I mentioned to him that if the float had rotted away it would drop and give the impression of less fuel, not more. Did you change your fuel pump at the same time you started using meth and have maybe bent the arm the float is on. It's very easy to do. If it'll help you figure it out I can take a pic of a fuel float and sender setup and post it up.

 

Is it less expensive than normal octane booster then, say Millars or similar ?

Darren

 

It works out a roughly the same price as running on v power alone.

When you put 50 ltrs of v power in and then add a few ml's of booster you have to pay for both. When you run with a 10% meth mix you only put in 45 ltrs of v power and then 5 ltrs of methanol (which is cheaper than v power) so it can actually work out cheaper to run your car.

 

Hi Simon

Good point. I didnt get to peek in the fuel tank this weekend as planned, but might find some time during the week.

Cheers

 

Hi Colin

The fuel pump was changed in round one of mods some 3-4 years ago. I dont remember going in the tank for anything (nor do I remember a reason for my engine builder to do so). Doesnt rule it out though...

Did Higgy find the answer to his issue i.e. was it a bent arm?

Cheers

 

As per Playsatans comments... Worth pointing out it also makes the car run a bit leaner. If you get a remap and the car is already running quite lean, you may encounter some issues. Best to check with your mapper before adding it.

 

Don't like the sound of this, have many people had these problems??

My car is being Mapped for 10% Methanol in 2 weeks. I've already bought 60 litres of the stuff.

 

Dean i have so far used 70 litres of methanol and i have not a single problem with my car.

Banny

 

thats good to hear.

Damm you must do some miles in your car, you haven't been running it long, it would take me about 8 months to use 70 litres at 10%

 

Not yet but he is on first name terms with all the local RAC men.

If he figures it out I'll pass it on.

 

Fuel level sensors are commonly either a potentiometer (3-wire) or a variable resistor (2-wire) operated by the float arm. The resistor is usually formed by thick film printing of a resistive ink and a great deal of work is involved ensuring compatibility of the resistor material with various fuel combinations. It is quite possible that the methanol is modifying the resistor value either by absorption or even partially dissolving the ink thereby giving a false reading.

Matt