Fuel Tank Issue
07-08-2022, 10:02 AM
#1
Junior Member
Thread Starter
Fuel Tank Issue
Hello All,
I have a 1995 C280 and have problem with water in my fuel tank from being attracted from crappy ethanol fuel that is killing my electric fuel pump over and over again. I have pulled the hose from the tank to the fuel pump off and drained all I could get out of the tank and added a few gallons of fresh Non-ethanol fuel and drained it again. The problem I am guessing is that the tank is a saddle type tank with a left and a right side. I am draining from the right side where the fuel pump is connected to it, but apparently water is trapped in the left side and after installing a new fuel pump (due to seizure from water) and then running the car, the pump is circulating fuel to the engine and back to the tank again and moving residual water from the left side of the tank through the system and seizing the pump again. This car sits for weeks at a time or longer without use. I have now put 4 electric fuel pumps in the car and I'm over it! I can't keep doing this. My question is how do you drain the left side of the tank? I do not see any hose connection or removable fitting from underneath the car.
Thanks
I have a 1995 C280 and have problem with water in my fuel tank from being attracted from crappy ethanol fuel that is killing my electric fuel pump over and over again. I have pulled the hose from the tank to the fuel pump off and drained all I could get out of the tank and added a few gallons of fresh Non-ethanol fuel and drained it again. The problem I am guessing is that the tank is a saddle type tank with a left and a right side. I am draining from the right side where the fuel pump is connected to it, but apparently water is trapped in the left side and after installing a new fuel pump (due to seizure from water) and then running the car, the pump is circulating fuel to the engine and back to the tank again and moving residual water from the left side of the tank through the system and seizing the pump again. This car sits for weeks at a time or longer without use. I have now put 4 electric fuel pumps in the car and I'm over it! I can't keep doing this. My question is how do you drain the left side of the tank? I do not see any hose connection or removable fitting from underneath the car.
Thanks
07-09-2022, 12:45 PM
#2
Member
Not sure why you're having problems with water, fuel with ethanol in it should be absorbing the water. Here's a link with info, have you tried another brand of fuel, or another location? Curious that you're getting so much water.
https://www.cars.com/articles/do-i-n...1420682864409/
I can't remember the last time i've had a water problem, even in cars that have sat a while - even in winter down to -20° C.
https://www.cars.com/articles/do-i-n...1420682864409/
I can't remember the last time i've had a water problem, even in cars that have sat a while - even in winter down to -20° C.
07-09-2022, 03:22 PM
#3
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MY'14 W212 M276 3.5NA @60kMi
water in tank
FOUR fuel pumps, I can see this being extremely upsetting.
The only way I know to prevent fuel tank condensation from accumulating is by keeping the tank full.
Sorry I don't know the exact type of fuel system on your chassis.
The only way I know to prevent fuel tank condensation from accumulating is by keeping the tank full.
Sorry I don't know the exact type of fuel system on your chassis.
07-10-2022, 08:39 PM
#4
Junior Member
Thread Starter
Thank you Steve but I do not need info on Fuel anti freeze. That is not my problem and does not answer my question. I am trying to figure out how to drain the left side of a saddle tank? Ethanol fuel attracts moisture out of the air. I live in south Florida where it is extremely humid. If you burn your tank up and refill every week or two you are ok. If you leave it sit in your tank for a month or two, you will have water in your tank.
07-10-2022, 11:02 PM
#5
Member
Ahh, got it. We use it up here to get the water out of the tank in winter. It ends up freezing in gas lines, resulting in a tow to a warm garage to thaw and then mix some ethanol in to absorb the water. Most gas here now contains it for winter (it never used to) to avoid this problem.
Someone mentioned (once the water's removed) to keep a full tank. We do the same in winter to reduce the amount of moisture condensing in the top of the tank.
Far as physical removal goes (short of tank removal and pouring it out and separating it), not sure if there's a way to snake a siphon into the other part of the tank....
Someone mentioned (once the water's removed) to keep a full tank. We do the same in winter to reduce the amount of moisture condensing in the top of the tank.
Far as physical removal goes (short of tank removal and pouring it out and separating it), not sure if there's a way to snake a siphon into the other part of the tank....
