31 Jul 2012, 10:53
...Just as an add to this thread, and for some addtional information, I had this noisy vibrating fuel pump issue on Wednesday last week for the first time - I didn't know what was causing it. It was quite alarming at the time.
I was a little worried about this, but the next day the problem seemed to have gone again. Only after talking to Stunned_Monkey and Rich_H on the following Sunday did I learn about what this was.
So for prosperity, here's a scenario to explain, in case anyone gets something similar in the future...
Wednesday was a really hot day, really HOT. After about 2.5hrs of driving, towards the last 40mins of the journey, traffic slowed, and this resulted in eeking the last few miles at slow pace.
With the heat from the cooling water system surrounding the fuel tank and acting as a radiator, and then finally the cooling fans kicking in, resulting in hot air being blown on to the fuel tank too, the fuel temperature got VERY hot!
This in turn, softens the rubber hosing coming off the bottom of the fuel pump (The funny "?" shaped hose). With the suction of the hot fuel through the softened uptake hose, the walls of the hose collapse inwards, essentially trying to block the supply of fuel to the pump.
The pump then struggles to continue to pull fuel up out of the tank, causing it to work harder and louder.
This increased noise is then emphisised as it's sitting inside the tank, which acts like a drum, and amplifies the noise, making it sound awful, and quite disturbing if you don't know what it is. You can actually feel this vibration through the gear stick! (on a manual car at least)
It's the same vibration you feel when you turn the key on the ignition to stage 2, which results in the fuel pump priming itself briefly to prepare for the engine requiring fuel at the follow up turn of the key to position 3)
This increased stress on the pump, exhibited by the noise, over time and exposure, will shorten the lifespan of the pump. It will eventually burn it out (increased stress, means more heat from the motor, meaning hardware eventually breaks down).
There are 3 solutions:
1. As stated above, the "CoilZilla" (Unofficial name) approach mentioned by RichH which involves threading a coil of stiffish wire down the pipe (removing it from the tank first of course) to stop the pipe collapsing. (Make sure that the coil of wire doesn't pretrude past the end of the pipe which connects on to the pump - obvious, but worth mentioning. Also, don't leave the coil of wire in such a way that it may puncture the hose, especially when it softens, or of course, during application of it inside when its detached from the car)
2. Put nice new cool fuel in the tank at a service station
3. Stop the engine and go away and have a cup of tea to give it time to let the fuel cool down inside the tank again (meaning the hose pops out to normal shape again)
It's quite a rare circumstance to get this noise - it requires quite extreme conditions (or a particularly old fuel hose inside the tank to make it happen more often - at this point, replace the hose to make sure it doesn't split, meaning it could start drawing in fuel further up than expected, meaning it could start drawing air rather than fuel, if the level in the tank drops below where a split may be)
Other than this, it shouldn't happen to many people that often.
I was a little worried about this, but the next day the problem seemed to have gone again. Only after talking to Stunned_Monkey and Rich_H on the following Sunday did I learn about what this was.
So for prosperity, here's a scenario to explain, in case anyone gets something similar in the future...
Wednesday was a really hot day, really HOT. After about 2.5hrs of driving, towards the last 40mins of the journey, traffic slowed, and this resulted in eeking the last few miles at slow pace.
With the heat from the cooling water system surrounding the fuel tank and acting as a radiator, and then finally the cooling fans kicking in, resulting in hot air being blown on to the fuel tank too, the fuel temperature got VERY hot!
This in turn, softens the rubber hosing coming off the bottom of the fuel pump (The funny "?" shaped hose). With the suction of the hot fuel through the softened uptake hose, the walls of the hose collapse inwards, essentially trying to block the supply of fuel to the pump.
The pump then struggles to continue to pull fuel up out of the tank, causing it to work harder and louder.
This increased noise is then emphisised as it's sitting inside the tank, which acts like a drum, and amplifies the noise, making it sound awful, and quite disturbing if you don't know what it is. You can actually feel this vibration through the gear stick! (on a manual car at least)
It's the same vibration you feel when you turn the key on the ignition to stage 2, which results in the fuel pump priming itself briefly to prepare for the engine requiring fuel at the follow up turn of the key to position 3)
This increased stress on the pump, exhibited by the noise, over time and exposure, will shorten the lifespan of the pump. It will eventually burn it out (increased stress, means more heat from the motor, meaning hardware eventually breaks down).
There are 3 solutions:
1. As stated above, the "CoilZilla" (Unofficial name) approach mentioned by RichH which involves threading a coil of stiffish wire down the pipe (removing it from the tank first of course) to stop the pipe collapsing. (Make sure that the coil of wire doesn't pretrude past the end of the pipe which connects on to the pump - obvious, but worth mentioning. Also, don't leave the coil of wire in such a way that it may puncture the hose, especially when it softens, or of course, during application of it inside when its detached from the car)
2. Put nice new cool fuel in the tank at a service station
3. Stop the engine and go away and have a cup of tea to give it time to let the fuel cool down inside the tank again (meaning the hose pops out to normal shape again)
It's quite a rare circumstance to get this noise - it requires quite extreme conditions (or a particularly old fuel hose inside the tank to make it happen more often - at this point, replace the hose to make sure it doesn't split, meaning it could start drawing in fuel further up than expected, meaning it could start drawing air rather than fuel, if the level in the tank drops below where a split may be)
Other than this, it shouldn't happen to many people that often.
Rissy
(Forum Member 288)
(DOC Member 663)
May 1981 vin#1458 "LEX"
Grey, Flapped, Black
Chassis: #1073
Engine: #2839
Main Car(s):
2005 BMW M3 in Velvet Blue
2010 Honda Civic Type R in Sapphire Blue (1 of 115 made)
(Forum Member 288)
(DOC Member 663)
May 1981 vin#1458 "LEX"
Grey, Flapped, Black
Chassis: #1073
Engine: #2839
Main Car(s):
2005 BMW M3 in Velvet Blue
2010 Honda Civic Type R in Sapphire Blue (1 of 115 made)
