View Full Version : Fuel Pump Noise (too much)

Barry Davolls
03-06-03, 07:33 PM
I have recently fitted a new fuel pump.
It is a high pressure Holley pump in my case running at 50 psi.
Initially, in the garage & during setting up, the pump was very quiet.
Having now run the car on the road for perhaps one hour, the pump has become quite loud although stills works fine.
Gravity feed is good, filters are clear etc etc.
Can anyone shed any light as to why my unit should go from nice & quiet to loud in the space of a few miles. Is it possible that they are factory lubricated to cater for priming & otherwise dry running during setting up & this has now dissolved?
Should I be worried?


Barry Davolls
13-06-03, 09:17 PM
For anyone thatís interested:
Car was being worked on for 3 months prior to running. During that time water in the petrol (probably a bad tank of fuel) gave rise to bacteria feeding on the carbon in the fuel. Net result was a yeast like substance that near fully blocked both filters & gummed up both fuel pumps. Fuel could get through to start with & within a few miles the yeast like material began to suffocate the pumps & hence made a louder noise.
I did not realise how common a problem this is with cars that are used infrequently (ie not at all during winter in my case).
Learnt the lesson, will add dry tank chemicals during winter in future.


13-06-03, 10:38 PM
Thanks for the update, what are "dry tank chemicals"?

Barry Davolls
14-06-03, 07:13 AM
Dry Tank is made by Wynns (others make similar products).
It is a fuel additive that mixes with water & fuel.
Once mixed, the bacteria in the water can no longer feed on
the fuel & thus problem solved.

17-06-03, 04:42 PM
mmmm intresting that, didnt know that sort of stuff happened, I presumed that the petrol would be a nasty inhospitable place to live, shows how wrong ya can be...