Hi,
I recently serviced my 2001 California Stone which included replacing the UFI 3150400 fuel filter.
I was unable to source the same brand so ordered a listed equivalent Bosch F5021.
After removing the UFI filter and installing the screw in pipe connections into the Bosch unit I found that it was a slightly smaller diameter. I therefore used a small slice of rubber as packing in the retaining clamp and fitted the filter to the bike.
Following the reinstallation of the fuel tank etc I turned on the ignition three or four times to fill the new filter and prime the system. This was accompanied by various squeaks, squeals and whirring fuel pump noises.
I then started the engine.
I was surprised at the volume of the fuel pump. I am usually aware of it only when first turning on the ignition. To be able to hear it even with the engine running through my Lanfranconi Riservato Competitzioni mufflers made me wonder if I was about to experience a fuel pump failure. I have now ridden sixty miles with no ill effects but the pump is still noisier than it was before changing the filter.
I did a search through an english Moto Guzzi forum and found an old post from somebody who had experienced the same problem after replacing their UFI fuel filter with an un-named german alternative, of slightly smaller diameter. After a few suggestions from other members he claimed that he had found it to be caused by a sticky fuel tap!
I think that the only way that a fuel tap could be responsible would be by restricting the flow to the pump, so that it was cavitating and/or pumping air. I have run my bike at full throttle and there is no evidence of fuel starvation. Rapping the body of the fuel tap with a spanner makes no difference to the pump noise.
Before I go to the trouble of refitting the original filter and doing a flow test through the fuel tap, I wondered if anybody was aware of a problem of this nature if an incorrect fuel filter is used.
Thank you.
I recently serviced my 2001 California Stone which included replacing the UFI 3150400 fuel filter.
I was unable to source the same brand so ordered a listed equivalent Bosch F5021.
After removing the UFI filter and installing the screw in pipe connections into the Bosch unit I found that it was a slightly smaller diameter. I therefore used a small slice of rubber as packing in the retaining clamp and fitted the filter to the bike.
Following the reinstallation of the fuel tank etc I turned on the ignition three or four times to fill the new filter and prime the system. This was accompanied by various squeaks, squeals and whirring fuel pump noises.
I then started the engine.
I was surprised at the volume of the fuel pump. I am usually aware of it only when first turning on the ignition. To be able to hear it even with the engine running through my Lanfranconi Riservato Competitzioni mufflers made me wonder if I was about to experience a fuel pump failure. I have now ridden sixty miles with no ill effects but the pump is still noisier than it was before changing the filter.
I did a search through an english Moto Guzzi forum and found an old post from somebody who had experienced the same problem after replacing their UFI fuel filter with an un-named german alternative, of slightly smaller diameter. After a few suggestions from other members he claimed that he had found it to be caused by a sticky fuel tap!
I think that the only way that a fuel tap could be responsible would be by restricting the flow to the pump, so that it was cavitating and/or pumping air. I have run my bike at full throttle and there is no evidence of fuel starvation. Rapping the body of the fuel tap with a spanner makes no difference to the pump noise.
Before I go to the trouble of refitting the original filter and doing a flow test through the fuel tap, I wondered if anybody was aware of a problem of this nature if an incorrect fuel filter is used.
Thank you.
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