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This link is automotive, but may be of interest re different type of submerged pumps and common failure causes.
https://premierautotrade.com.au/news/ele...-pumps.php
Note the potential issues from:
Contaminated fuel
Poor electrical connections (higher resistance lowers voltage and causes higher current draw)
Failed/failing check valves
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SD, I like that link, educative
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I looked at that link, and I didn't find info relative to our CB1100s, or to most modern Japanese fuel injectted motorcycles, as it refers to pumps for carbureted engines, throttle body injection, and primer pumps, all automotive applications.
The fuel pressure is usually about 50 psi, or 3.4 - 3.5 bar, whether from a regulated nternal pump, or an external one, as found on some cruisers and ATVs.
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This is the section I thought may be of interest, contaminated fuel and electrical connections:
Typical Electric fuel pump problems.
Whether the fuel pump is in the tank or externally, many faults created are similar.
Faults caused to the fuel pumps by contaminated fuel:
Noisy fuel pump operation. (possibly including lower fuel pump RPM)
Fuel pump locked (not spinning).
Reduced pressure and fuel flow.
Note: Contaminated fuel generally results in a “Not approved” claim when a fuel pump is returned for a warranty claim.
Faults caused by poor electrical connections, power supply and circuitry.
Poor fuel pump connections either in tank or external generally result in intermittent loss of fuel pressure and stalling.
Faulty relays also create an intermittent or continuous loss of fuel pressure and stalling or no start.
Internal electrical faults in the fuel pump may cause lower pump RPM with reduced engine power or a no start condition if fault is excessive.
ECU faults generally result in a no start condition.
Fuel pump mechanical faults:
Check valves used to prevent fuel draining back to the tank when the engine is switched off can fail causing extended cranking period before engine restarts. A pressure gauge can quickly test for this condition by checking for losses in residual pressure when the engine is switched off after a period of running. A leaking check valve has no effect on normal fuel pressure during operation.
