Motorcycle Repair: Help me please, fuel pressure regulator, kawasaki gpz

Question
would a clogged fuel injector cause the fuel pump to shutdown? I really don't think its a fuel restiction problem. I s there any other thing [electrical] that might be shutting down the pump? I did the complete test on the relay & its proves to be good.  thanks again, dam I'm baffeled.
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Followup To

Question -
I have 1984 kawasaki GPZ 1100. I seem to be having trouble with my fuel pump, The bike would run for a few minutes, then all of a sudden I would lose fuel pressure & stall. Then I disconnected pump wire harness & hooked direct to the battery. the pump hummed but no fuel. Then I removed the pump & hooked it up to power & suddenly it started to pump fuel. Could this pump be defective? I have under 5000 mi. on this bike. The bike does sit a lot without being started. I also have an adjustable fuel pressure  regulator from H.P. Unlimited.

Answer -
Hi Joe,

I suspect fuel has varnished throughout the fuel system and may be obstructing passageways and injectors. If so, the system will need thoroughly cleaned and may need parts replaced to restore proper performance.

Review the tech file below for intel about fuel. Disregard the parts about carburetors.

Respectfully,
Mark Shively




Bad Gas
By Mark Shively

Gasoline goes bad with time and in as little as 3-4 weeks. This effect is known as varnishing. Jets and passageways within carbs become obstructed when varnishing occurs.

Liquid gasoline changes chemically into a gel like substance. Advanced stages of varnishing results with the solid gel changing into a crystal powder substance. Interior carb surfaces are etched in the process and may require carb replacement.

The choke and pilot circuits with most motorcycle carburetors share passageways. When pilot jets become obstructed, the choke circuit compensates and allows engine to start and idle with choke, but stalls without choke.

Review carburetor cleaning information below. View microfiche parts, check part prices, and order service (repair) manuals here: www.bikebandit.com  

Answer
Joe,

It's not likely that a clogged injector would cause fuel pump failure. Another chronic problem is supposed to be the associated fuel system sensors.

It sounds as if the fuel pump has an intermittent problem. Locating the cause or source may be difficult. It may be a defective wire, connector, relay, sensor, corrosion, or defective internal pump components.

Try and find Kawasaki's Service Manual and Supplement manuals for the 1984 GPz. These manuals have intel that Clymer and Haynes seems to lack. Kaw's manuals will have testing procedures for the FI system.

I cannot locate anything decent that would assist you in my on-line resources.

Here's a good Kaw resource:
www.oldkawman.com

Respectfully,
Mark Shively