No Flow

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peterz84
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Joined: Fri Sep 18, 2009 5:16 pm

No Flow

Post by peterz84 »

Hey people, it's the new guy. Just posted in the "welcome/Intro" section and like I said, here come the questions. I got the 400 into the garage and tried firing it up. Nothing, it turns over but wont light up. It does have good spark, thats the first thing I checked. Next I went to see if it had fuel flow, it doesn't. I unpluged the pump from the harness and jumped it straight to the battery and the fuel shot out like a rocket from the unplugged outlet line. The pump does pump jumped over but not when plugged back into the harness. Is there a pressure relay that tells the pump to shut off at a given pressure? I drained the carbs completely and still no flow when I crank it over. The pump does not run the usual 5 second "prime" when the key is turned. Any Ideas?

Thanks Guys
Pete
Rz350, several
91 Rgv250 Vj22 SP
94 Nsr250 Mc28
88 FZR400
yamaha_george
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Location: west london UK

Re: No Flow

Post by yamaha_george »

peterz84 wrote:Hey people, it's the new guy. Just posted in the "welcome/Intro" section and like I said, here come the questions. I got the 400 into the garage and tried firing it up. Nothing, it turns over but wont light up. It does have good spark, thats the first thing I checked. Next I went to see if it had fuel flow, it doesn't. I unpluged the pump from the harness and jumped it straight to the battery and the fuel shot out like a rocket from the unplugged outlet line. The pump does pump jumped over but not when plugged back into the harness. Is there a pressure relay that tells the pump to shut off at a given pressure? I drained the carbs completely and still no flow when I crank it over. The pump does not run the usual 5 second "prime" when the key is turned. Any Ideas?

Thanks Guys
Pete
Pete,
first off welcome aboard.
If you by passed the standard wiring to the pump and it works then that shows that the wiring sequence to the pump is faulty.
If you look in the WIKI section there is a wiring diagram for the FZR (they are the same in the fuel pump wiring no matter what size or year..)

Track the wiring see if it goes any where thro a fuse, or the rh switch (well known for collecting dirt and causing all sorts of non-sense.
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mrfreeze5
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Re: No Flow

Post by mrfreeze5 »

Check your main relay, its the likely culprit. It is what tells the fuel pump to turn on and off. You should hear it click when you turn the stop switch on the right bar to ON. It should click, then the pump comes on. It will click again and the pump will stop(under normal circumstances).
peterz84
Site Newbie
Posts: 6
Joined: Fri Sep 18, 2009 5:16 pm

Re: No Flow

Post by peterz84 »

Thanks Guys, checked the switch, it was fine. Swapped out the relay and bingo, that was it, I have gas flow!! Still cant get it to fire up. Took off carbs and cleaned them thoroughly, still a no go. Anything else I should look for. Keep in mind this bike has been sitting for quite some time. There is an electrical part on the right side of the battery mounted to the outside of the subframe that looks a little questionable, could this be my problem?

Thanks Again
Pete
Rz350, several
91 Rgv250 Vj22 SP
94 Nsr250 Mc28
88 FZR400
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mrfreeze5
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Re: No Flow

Post by mrfreeze5 »

Have you verified for sure that you have spark?
peterz84
Site Newbie
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Joined: Fri Sep 18, 2009 5:16 pm

Re: No Flow

Post by peterz84 »

Yes, spark on all 4 cylinders, pulled the plugs out 1 at a time and checked, seems to be ok.

Thanks
Pete
Rz350, several
91 Rgv250 Vj22 SP
94 Nsr250 Mc28
88 FZR400
yamaha_george
5000+ Posts
5000+ Posts
Posts: 5853
Joined: Fri May 09, 2008 8:46 am
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Re: No Flow

Post by yamaha_george »

peterz84 wrote:Yes, spark on all 4 cylinders, pulled the plugs out 1 at a time and checked, seems to be ok.

Thanks
Pete
P,
the spark may look good out of the engine, but...............
Have you checked the battery lately FZR's are VERY fussy about the starting current available to them. and the old style Voltage is always a "usual suspect" for keeping the battery in good shape.

I also seem to remember there is a trouble shooting "flow" diagram in the WIKI written by one of our own electrical wizards you might find that beneficial in your quest for a working bike
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