News:

         
Welcome to FJowners.com


It is the members who make this best place for FJ related content on the internet.

Main Menu

1989 FJ1200 - fuel cascade on start - Fuel Pump or Relay?

Started by pdbnorth12, June 10, 2019, 02:55:45 PM

Previous topic - Next topic

pdbnorth12

I'm having what I assume might be a relatively common issue - when I turn the ignition on and press the start button, the bike tries to empty the fuel tank onto the garage floor, and stops when the ignition is turned off. I've been digging through posts, but haven't found if that's symptomatic of a faulty fuel pump, or if it's the Omron G8D-04Y fuel pump relay.

Given their respective prices, I have no issue replacing the fuel pump at the same time as the relay (assuming I can find one), but if it's the fuel pump, I'd leave that relay alone. I'm thinking that the fuel pump could be replaced and then checked, but I'd love to get better knowledge of the root cause if possible.

Thanks,

PDB

1989 FJ1200

racerrad8

Quote from: pdbnorth12 on June 10, 2019, 02:55:45 PM
I'm having what I assume might be a relatively common issue - when I turn the ignition on and press the start button, the bike tries to empty the fuel tank onto the garage floor, and stops when the ignition is turned off. I've been digging through posts, but haven't found if that's symptomatic of a faulty fuel pump, or if it's the Omron G8D-04Y fuel pump relay.

Given their respective prices, I have no issue replacing the fuel pump at the same time as the relay (assuming I can find one), but if it's the fuel pump, I'd leave that relay alone. I'm thinking that the fuel pump could be replaced and then checked, but I'd love to get better knowledge of the root cause if possible.

Thanks,

PDB

1989 FJ1200

Not sure I understand the issue.

Is your carbs overflowing fuel?
Does the fuel pump shut off after a 2~5 seconds?
Is the fuel pump properly wired using the relay?

If you need a new pump, we have the lowest price on Yamaha fuel pumps: http://www.rpmracingca.com/proddetail.asp?prod=YamFPump

Randy - RPM
Randy - RPM

red

Quote from: pdbnorth12 on June 10, 2019, 02:55:45 PM
I'm having what I assume might be a relatively common issue - when I turn the ignition on and press the start button, the bike tries to empty the fuel tank onto the garage floor, and stops when the ignition is turned off. I've been digging through posts, but haven't found if that's symptomatic of a faulty fuel pump, or if it's the Omron G8D-04Y fuel pump relay.  Thanks,
PDB  1989 FJ1200
PDB,

Where is the fuel coming from, on the bike?  The carb float bowls should cut off the fuel when full, even if the pump still runs.  If the fuel is coming from the carb(s), it may be getting into the engine oil.  If the oil level has increased, or smells like gasoline, DO NOT run the engine until you repair the problem and change out the compromised engine oil.  An aftermarket fuel pump may be able to overpower the carb floats, due to excess pressure and flow.  I would doubt that the relay causes your problem.

Then again, you may simply have a cracked fuel line, or a bad fuel line clamp.  Let us know what you find.
Cheers,
Red

P.S. Life is too short, and health is too valuable, to ride on cheap parade-duty tires.

Pat Conlon

Quote from: pdbnorth12 on June 10, 2019, 02:55:45 PM
.....but haven't found if that's symptomatic of a faulty fuel pump, or if it's the Omron G8D-04Y fuel pump relay.

It's neither...you have 1) a stuck carb float, 2) debris in your float needle seat(s) or 3) very commonly dried knakered float needle seat o rings.

Read all about it in the Carb Files: http://www.fjowners.com/index.php?topic=46.0

Cheers
1) Free Owners Manual download: https://tinyurl.com/fmsz7hk9
2) Don't store your FJ with E10 fuel https://tinyurl.com/3cjrfct5
3) Replace your old stock rubber brake lines.
4) Important items for the '84-87 FJ's:
Safety wire: https://tinyurl.com/99zp8ufh
Fuel line: https://tinyurl.com/bdff9bf3