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General Category => Modifications => Topic started by: moelarrycurly on August 02, 2016, 09:48:33 PM

Title: Converting 84 FJ to fuel pump...
Post by: moelarrycurly on August 02, 2016, 09:48:33 PM
Hello Everybody!!

  I was wondering if anyone has had issues converting to an electric fuel pump. I bought a generic relay wired everything up applied the switch and.. The fuel pump made one "pump". No obstructions.. double checked the wiring.. Is there another component I'm missing? The pump got pretty warm but never pumped. If I switch of the key and then turn it back on-It pumps once....

Scratching my head here.
Thanks
Jason
Title: Re: Converting 84 FJ to fuel pump...
Post by: Pat Conlon on August 02, 2016, 10:14:59 PM
The fuel pump can't pump if it has no fuel....did you turn your petcock on to (P) prime position?
Title: Re: Converting 84 FJ to fuel pump...
Post by: red on August 02, 2016, 10:24:52 PM
Quote from: moelarrycurly on August 02, 2016, 09:48:33 PMHello Everybody!!
  I was wondering if anyone has had issues converting to an electric fuel pump. I bought a generic relay wired everything up applied the switch and.. The fuel pump made one "pump". No obstructions.. double checked the wiring.. Is there another component I'm missing? The pump got pretty warm but never pumped. If I switch of the key and then turn it back on-It pumps once.... Scratching my head here.  Thanks
Jason
Jason,

What pump did you get?  If you disconnect the fuel line from the carbs, does the fuel pump work continuously, as it should?  Once the fuel pressure is built up, any displacement-type fuel pump should quit.  The heat issue may be a problem, too.  The OEM fuel pump for the later model FJs costs a fortune, but Randy at RPM has a good alternative pump.

Even with the correct fuel pump, there will be an excess fuel pressure (as compared to what an FJ1100 usually has, with gravity feed).  That extra pressure may require a change in the needles, controlled by the floats.  Randy can set you up.

Cheers,
Red
Title: Re: Converting 84 FJ to fuel pump...
Post by: balky1 on August 03, 2016, 03:11:41 AM
Quote from: red on August 02, 2016, 10:24:52 PM
Quote from: moelarrycurly on August 02, 2016, 09:48:33 PMHello Everybody!!
  I was wondering if anyone has had issues converting to an electric fuel pump. I bought a generic relay wired everything up applied the switch and.. The fuel pump made one "pump". No obstructions.. double checked the wiring.. Is there another component I'm missing? The pump got pretty warm but never pumped. If I switch of the key and then turn it back on-It pumps once.... Scratching my head here.  Thanks
Jason
Jason,

What pump did you get?  If you disconnect the fuel line from the carbs, does the fuel pump work continuously, as it should?  Once the fuel pressure is built up, any displacement-type fuel pump should quit.  The heat issue may be a problem, too.  The OEM fuel pump for the later model FJs costs a fortune, but Randy at RPM has a good alternative pump.

Even with the correct fuel pump, there will be an excess fuel pressure (as compared to what an FJ1100 usually has, with gravity feed).  That extra pressure may require a change in the needles, controlled by the floats.  Randy can set you up.

Cheers,
Red

Yep, you will most probably need 1.5 needle seats for carbs. I don't know why you are troubling yourself with fuel pump installation. Rebuild the petcock, change the needle seats O-rings (or whole fittings with needles) and ride your bike. As long as it doesn't sit for long time, you'll probably have 0 probs with the petcock. Sitting is the thing that kills everything the most.
By the way, did you deal with a security issue of the pump so it doesn't pump the fuel if you fall off the bike?
Title: Re: Converting 84 FJ to fuel pump...
Post by: FJ_Hooligan on August 03, 2016, 09:03:30 AM
Is the pump designed for stall operation or continuous flow? 

The stock FJ pump will stall when the pressure is reached without overheating. 

If you use a pump that's designed for continuous flow it will overheat when it can not pump fuel to keep itself cooled.
Title: Re: Converting 84 FJ to fuel pump...
Post by: FJmonkey on August 03, 2016, 09:37:55 AM
I think Pat has called this one. On FP bikes the petcock is open or closed. On the '84 to '87 the gravity Feed (GF) uses vacuum to open and close the petcock. The '84 petcock has a PRI position that will let fuel flow till the tank is empty. Make sure your petcock is set to this position. The other issues mentioned are also worth consideration. The safety issue of the pump when the bike is tipped over. The pump pressure over filling the carbs with the larger needle seats. This has been discussed and some good ideas and solutions were posted.
Title: Re: Converting 84 FJ to fuel pump...
Post by: aviationfred on August 03, 2016, 10:45:01 AM
Quote from: balky1 on August 03, 2016, 03:11:41 AM
Quote from: red on August 02, 2016, 10:24:52 PM
Quote from: moelarrycurly on August 02, 2016, 09:48:33 PMHello Everybody!!
  I was wondering if anyone has had issues converting to an electric fuel pump. I bought a generic relay wired everything up applied the switch and.. The fuel pump made one "pump". No obstructions.. double checked the wiring.. Is there another component I'm missing? The pump got pretty warm but never pumped. If I switch of the key and then turn it back on-It pumps once.... Scratching my head here.  Thanks
Jason
Jason,

What pump did you get?  If you disconnect the fuel line from the carbs, does the fuel pump work continuously, as it should?  Once the fuel pressure is built up, any displacement-type fuel pump should quit.  The heat issue may be a problem, too.  The OEM fuel pump for the later model FJs costs a fortune, but Randy at RPM has a good alternative pump.

Even with the correct fuel pump, there will be an excess fuel pressure (as compared to what an FJ1100 usually has, with gravity feed).  That extra pressure may require a change in the needles, controlled by the floats.  Randy can set you up.

Cheers,
Red

I don't know why you are troubling yourself with fuel pump installation.



If IRC There was a displacement increase of 199cc's on this '84. I would convert to a fuel pump system to stave off fuel starvation at higher speeds/higher RPM's.

There are also used OEM fuel pumps on eBay. Here is an example. http://www.ebay.com/itm/Yamaha-Fj1200-Fuel-Pump-Fj-1200-/162154756987?hash=item25c12d3b7b:g:G5IAAOSwqBJXVHoj&vxp=mtr (http://www.ebay.com/itm/Yamaha-Fj1200-Fuel-Pump-Fj-1200-/162154756987?hash=item25c12d3b7b:g:G5IAAOSwqBJXVHoj&vxp=mtr)


Fred
Title: Re: Converting 84 FJ to fuel pump...
Post by: Pat Conlon on August 03, 2016, 01:12:55 PM
Quote from: balky1 on August 03, 2016, 03:11:41 AM
I don't know why you are troubling yourself with fuel pump installation.

So you can install a real fuel filter. Something you can not (should not) do on a gravity fed system.

Quote from: aviationfred on August 03, 2016, 10:45:01 AM
If IRC There was a displacement increase of 199cc's on this '84. I would convert to a fuel pump system to stave off fuel starvation at higher speeds/higher RPM's.

Hey Fred, currently I'm still on the oem gravity flow system on my '84 with a RPM 1380cc engine. No problems with fuel flow.
Rider incontinence yes, fuel flow no.

Quote from: FJmonkey on August 03, 2016, 09:37:55 AM
  The other issues mentioned are also worth consideration. The safety issue of the pump when the bike is tipped over.

Yes, this is important....very important. If you crash (when you crash) the bike goes one way and the rider goes another. If you are hurt, YOU DO NOT MOVE. wait for help. Immobilize the neck, etc, etc.....meanwhile your key is left in the on position and the bike is 30 yards away pumping fuel all over the road (even with the engine stalled, the fuel pump is still pumping)

Bad things will happen. :bomb:
The '89-93 fuel pump FJ's have this safety circuit. When the tach signal stops, the fuel pump stops after 3-5 seconds.

If you convert your gravity flow bike to a fuel pump you need this safety circuit.
This solution is already figured out for you. Here ya go: http://tinyurl.com/zuydbcg (http://tinyurl.com/zuydbcg)
Title: Re: Converting 84 FJ to fuel pump...
Post by: balky1 on August 03, 2016, 02:11:38 PM
Quote from: Pat Conlon on August 03, 2016, 01:12:55 PM
Quote from: balky1 on August 03, 2016, 03:11:41 AM
I don't know why you are troubling yourself with fuel pump installation.

So you can install a real fuel filter. Something you can not (should not) do on a gravity fed system.



Yes, I understand that, but I really don't see the need or the benefits for a fuel filter. If my friend managed to get 1.3 million kilometers!!! On his stock 1100 FJ. And also he never had leaking petcock nor overflowing carbs. Because he rides the bike non-stop (summer/winter). Long periods without riding kills the most things.
Title: Re: Converting 84 FJ to fuel pump...
Post by: balky1 on August 03, 2016, 02:12:58 PM
Quote from: balky1 on August 03, 2016, 02:11:38 PM
Quote from: Pat Conlon on August 03, 2016, 01:12:55 PM
Quote from: balky1 on August 03, 2016, 03:11:41 AM
I don't know why you are troubling yourself with fuel pump installation.

So you can install a real fuel filter. Something you can not (should not) do on a gravity fed system.



Yes, I understand that, but I really don't see the need or the benefits for a fuel filter. If my friend managed to get 1.3 million kilometers!!! On his stock 1100 FJ. With fuel poured in the bike from canisters in Russia, Kazakhstan, Africa, India, etc. And also he never had leaking petcock nor overflowing carbs. Because he rides the bike non-stop (summer/winter). Long periods without riding kills the most things.