Gas tank swap?

[Paul1965]

I also have concerns about leaking.  Steel would be a better choice for strength on the threads.  Having said that, I have built lots of fuel tanks from aluminum, many of them with fuel gauge sending units that have a bolt flange attaching it to the tank. I usually tack weld a 1/4"plate on the inside of the tank, as many of them are only 1/8"thick, and drill and tap the six small bolt holes.  This isn't a huge concern for leakage considering it's located on the top of the tank.  On a motorcycle tank, the petcock MUST be sealed...

If you do use aluminum, ensure you follow the tap drill size chart to make sure you have the proper thread depth.

Derek

Thanks for the input Derek. I did end up getting a length of 1/4" steel stock instead of aluminum, and I think I've come up with an even better idea. I'm going to try to open up the OE 90 petcock as much as I can, then make an adapter from the steel stock that will bolt up to the OE 84 petcock.  That adapter will have nothing more than a 3/8 NPT nipple threaded into it, with a length of hose attaching it to the 90 petcock. Then all I have to do is secure the 84 petcock to the bike and I think I'll be good to go. At least that's what I hope lol!

[Paul1965]

Well after all the flip flopping I've done, I decided to heed the advice of you guru's and go with a fuel pump setup. I found a good deal on a Facet 40178 pump that should work for what I need. Thanks again to everyone for all the great advice you've given; I'm glad that the majority of the members here are sensible people that are willing to help one another out.

[Paul1965]

Just wanted to update this thread and let everyone know that the pump and filter showed up last week and I got everything installed Saturday. It was too cold to ride the bike, but it starts and revs great, so hopefully I won't have any issues on the road. I'll go back down to the shop this weekend to tidy things up a bit with the harness I made. Thanks again to everyone for the help!

[movenon]

For those following the thread the Facet fuel pump 40178 and a Facet fuel pump 40171 are the same pump. The only difference is the "171" pump has Packard electrical connectors on the end of the wires and the "178" is just has unterminated wires.

The 40178 pump is also sold through NAPA part number 610-2403 but of course NAPA is more expensive. The "171" and "178" pumps are on-line for less than 50.00. NAPA has there pump priced at 75 - 85.00 in there stores. But if on the road you needed a 171 /178 pump then NAPA would be a player.

Both pumps check the fuel flow with power off in both directions. Positive shut off and anti siphon (check valve). The anti siphon (check valve) is not a feature needed in the FJ's, Facets definition of the check valve is to prevent fuel from draining back down into a fuel tank mounted lower than the carbs, as in a car or truck.

The fuel filter they recommend is a Purolator FEP 735 / NAPA 610-1085 / CarQuest 41506 / Partsmaster FEP 735. It is a 74 micron filter which is fairly course as filters go. A finer filter will drop the pressure to some degree.

As to if the Facet 171 / 178 pump will work out in the FJ (pressure, volume, and reliability) is a question to be answered in the real world. Paul has one on his and I will have one on mine shortly but cold weather slows that process down.

Hope this information helps anyone doing a search on Facet fuel pump.
George

[giantkiller]

Thanks George. Let us know if good in real world. When weather allows.

[fintip]

Great info at the end here. Is the idea that this pump provides a fuel pressure low enough that you could convert an ambulance FJ into a fuel pump FJ without modifying the carbs? Or did you two end up doing the carb conversion to go along with the pump and this is just a cheap pump?

Also, anyone able to point me to a thread on someone doing the early-to-late carb setup? Considering upgrading to a fuel pump setup on my FJ, trying to figure out what the price would be on that mod. Gettin' real sick of my intermittent petcock issues.

[FJmonkey]

This is a project I was hoping to experiment with. I have a fuel pump from George as well as other bits to connect it. I was first going to just hook it up to the GF carbs to see how well the floats and pins dealt with the pump pressure. Worst case scenario is you need to change out the float pin seats to the smaller diameter, adjust the floats and leave the rest alone (maybe add a fuel filter). However, there is one issue I have concerns with. The pump can be connected to an ignition switched power source. But the FP FJ's have a safety feature. With the ignition on but engine off the pump will only run a few seconds and turn off. Once the engine is running the pump is energized and fills per demand. With the ignition switched power, the pump will be energized as soon as the ignition is on, regardless if the engine is running or not. In this case, fuel could be pumped passed leaking float pins and dumping under your bike without your knowledge. Seems like a recipe for a Flaming Monkey to me.... Makes a good name for a drink though.... Flaming Cocktails 1: Flaming Monkey

[racerrad8]

...But the FP FJ's have a safety feature. With the ignition on but engine off the pump will only run a few seconds and turn off. Once the engine is running the pump is energized and fills per demand.

What, there is a built in safety feature of the fuel pump circuit that uses the CDI signal to control the pump if the engine is not running?

Randy - RPM

[FJmonkey]

...But the FP FJ's have a safety feature. With the ignition on but engine off the pump will only run a few seconds and turn off. Once the engine is running the pump is energized and fills per demand.

What, there is a built in safety feature of the fuel pump circuit that uses the CDI signal to control the pump if the engine is not running?

Randy - RPM

Perhaps I am missing something. But it seems like that is the case. On more than one occasion I witnessed a FP bike being primed by turning the key on till the pump stops clicking, then doing that several more times. I have seen this more than once to fill up empty bowls. If that is not the case, then why does the pump keep clicking after the second and following attempts if the bowls are full? If that is not the case then the ignition switched power for the pump is not an issue for the conversion from GF to FP...

[FJscott]

another way is to wire the pump through an oil pressure switch. no oil pressure, no power to the pump. easy cheesy.thats a very common method on marine engines.

Scott

[FJscott]

...But the FP FJ's have a safety feature. With the ignition on but engine off the pump will only run a few seconds and turn off. Once the engine is running the pump is energized and fills per demand.

What, there is a built in safety feature of the fuel pump circuit that uses the CDI signal to control the pump if the engine is not running?

Randy - RPM

Perhaps I am missing something. But it seems like that is the case. On more than one occasion I witnessed a FP bike being primed by turning the key on till the pump stops clicking, then doing that several more times. I have seen this more than once to fill up empty bowls. If that is not the case, then why does the pump keep clicking after the second and following attempts if the bowls are full? If that is not the case then the ignition switched power for the pump is not an issue for the conversion from GF to FP...

internal pressure switch?

[FJmonkey]

another way is to wire the pump through an oil pressure switch. no oil pressure, no power to the pump. easy cheesy.thats a very common method on marine engines.

Scott

I had not thought about it much but I like that idea. Along with an out of sight momentary "pump on" button to prime empty bowls for the rare ocassion. 

[racerrad8]

Perhaps I am missing something. But it seems like that is the case. On more than one occasion I witnessed a FP bike being primed by turning the key on till the pump stops clicking, then doing that several more times. I have seen this more than once to fill up empty bowls. If that is not the case, then why does the pump keep clicking after the second and following attempts if the bowls are full? If that is not the case then the ignition switched power for the pump is not an issue for the conversion from GF to FP...

No, you are correct...

internal pressure switch?

No, it is a safety feature Yamaha uses incorporating the CDI signal. If there is no CDI spark signal then the pump shuts down after 3-5 seconds.

This is the most important in case of a crash where the engine is no longer running but the ignition is still on to prevent fuel from being just pump through the carbs as the bike lays on its side.

So, if you want to convert a gravity bike to fuel pump the only other option would be to use a low oil pressure switch to shut the pump off when the bike is not running. There will need to be a bypass switch to prime the carbs when they are empty or if the bike has been sitting and the fuel could have evaporated.

The only problem we found with a low oil pressure switch is the FJ idle at around 3-5 lbs when warm. We tried to use them on the cars but with the engine warm & idling the oil pressure was not enough to keep the switch energized and the car would run out of fuel.

Randy - RPM

[FJscott]

that would be a good set up for a conversion. I've been reluctant to post my findings on a trial pump I installed on my 92 until enough miles were logged in but I found another fuel pump option. I was in a bind and needed a fuel pump in a hurry. My small town doesn't have a Napa so I couldn't use the pump George has but I took the specs from the Napa pump and found one at Car Quest. It's 30gph @ 3.5-5.5psi it has a ball check in outlet to stop fuel when off. It even fits in the stock FJ pump bracket. It is a rotary vane type pump that comes with a lifetime warranty all for $65. I've logged about 700 miles on it without issues.

Scott

[FJmonkey]

A vacuum switch would work, no vacuum, no pump... Same as the petcock fuel control.