Inside the fuel sender

[FJmonkey]

The tank was almost empty and I wanted to re-test the sender to verify if my "Low Fuel" light was working. Drained out the last gallon and off came the tank. Removed the float/sender unit and took the small cover off. The low fuel sensor has holes in it, top and bottom.


Top


Bottom


Inside the sender


And for any that wonder how clean the UNI dual pods work.


The filters were filthy, the carb inlets were quite clean. The filters are also now quite clean.

The sensor has clearly failed. I shorted the connector and the light works. No big deal, I watch my miles and plan my stops.

[aviationfred]

There are a couple of fuel sensors on eBay. All Years swap. http://www.partzilla.com/parts/detail/yamaha/YP-36Y-85752-03-00.html


http://www.ebay.com/itm/83-Yamaha-FJ1200-FJ-1200-Fuel-Tank-Gas-Level-Gauge-Sending-Unit-/291608382214?hash=item43e536cb06:g:Z2IAAOSw5VFWOmPG&vxp=mtr#ht_1088wt_1124

http://www.ebay.com/itm/YAMAHA-FJ1200-FJ-1200-FUEL-LEVEL-SENDER-FREE-SHIPPING-/131586363994?hash=item1ea328925a:g:gvMAAOSwd0BV2Mrg&vxp=mtr#ht_1692wt_1124


Fred

[Yamahammer1200]

Those carbs DO look clean. My bike came with a K&N filter in the air box, and it still has original pipes.
Are the pods worth it if the exhaust is stock?

[FJmonkey]

Those carbs DO look clean. My bike came with a K&N filter in the air box, and it still has original pipes.
Are the pods worth it if the exhaust is stock?

The carbs are easier to work on with the dual pods (no air box). However, consider how often we normally need to work on the carbs. I like the fact that I can clean and re-use the filters. I also like the induction sound under the seat when I twist the wrist and the 1200 cc's starts gulping air and moving me into the Kookaloo zone. If you keep the exhaust stock you should not have to re-jet, the OEM pipes are still the restriction to the air flow. Are the pods worth it? I think so, but each to their own. Some like the air box so I think it really is what you think is best for you and your FJ.

[Charlie-brm]

A few questions about the sender;

If my sender has never been removed and the gasket is then over 30 years old, what might I anticipate happening in the way of it being too rotten to re-use, and then how is the surface sealed back to the tank?

Is there anything about the sender wiper and wires that can be cleaned up to restore an accurate/stable fuel gauge reading? (Since I have one of those gauges that reads 'Full' for maybe an hour after a fill up and then drops to half or less with the usual needle bouncing.)

[racerrad8]

If my sender has never been removed and the gasket is then over 30 years old, what might I anticipate happening in the way of it being too rotten to re-use, and then how is the surface sealed back to the tank?

That is why I have that gasket in stock:

84-93 FJ Fuel Sender Unit Gasket

Randy - RPM

[FJmonkey]

If my sender has never been removed and the gasket is then over 30 years old, what might I anticipate happening in the way of it being too rotten to re-use, and then how is the surface sealed back to the tank?

In the third photo down you can see the rubber like gasket/seal sitting on top carb #2. It still felt like it had plenty of flex and it sealed again when I put the sender back on. I did not use any other type of sealing stuff. However, the speed and urgency at which a project needs to be completed tends to be directly proportional to how likely the failure of a critical item will happen. As you said, it is 30 years old.

Is there anything about the sender wiper and wires that can be cleaned up to restore an accurate/stable fuel gauge reading? (Since I have one of those gauges that reads 'Full' for maybe an hour after a fill up and then drops to half or less with the usual needle bouncing.)

As you can see in the photo, the wires seemed clean and free of any build up. You could play around with the float position to raise it up. The trick is knowing how much to bend it. You need to have a full tank to know when it reads full and not get over bent. The bouncing needle is a different problem.

[Pat Conlon]

When bending the float rod to calibrate the fuel gauge needle position, a couple of things I've learned:

1) Calibrate the needle with 1/2 tank of fuel.

2) Bend the float rod in the middle. Bending the float up will lower the needle, bending the float down will raise the needle.

3) Small adjustments. It may take several tries (drain/refill) to get that needle where you want it.