Fuel switch reserve not working

Howdy,
You can tell from my signature I'm a newb.
So then, I've been riding with the fuel switch in PRI because I thought that meant Primary...since looking around on the site I found out that the PRI setting is just for priming the engine after its been sitting for a while. I'm supposed to ride with the switch in ON.
With that said, I was riding to work today and the bike started to sputter which indicated to me that I needed to flip the switch to RES for the reserve tank. I accomplished this while riding, but nothing...I trickled to a stop, which was luckily only 100 yards from a gas station.
Any advice on why the RES didn't work? Could it be that while in PRI I used both the MAIN tank and the RESERVE?

Thanks in advance.
Mike

 

In PRI..yes you could use th whole tank
Maybe you switched to RES too late
Th fuel tap/petcock also needs vacuum from an intake manifold to work in th
ON and RES positions...it's th other pipe on th back of th tap.
It needs to be connected and functioning properly as does th diaphragm in
th petcock...there are many posts on here about it....'search' is y friend ... And Welcome

 

Thanks.

So based on other threads, it sounds like the OFF position is actually by turning the switch to ON and disconnecting the vacuum line.
Does that sound right?

 

No...ON means fuel flows if there is vacuum present in the vacuum line (i.e. the engine is running). RES means the same thing, except that the fuel is drawn from a lower point on the petcock. PRI means that the fuel will flow without any vacuum present (it can flow with the engine off).

This of course assumes that the petcock is in good working order and that all of the valves and seals are in good working order.

 

So how do you shut the fuel OFF, as would be required if you wanted to remove the tank, or for winter storage for example?

 

ON only lets fuel flow if the engine it running. So you would put it on ON (I know it's a little confusing). If fuel is flowing on ON, then you petcock valve is leaky and the rebuild kits may or may not fix it properly. You could always put a Briggs and Straton inline fuel shut off...to make sure the fuel won't flow.

 

Speaking of petcocks...
I recently bought a '82 XJ650 and the guy I got it from told me that he always left the petcock on 'reserve', not the 'on' position, he said this was because it was getting too much gas when it was 'on'. Is this normal or something that I should be concerned about?

 

off-topic here...but mosee as in mozee MSOE? Nice. I'm an '04 Grad in ME. You?

 

Haha, wow. Yeah, I go to MSOE, I'm actually an ME also, Freshmen though. Almost done with my first year! Small world, eh?

 

BS alert on that one - - that's simply not "accurate".

Another possibility is the in-tank screen/filter could be missing, giving you no "reserve" function.

 

Hey TIME, I'm wondering if my bike might have the in-tank divider missing. As stated earlier in the thread, I was on PRI accidentally and then when I ran out of fuel (sputtering) I switched to RES but I still rolled to a stop. Maybe my divider's missing, but can you see the divider with a flashlight and looking through the fuel filler opening on top?

 

Look at this thread:
http://www.xjbikes.com/Forums/viewtopic/t=24315/

Also linked in that thread is:
http://www.maxim-x.com/petcock.html

When on PRI, fuel is drawn from both the RES and ON inlet. I think the only way to verify if the divider is there is to take the petcock off. You can do this without draining all the fuel, but be careful how you turn it over because gas may leak out the cap.