Help with XR350

[user 122190]

This 1983 bike started leaking gas last fall. To late in the year for me to bother with. Yesterday I started in on the project. What a PITA to get the Carburetor out!!!! I put the tank on the bench and supported the carb beneath and hooked up the fuel line. It is a slow leak and over an hours time can create quite a puddle. The problem is I can't see where the gas is coming from. My newest idea is to sprinkle baking flour over the carb, and then sit and wait a few or more minutes, and then hopefully I can spot the source of the leak.

Any other ideas? Maybe food coloring to help darken up the gas to help spot the source?

 

[bigbadbob]

Float bowl gasket is bad/loose, you may try and snug the four screws.
Or your needle and seat are bad or stuck or have a small bit in there.
You may try tapping, not beating on the carb. Rocking bike side to side.
Not sure if you can get the carb off easy,, some want engine pulled.
Some you can sneak off if the manifold is supple, airbox can e a ***** to
Good luck
Some sites
Thumper talk
Adv rider

 

[user 122190]

I sprinkled flour around the twin carburetors and did the leak test. It does look like it is coming from between the carb and its float bowl. The gasket or rubber ring was old and crusty, but intact. I cleaned it up, and put some sealant all around, and will let it sit a day. Tomorrow I will hook it up to the gas tank and see if it leaks after an hour or two.

It is a nice little bike, but as it is nearly 40 years old, everything is likely to fail and at anytime. I can't afford or justify a new one, and this bike is for putting around in the mountains, exploring old logging roads, in bad shape or over grown with new small pines. I'll just keep it going with minimal expense, for as long as it is willing.

 

[grizz55chev]

I sprinkled flour around the twin carburetors and did the leak test. It does look like it is coming from between the carb and its float bowl. The gasket or rubber ring was old and crusty, but intact. I cleaned it up, and put some sealant all around, and will let it sit a day. Tomorrow I will hook it up to the gas tank and see if it leaks after an hour or two.

It is a nice little bike, but as it is nearly 40 years old, everything is likely to fail and at anytime. I can't afford or justify a new one, and this bike is for putting around in the mountains, exploring old logging roads, in bad shape or over grown with new small pines. I'll just keep it going with minimal expense, for as long as it is willing.

The needle and seat are leaking, gas should not reach the height of the top of the bowl. A good trick to clean the seat is chuck a q- tip in a drill and polish the seat, YouTube is full of guys that have success with this trick.

 

[user 122190]

The needle and seat are leaking, gas should not reach the height of the top of the bowl. A good trick to clean the seat is chuck a q- tip in a drill and polish the seat, YouTube is full of guys that have success with this trick.

It would flow out the Overflow tube if that were the case. I did check and that is not clogged. There is something else going on, and I will figure it out. The bike was always a little hard to start when warm. I would have to hold the throttle open 1/4 to 1/3 to restart when warm.

 

[grizz55chev]

Good luck!

It would flow out the Overflow tube if that were the case. I did check and that is not clogged. There is something else going on, and I will figure it out. The bike was always a little hard to start when warm. I would have to hold the throttle open 1/4 to 1/3 to restart when warm.

 

[user 122190]

The gas leak is fixed. Sealant did the trick. Such an old bike. I did find a few other things damaged or broken, but put it back together anyways. Started right up and will be good for another couple of years. After that I will likely drop it off at a salvage business and be done with the beast.

Got me thinking, it sure was good to buy the ATV new. I also looked into buying a new and similar bike, but dayum they is expensive. The ATV seems such a deal in comparison. Not as much fun, but so much more practical for getting work done.