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Need Some Help!!!

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I have an 03 DRZ 400S. I just installed a Clarke gas tank. The installation was pretty easy. However, now my bike will start w/ the choke out and idle for 10-15 seconds and then die. Then it will not re-start. It appears that the bike is not getting fuel??? Anyone have the same problems or ideas for a fix.

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The bike uses a vacuum operated petcock....no vacuum....no fuel.

You forgot to reconnect the vacuum line that runs from the right side of the carb to the small fitting on the fuel petcock. Find the hose and put it back were it was.

Common mistake.

Ray Stedronsky

Davis, CA

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Glad it worked out.

It's also important to know that motorcycles used to come with manual petcocks and you were supposed to know/remember to turn off the fuel when you stopped the engine.

Since the fuel gravity feeds to the carb, the petcock valve and the small float valve in the carb bowl is the only thing that's preventing all the fuel from running through the carb into the engine (where it leaks past the rings, contaminates the oil and causes big things to fail when the engine is run next time).

The vacuum petcocks were added inn the 80's because people (probably mainly in Californi.....go figure) were winning warranty claims for engine damage due to fuel contamination because.....see above.

This is all well and good but the vacuum petcock depends on a thin fragile diaphragm to work right. Over time, this diaphragm invariably wears out, leaks and allows the petcock to open even when you think it's closed.

What all this boils down to is that it is good practice to check the operation of the petcock at regular intervals. I do mine every oil change. Just make sure fuel is not running when then engine is off.

For paranoid believers in Murphy's Las (like me) the installation of a manual petcock either substitued for of added downstream of the standard petcock is normal practice.

Ray(more than you ever wanted to know about petcocks)Stedronsky

Davis, CA

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"This is all well and good but the vacuum petcock depends on a thin fragile diaphragm to work right. Over time, this diaphragm invariably wears out, leaks and allows the petcock to open even when you think it's closed"

Vacuum petcocks are spring loaded closed. The diaphragm opens the petcock when vacuum is applied. A bad diaphragm causes the petcock to stay closed when it should be open. So people run it on "prime" and that is where the "no shut-off" problem starts.

I do agree that all petcocks wear out and leak. Most (even new) are not reliable enough to keep gas out of the carb in long term storage. I always disconnect the fuel hose and plug the nipple for long term storage.

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