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The ole "Failed Petcock, Gas in the oil" question.

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Thanks so much for the help so far.  I have a 2009 DRZ 400S that I purchased from a dealer as a trade in.  It already had TONS of mods to include the 3X3 and a carb jet kit from JD Jetting.

After I bought it, I rode it on and off road for about 1000 miles. (In that time, I did run it out of gas twice ****Full disclosure****) It did sit for about 9 month without being ran.  I was in Japan and have move it across country now.  So the original symptoms were:

1, A super hard start when cold.  You would have to give it about half throttle to keep it running.  Once it died....It would not restart.

2, Idle seemed a bit rough and maybe too lean. (Also surges...If the throttle is held in position the engine will speed up and slow down in a cycle. Seems to be about even time to speed up and even time slowed down.)

My first thought was carb related/gunk in the carb. (Because I ran it out of gas twice) I took the carb apart and there was some gunk on the main jet needle (Item 9, page 157, Clymer's Manual)  While I was at it, I also replaced the spark plug.

After that....No change.  I read about the fuel draining into the oil sump (here on Thumper Talk) and checked my oil dipstick.....It seemed to be ALL fuel.

*****************************************************************

I performed an oil change including the filter.  When I drained it, it appeared to be mostly fuel and the filter element was soaked in fuel as well.

Once complete, It started right up and seemed to be OK.  Still idles a bit off, but I can adjust that (prolly have two separate issues here)

However, when I check the oil it still smells HEAVILY like gas still...

AND, I also had trouble starting it up a second time.  By now the battery may have been a bit drained. (Its on a Battery Tender now)

From the riders that have had this problem, did you run it for awhile and do another oil change?

Just looking for recommendations here.  Maybe a drain and flush, where I leave the plug out and dump a few quarts of cheap oil through it?  Could the stator be an issue? (with the surging)

Thanks for the help.

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I believe the problems are fuel related not stator.  It may take more then 1 oil change to purge the gas out of the motor.  No motor drains all the oil during an oil change. But have you done anything to correct the fuel contaminating the oil?  If not corrected, contamination can occur over night.

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Noble, Thanks for the reply..... Honestly, I think the fuel issue was just some dummy (me) leaving the petcock in PRI.    Now that I know that is wrong, I have it in "ON"

When I had the tank off.... I had the petcock in "ON" and it did not leak a drop in the two hours it was on my bench.  I did buy a new needle O ring that I plan to replace. (It had some gunk on it)  I think it was just an "Incorrect petcock position" error, vice an issue with the petcock.

How long would you recommend running it?  Or should I go get some cheap 10w 40 from Walmart and just slowly run it through the system as it sits.  Then replace the filter and oil again before trying to run it long term?

Also, what do you think about trying to set the Idle?  Should I wait until my oil/fuel issue is fixed?  Or try to adjust it while running it in the interim?

 

Thanks for your help.

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I'd probably run the motor to full warm, 10 /15 min before draining the oil again.  Set the idle after the oil/fuel issue is resolved.

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Could be leaking thru the carb needle valve seat o ring.  I fixed that and changed to manual petcock prob solved. I thought months later my oil smelled again like fuel again then someone on here suggested to hold a flame to dipstick in a safe place see if it will ignite.  It did not. Maybe not best idea but it worked for me to verify.  I think w the vacuum petcock it can leak thru the vacuum line but not sure.  Get a raptor for cheap or a pingel if u want something nicer, check valve seat o ring or just put flame.to.dipstick and to know for sure. 

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If the gas isn't leaking more in the oil you can just go for a long ride , 30-40 minutes at full temp to burn off any fuel still left in the motor and all will be fine . If you want you can change oil again,doesn't hurt anything , but I don't feel there is enough left in the motor to require it , I didn't back when mine did it . The oil vapor box will be saturated also so for a little while it will run rich when warm till all that is vaporized and burnt .

You need to make darn sure no more fuel is seeping anymore with that o-ring . If the needle seat and o-ring is good , it shouldn't matter if the petcock is leaking or not , fuel will be stopped . Just much better to have it working .  A caution to the Raptor petcock recommendation , don't do it if you have the stock steel tank , they will not fit and the fuel line will be crammed tight against the carb , wrong outlet angle for that tank .

 

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Thanks for the replies.  I did buy that needle O ring while I was at the dealer getting all the other goods for the oil change.  I just was not sure if some of that residual fuel would damage the new oil filter membrane.  I will try to take it for a ride today and burn the rest of the fuel off.  

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14 hours ago, TheWoodser said:

Thanks for the replies.  I did buy that needle O ring while I was at the dealer getting all the other goods for the oil change.  I just was not sure if some of that residual fuel would damage the new oil filter membrane.  I will try to take it for a ride today and burn the rest of the fuel off.  

If after the ride u still have problem When u install the needle valve seat oring check the needle valve itself with mag glass, look closely for any steps or dents, if the needle valve has any visible wear on the viton tip (or a ring forming around it) that can cause fuel to leak thru too.  

Edited by Sasha Rudolfski
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On 10/21/2018 at 5:49 AM, jjktmrider said:

If the gas isn't leaking more in the oil you can just go for a long ride , 30-40 minutes at full temp to burn off any fuel still left in the motor and all will be fine . If you want you can change oil again,doesn't hurt anything , but I don't feel there is enough left in the motor to require it , I didn't back when mine did it . The oil vapor box will be saturated also so for a little while it will run rich when warm till all that is vaporized and burnt .

You need to make darn sure no more fuel is seeping anymore with that o-ring . If the needle seat and o-ring is good , it shouldn't matter if the petcock is leaking or not , fuel will be stopped . Just much better to have it working .  A caution to the Raptor petcock recommendation , don't do it if you have the stock steel tank , they will not fit and the fuel line will be crammed tight against the carb , wrong outlet angle for that tank .

 

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I just installed one and it is fine. I removed the spacer and ran automotive fuel line rather than powersports and looped it around the air intake. It works great. 

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