Author |
Message |
Pbesanson
| Posted on Sunday, May 03, 2009 - 10:26 pm: |
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Just acquired a 2003 Blast with 400 actual miles. Hoped it was just a clogged pilot jet but the carb was amazingly clean throughout. Starts extremely well and runs strong after it stumbles through the flat spot. Intake boot appears sound but I did not remove it from the head for inspection. Are the boot failures easily seen or can they be very small? What else should be checked? |
Dummkauf
| Posted on Monday, May 04, 2009 - 12:07 am: |
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Not sure what else to check, but as far as the boot is concerned you could try the WD-40 trick one of my friends once showed me. Just start the bike and while it is running spray the boot down with WD-40. If your idle changes when you do this then you either have a small crack or the boot is not sealing up tightly enough on the carb or head and needs to be replaced. Oh, and the engine will smoke a little after you are done with this as the WD-40 burns off. (Message edited by dummkauf on May 04, 2009) |
Ezblast
| Posted on Monday, May 04, 2009 - 01:06 am: |
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Are the jets tight? is the air-screw the right amount out - even sealed this could have worked looser - has happened - could just be loose boot? kick stand switch is also famous - twist wires together, and clutch switch - disable by flipping center diode. Sitting a long time - maybe the rubber of the slide went. EZ |
Pbesanson
| Posted on Monday, May 04, 2009 - 02:43 pm: |
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By air-screw I assume you mean idle-mixture screw? I'm used to seeing an O-ring seal on these screws but there wasn't one. If it's turned out more than 1-turn, the idle speed goes way high. I'll try sealing the screw boss on the carb with a finger. Will also recheck the slider diaphragm. I know that even a small pin-hole can cause weird problems. Forgot about the WD40 trick..., will try that also. |
Gearheaderiko
| Posted on Monday, May 04, 2009 - 09:04 pm: |
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"I'm used to seeing an O-ring seal on these screws but there wasn't one." Sounds like you've found your problem! There is supposed to be an o-ring on the screw along with a washer. However since you're not supposed to drill the plug out that covers the screw, there arent any pictures to show you this! |
Damnut
| Posted on Monday, May 04, 2009 - 10:13 pm: |
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You can use brake cleaner to check for air leaks as well. The idle will rise if there is a leak. Also brake cleaner won't leave an oily residue. Figured I'd share. |
Ezblast
| Posted on Monday, May 04, 2009 - 11:45 pm: |
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In fact it is what I use besides WD40 on my bike's metals - alternating - EZ |
Pbesanson
| Posted on Tuesday, May 05, 2009 - 03:09 pm: |
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I simulated an O-ring seal on the idle screw by holding a finger over the screw boss but that didn't help either. The WD40 test revealed no vacuum leaks anywhere.I'm going to go through the carb one more time to make sure nothing is clogged and the slider diaphragm is sound. |
Ezblast
| Posted on Wednesday, May 06, 2009 - 12:32 am: |
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You tested that the roll over valve and the line is ok? Your grounds are tight? Your safeties nullified - the clutch safety switch? (flipping the center diode) Kick stand safety switch? (cut & twist the two wires coming out of the switch together) I forgot - how does one override the BAS (BankAngleSensor)Safety switch? You'll want to rule out all that as well, loose plug wire do it also. EZ |
Ezblast
| Posted on Wednesday, May 06, 2009 - 12:34 am: |
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Replace boot as well - cheap - 10 dollar part. Rubber gets old. EZ |