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mvrk10256

FCR MX39 - Clogged starter nozzle thing - NOT JET - How to fix?

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Basically I have fixed everything else on the bike. Went to put in the carb, kicked it over, and nothing. Realized no smell of gas. 

 

Basically pumping the throttle, nothing comes out of that little jet that sits in the carb. I have tried brake cleaner, air pressure. Is there a way to clean that channel out?

 

Should I strip it down and try to soak the body for 24 hours and then blow it out again? &%$#@!ing things are like $400. 

 

 

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That is the AP nozzle. You need to confirm the check valve works, that the diaphragm is good and the linkage proper. If the AP passages are clogged, you'll need to clear. If you do not have the skill, let a pro do it, a FCR is easy to ruin.

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That is the AP nozzle. You need to confirm the check valve works, that the diaphragm is good and the linkage proper. If the AP passages are clogged, you'll need to clear. If you do not have the skill, let a pro do it, a FCR is easy to ruin.

 

I have the skill just lacking the knowledge. Now that I know what its called I found a few more threads that might give me an idea how to fix it. 

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I had the same problem on a yz450 that was sitting for a while, replaced all the jets and rebuilt the accelerator pump and still had no squirting out of that jet when you twisted the throttle, found the channel from the accelerator pump to the nozzle was clogged. Soaked it for a day in a gallon of carb cleaner for a day and it was still tough to work it all out but it did eventually clear out. Good luck

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My own damn fault. I used a bit of RTV to help the new bowl gasket stay and since I did not know how the AP worked, I accidently got some in there. Cleaned it out and now the carb works fine. Thanks guys. 

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Never use RTV anywhere around gasoline, for starters, never use sealer on any part of a carb, and generally don't use RTV on gaskets of any sort. 

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Never use RTV anywhere around gasoline, for starters, never use sealer on any part of a carb, and generally don't use RTV on gaskets of any sort. 

Absolutes are dumb. Using a drop fo RTV to help a gasket fit properly is no big deal, just dont put it on top of a fuel passage. 

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Absolutes like 'don't shoot yourself in the foot' are not dumb.  RTV is often a good substitute for a gasket (sometimes better than a gasket would be), but it makes an extremely poor gasket sealer.  There are vastly superior products readily available for use with gaskets.  That includes using it to anchor gaskets in place. 

 

RTV tends to release from 'rubber" engine gaskets and oil will leak between the gasket and the RTV. 

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