Why wont my carb prime ?

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Keith81

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What makes a carb bubble not prime?


Its tight, I did check the screws, It sounds like an air leak but I don't know what to check to replace ?


Help needed as usual over here, LOL


and as always it's much appericated!


-Keith
 
Which way do the fuel lines go? My primer bubble appears to be fine with no damage to it...
 
The return line (The line without the filter at the end) goes to the top fitting. The line with the filter goes to the bottom fitting. The filter is in the tank, obviously, so you might have to pop the tank grommet out to see which line has the filter on it. Or you could just blow into each line and feel for resistance. The line with the least amount of resistance is your return.
 
Deluge said:
The return line (The line without the filter at the end) goes to the top fitting. The line with the filter goes to the bottom fitting. The filter is in the tank, obviously, so you might have to pop the tank grommet out to see which line has the filter on it. Or you could just blow into each line and feel for resistance. The line with the least amount of resistance is your return.
Ill check these in the am, Thank you for the response...


If they are on correct, what would be my next step ?
 
I'd double check that bulb again. I had a crack in mine that was almost invisible. It only opened up when the bulb was depressed. It caused the same symptoms as what you are having.
 
I know DDM has ultra fast shipping, at least for me in New York anyways they do, but I was wondering, is this a part I could get at a local small engine shop. I kinda wanna get it fixed today so me and my buddy can bash for a couple hours...

If not I'll be ordering from DDM today.

Do you recommend I get the part for under the primer bubble as well, looks like a diaghpram or something of that nature...

Its like I push the primer bubble, I can take the fuel line off and it'll shoot fuel like a mo fo, but only a little bit is gettin into the primer bubble, the truck wants to start but its not getting enough fuel, I put a new ngk plug in it and after hittin the primer bubble about 20 times the truck started and ran fine for about a minute til I hit the throttle, I don't think the engine was warmed up enough yet..

These trucks drive me crazy between the XT and my MT but I sure do love bashing them and they are a hell of a lot easier to work on then my t-maxx's and savage x.
 
Whoa!

Deluge said:
The return line (The line without the filter at the end) goes to the top fitting. The line with the filter goes to the bottom fitting. The filter is in the tank, obviously, so you might have to pop the tank grommet out to see which line has the filter on it. Or you could just blow into each line and feel for resistance. The line with the least amount of resistance is your return.
Did I read this right Deluge? The line with the filter goes to the bottom? Are you sure? Coz' all this time I had the line with filter connected to the top fitting. And I've been running it this way for a while and it was running great although I did notice the bubble seem to be empty after running a while and when it stalls I look at it and the bubble is empty.Whoa! :eek: Then how come my MT still managed to run all this time eventhough I had the gas filter line connected to the top? Sure pays to check the forum whenever possible. You always learn something new! :D
 
Keith81 said:
I know DDM has ultra fast shipping, at least for me in New York anyways they do, but I was wondering, is this a part I could get at a local small engine shop. I kinda wanna get it fixed today so me and my buddy can bash for a couple hours...If not I'll be ordering from DDM today.

Do you recommend I get the part for under the primer bubble as well, looks like a diaghpram or something of that nature...

Its like I push the primer bubble, I can take the fuel line off and it'll shoot fuel like a mo fo, but only a little bit is gettin into the primer bubble, the truck wants to start but its not getting enough fuel, I put a new ngk plug in it and after hittin the primer bubble about 20 times the truck started and ran fine for about a minute til I hit the throttle, I don't think the engine was warmed up enough yet..

These trucks drive me crazy between the XT and my MT but I sure do love bashing them and they are a hell of a lot easier to work on then my t-maxx's and savage x.
You could try. I'd take the carb so they can look at it and get you the right part. Maybe they'll help you diagnose the issue. Couldn't hurt to try.
 
powerslave69 said:
Did I read this right Deluge? The line with the filter goes to the bottom? Are you sure? Coz' all this time I had the line with filter connected to the top fitting. And I've been running it this way for a while and it was running great although I did notice the bubble seem to be empty after running a while and when it stalls I look at it and the bubble is empty.Whoa! :eek: Then how come my MT still managed to run all this time eventhough I had the gas filter line connected to the top? Sure pays to check the forum whenever possible. You always learn something new! :D
The return line could go into the tank deep enough to feed the carb until the fuel level drops just below the lines length, thus causing the engine to stall.
 
got it!

Deluge said:
The return line could go into the tank deep enough to feed the carb until the fuel level drops just below the lines length, thus causing the engine to stall.
Damn, I never knew that! :eek: Ok, so line with filter connects to the bottom fitting...got it! Thanks again:D
 
Deluge,

I appericate ya always responding to my questions brother!

Your the man!~
 
Ok so I went out and got a new primer bubble, while inspecting the white piece underneath the bubble where the fuel line connects Toni noticed a small tear on the copper looking gasket thing in the middle, also where you connect the fuel line that piece twists to whatever angle you want, it doesn't do this on my MT. Also the black gasket underneath the white piece looks like it's seen better days, what part numbers am I looking at to replace the black gasket and the white piece which the fuel line connects to? I also noticed when I press the primer it pushes air bubbles out of the fuel filter in the gas tank, is that normal? I could actually get a little fuel in the bubble before I took it apart and replaced the bubble. I'm stumped, deluge I need your help brother!
 
yknotrc said:
Sounds to me like you have a bad fuel pump diaphragm.Here is a good link !

http://wem.walbro.com/distributors/servicemanuals/WTseries.pdf
Yikes,

I rather buy a new carb then go fidddling that deep into the carb, LOL !!!

Thanks for the links, I actually found a local shop around my way that sells parts for small engines, I will call tomorrow to see if they have this in stock, the new carb that is... I think just gettin a new carb will solve all these bs problems I'm having, and for the price is worth not having a headache... Now I just gotta replace the base gasket on my MT and I'll be bashing both the XT and the MT !!!

:)
 
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I'd recommend the 668. 813's have throttle shaft issues. I'd also buy a rebuild kit for the old carb, learn how to rebuild it and use it as a backup. What model is it? If your local shop doesn't have the 668, here's a link.

Walbro WT-668 Carburetor w/Free Choke Lever

If the carb you have is a 668, here's the rebuild kit, if you want to use it as a backup.

Walbro WT-499 / WT-603 / WT-668 Carb Rebuild Kit K20-WAT

Here's a link to the white plastic top.

Walbro WT/WA Carb Plastic Top

As far as the bubbles in the tank when you press the bulb, are the lines hooked up right?
 
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