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Removing purge/primer bulb altogether


NorthernCanuck's Avatar
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07-12-15, 05:05 AM   #1  
Removing purge/primer bulb altogether

The purge/primer bulb on my poulan chainsaw is damaged. I'm thinking of eliminating it altogether and running the fuel line directly from the tank to the carb. I'm thinking that all it will require will be a few extra pulls on the stater cord to prime the carb, and since it is such a small engine (30cc), the pull is light.

Has anyone done this and does it work?

 
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07-12-15, 06:20 AM   #2  
No, it won't work depending on the engine design. Without going into details the primer bulb forces fuel to the carb jets and not the engine directly. It also forces pressure and vacuum. Without the bulb your carb will be flooded on a permanent basis.

Google WHY IS THERE A PRIMER BULB ON SMALL ENGINES for a better explanation

 
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07-12-15, 06:26 AM   #3  
IMO it would be easier to replace the bulb than bypass it


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07-12-15, 07:06 AM   #4  
Primer bulbs are very inexpensive. I just bought a 5 pack from the big "A" online store for $7


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07-12-15, 12:27 PM   #5  
I want to thank all for their help. I just repaired bulb with a little bit of epoxy, let it dry, and put it back in. I didn't even use the bulb to prime/purge the air but rather just pulled on the cord a half dozen times or so to start it. I think the next time the bulb has a tear in it I'll just pull it out altogether and feed the carb directly from the tank and live with pulling the cord a few extra times to get the fuel to the carb and engine.

And one less link in the system is one less thing to go wrong in the future.

 
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07-12-15, 12:36 PM   #6  
Your fix will last through the first cycle. Gasoline will melt your adhesive and it will leak again. Gee, why not just fix it right and be done with it? Referring to post #2, your plan won't work, just like your repair. I buy them by the packs like Tolyn says. For the most part they all use the same size. One of my machines uses a larger size.

 
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07-12-15, 04:26 PM   #7  
Adhesives generally don't work with gasoline, but I used a two part epoxy and it has worked in the past on repairs. Even JB weld will work, if left long enough to fully cure.

Btw, I live in Canada, and everything is double the price of what Americans pay. And we can't always get these parts, for they are always on "special order", which means they can further gouge us. These bulbs come in all sizes too. And further more, I don't think purge bulbs are necessary on small engines that produce little compression and are easy to turn over. They are just a problem waiting to happen once again in the field.

But I appreciate your comments, for I will keep an eye on it tomorrow to see if it holds up.

 
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07-12-15, 10:01 PM   #8  
If the primer is separate from the carburetor, you can eliminate is just as you suspected. It will likely require a few more pulls, also as you suspected.


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