Primer bulb won't prime, compressed air to port on carburetor squirts gas

philnotfil

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  • / Primer bulb won't prime, compressed air to port on carburetor squirts gas
Briggs and Stratton 122T02-0377-B2

Replaced gasket between air filter and carburetor and primer bulb. When I apply compressed air directly to the port on the carburetor it squirts gas through the nozzle in the carburetor, so the problem is upstream from there. The old gasket had a well defined channel for the path of the air from the primer bulb. New gasket does not. Do I need a different gasket? Do I just tighten the bolts more until it has a good seal?

Any suggestions here?

Thanks,
Phillip
 

Rivets

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  • / Primer bulb won't prime, compressed air to port on carburetor squirts gas
Make sure the three screws holding the air filter base to the carb are very tight, just don’t strip them. If that doesn’t work the base is warped and need to be replaced.
 

Narko

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  • / Primer bulb won't prime, compressed air to port on carburetor squirts gas
I had that problem recently ,perhaps u can see what in did in a post below. Yes, I did not order the replacement gasket online because the displayed gasket did not seem to have the long curved path for the slightly compressed air from the primer bulb to travel. Instead I made my own gasket from foam tape (like 3M makes). I think never mind this warped interface thing. If the gasket is thick enough and is compressible it should compensate for any interface issues between the primer assembly and the carb.
 

Narko

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  • / Primer bulb won't prime, compressed air to port on carburetor squirts gas
The mounting tape is sticky on both sides which has advantages and disadvantages.
 

philnotfil

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  • / Primer bulb won't prime, compressed air to port on carburetor squirts gas
Inspired by Narko, I sealed the channel with some electrical tape, trimmed off what was in the way, put it all back together and worked perfectly. Teenage son is out mowing the lawn now :)
 

waylonJ

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  • / Primer bulb won't prime, compressed air to port on carburetor squirts gas
Inspired by Narko, I sealed the channel with some electrical tape, trimmed off what was in the way, put it all back together and worked perfectly. Teenage son is out mowing the lawn now :)
I like this approach! I have about 10 broken mowers I am going through and dread when I see one with the side-primer and a briggs engine. I even tested the primer circuit on a good engine and it worked fine but it would not start so I cleaned the carb and reassembled the carb, backing plate, etc and the darn primer circuit did not work. I was super careful to evenly tighten the 3 bolts.


Also, many claim to use two gaskets to help fill any gaps. On three different engines with a primer issue, this NEVER worked. I even tried 3 gaskets - no luck. I did place the gasket on the air-filter backing plate and used some mild glue to seal the edges of the gasket and it looks like it will work - but I love the idea of using electrical tape!


Any other tricks on this issue? I also thought about applying some "super-tacky" gasket material to the edges of the gasket to help create the seal. This really is one of the worst design ideas I have seen out of Briggs.
 

kwgerloff

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  • / Primer bulb won't prime, compressed air to port on carburetor squirts gas
Use two gaskets. Sometime you just have to replace the base. They can warp if you over tighten the bolts .
 

StarTech

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  • / Primer bulb won't prime, compressed air to port on carburetor squirts gas
You got to use wedge gasket setup. Take a close look at the impression left one gasket and make a wedge gasket to add pressure where there is none.
 

waylonJ

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  • / Primer bulb won't prime, compressed air to port on carburetor squirts gas
I did confirm I was able to fix two different engines with a primer issue by using a sealant /glue to seal the edges of the gasket onto the base plate. Happy to have this sorted out.
 
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