Author Topic: Best way to check needle&seat with vacum tester?  (Read 64 times)

Offline Mr.Pontiac

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Best way to check needle&seat with vacum tester?
« on: November 20, 2020, 07:21:11 AM »
I want to check all needle & seats for proper holding. I have a myte-vac, can`t find a hose to go over the seats. Is there a fitting you can screw them into to check?

Offline lightning boy

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Re: Best way to check needle&seat with vacum tester?
« Reply #1 on: November 20, 2020, 12:34:26 PM »
Install the needle and seat into the main body. then pull vacuum from the fuel inlet.

Offline Cliff Ruggles

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Re: Best way to check needle&seat with vacum tester?
« Reply #2 on: November 21, 2020, 04:46:40 AM »
That will work but you then supply 3 possible leak points, at the needle, gasket between the filter housing and carb, and the inverted flare where the fuel line seals.

I much prefer to check them with a large rubber  hose fit tightly over the outside of the inlet seat.

Even with that said we haven't seen any leakers for quite some time now.  About 15 years ago the suppliers sent out a batch of N/S assemblies where they missed the step in production that forms a seat and we had a LOT of issues.  Had to take every single one out of the package and test them before we could use or sell them.

These days its extremely rare to find a bad one, and when one runs into this issue a quick/light tap with a steel check ball into the seat will usually correct the issue........

Offline Mr.Pontiac

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Re: Best way to check needle&seat with vacum tester?
« Reply #3 on: November 21, 2020, 07:58:13 AM »
Cliff, exactly what I want to do.I can’t find a hose to fit over seat,should be easy, parts store suck here. Going to try again.The fitting on end of the vacum hose to Mytivac again may be troublesome.