Fuel pump regualtor fitting sizes - HELP! | AEM
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Last seen: 5 months 1 week ago
Joined: 04/15/2020 - 05:09
Fuel pump regualtor fitting sizes - HELP!

HI There. i have a 302BK regulator. The main input fitting's are listed as AN6 and i have managed to fit these fittings ok. The output port (at the bottom of the regulator) is listed as an AN6 - 8.  I cannot find anyone that has heard of an AN6 -8  fitting as standard AN6 fittings are dash 18. i tried fitting a standard An6-18 with an o -ring and another with a crush washer but they both just leaked.

So can someone clarify what this fitting size is and a link to where i can buy a plug to cap this port off please ?


thank you.

Jason  (UK)


Last seen: 10 min 57 sec ago
Joined: 06/06/2014 - 09:31
Not sure where you're seeing

Not sure where you're seeing that the port is AN6 - 8.  Here's what's in the instructions:

Yes there is a typo but as you can see, the port thread sizes are the same.  They're -6 AN on the side and -6 AN on the bottom.  The thread for -6 AN is 9/16"-18.  

You can not plug the bottom port otherwise the regulator will not work.  This regulator, and all regulators of this type, are return type and that bottom port is the return port.  Plugging or blocking it would mean that regulator can't actually regulate pressure.  

If you have a leak, then perhaps there's something wrong with your regulator but I've always used fittings with crush washer and they seal up fine.  Where did you buy your regulator?