I noticed when I got my AFPR from MAllory, it said not to use teflon tape to eal the threads. Can anyone tell me why? Im getting leaks from 2 of the ports, and I cant stop them. I originally used thread sealer, the same thing I used on my freeze plugs and head bolts, but I cant get it to seal properly. Can I use teflone on the regulator, or should I completly stay away from it?

Im thinkin they're just thinkin some people would overdue it, and the teflon would get into the regulator. I dont think a little would hurt, just enough to seal it. I gotta get these lines sealed asap!

Not sure about the teflon tape part, probably they figure it could either blow out or come off and clog something, not sure. I used the thread sealer by Permatex and it works fine for me.

this is why i said earlier....mallory 4309 is not that great...

well, other than this, I havent had any problems out of it. I mean, its a universal part, so they cant expect everyone to use AN lines. They gotta think of people, like me, who are on a budget for the time being and can jsut use barbed NPT fittings and rubber hoses.

Screw it, I put a little teflon on it. Worse case scenario itll f**k up the regulator (which is rebuildable), or screw up the carb (which Im replacing with a 650 DP soon). Either way, I dont see how teflon is going to interfere with the fuel delivery or regulator as long as it isnt protruding into the lines/flares, whatever the case may be.

Shreds of teflon tape can come loose and find their way into inconvenient places. Liquid teflon or some other fuel safe thread sealer is a better idea.

I used it, no leaks. No problems.

ditto but AN is the only thing that fits "properly"....

AN or some other flared or gasketed fitting. Pipe threads are more commonly used though.

I used teflon tape made for sealing gas lines. I got it at Lowes. It is yellow and slightly more expensive. I couldn't get anything else to seal. Don't put it on the first few threads and you shouldn't have any problems with it clogging anything.

The tape has the tendency of coming off when being tightened, even when it's being wrapped in the right direction on the thread. It 'will' work, but liquid sealant is better...

What's you're fuel pressure? What's the size of you're return line? I ran the Mallory 4309 on my 454 w/TPI pump, and it never leaked, well, in the beginning it did... during the ole trial and error process.

I think Mallory replaced the 4309, with the 4307-M... it's supposed to be much better. Lemme see if I can find a link for ya.

Here ya go;

Click Here

not for the returnl line...its AN.

Not for the return line on what?

With the engine off and pump on, I can get a consistent 5.5psi. Anything over that the gauge starts jumping. With the engine on, I can get it a little over 6psi. Im using the stock return and feed hard lines with 3/8 rubber hoses connected to the regulator. I know i know, trashy lookin, but its workin for me now, and it IS only temporary.

So far the teflon tape seems to be working. I can it last night for a little bit trying to get the timing right, and it didnt leak once. But only time will tell. By then hopefully Ill have all new AN lines.