Cast iron fuel filter periodically leaks from the bottom screw

[Tim Ayers]

My cast iron fuel filter periodically leaks from the bottom screw.

It's not a constant leak, but it's wet. It doesn't do it all the time. Most times it will do it if the car isn't driven in a few weeks. It will leak/drip some and then stop after driving a bit.

I used a new lead washer and the ensured the mating surface was flat. What are some other causes of leaks with this units? I'd like to get it to no leaks.

Thanks.

[Gary WA]

tighten a little more

[BRENT in 10-uh-C]

Be careful on tightening because the threads are generally easy to strip.

For clarity, are you thinking it is leaking at the lower nut, -or is it leaking from the drain petcock? If it is from the lower nut, use Loctite 569 to seal it. If it is the drain petcock, use a small wood dowel and valve grinding compound to burnish the seat inside the nut. Then polish the tip of the petcock with emery paper to cleanup the end. That should take care of the leak if it is from either of those areas.

[Gene F]

What if you true it flat just ever so slightly with a file?

[Tim Ayers]

Originally Posted by BRENT in 10-uh-C

Be careful on tightening because the threads are generally easy to strip.

For clarity, are you thinking it is leaking at the lower nut, -or is it leaking from the drain petcock? If it is from the lower nut, use Loctite 569 to seal it. If it is the drain petcock, use a small wood dowel and valve grinding compound to burnish the seat inside the nut. Then polish the tip of the petcock with emery paper to cleanup the end. That should take care of the leak if it is from either of those areas.

Thank you, Brent. I think it's coming from both, but could be mainly from the drain petcock because the flat spot in between the four cross bars will be wet.

I'll take it off and report back what I find. Odd that it only does it every once in a while.

[Tim Ayers]

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Originally Posted by Gene F

What if you true it flat just ever so slightly with a file?

Thanks, Gene. I did do that, but will do it again to make sure.

[rotorwrench]

The valve on the bottom allowed for sump drainage of water. It may have had a lot of use over the years. If grit got in the valve then it can scratch the seating surfaces.

[Tim Ayers]

Originally Posted by rotorwrench

The valve on the bottom allowed for sump drainage of water. It may have had a lot of use over the years. If grit got in the valve then it can scratch the seating surfaces.

It looked good when I refurbed it, but I'll check it again once I take it off.

[ronn]

if it persists, just swap it out.......

[Tim Ayers]

Originally Posted by ronn

if it persists, just swap it out.......

Yes, I picked up a nice one at Hershey this year and that's the plan if it keeps leaking.

[Kurt in NJ]

tin the tip with solder, tighten it, you need to take the whole bottom of to clean the screen anyway, keep a few spare lead seals, they seem to be ok for 3 uses or so

[nkaminar]

Try some EZ Turn. https://www.aircraftspruce.com/catal...ezturnlube.php