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Resealing jug nipples

Post Tue Sep 29, 2020 9:05 pm

Posts: 45
My basically brand new jugs from ACF American Cycle Fabrication are already leaking at the intake nipples. Montuckymatt on this board mentioned having the same issue with his and offered to speak to me on the phone about what he did to fix his. I can't get a hold of him now though!

Anyone have any experience with fixing this?

And yes in case you were wondering, it's pretty dissappointing to spend $2,000 on a top end from Paul Freibus at ACF and have the jugs begin leaking basically immediately.

I have been sorting out other issues with my UL and have really only rode the bike up and down my street a few times on short test runs. Basically 1 mile or less!!!!

Post Fri Oct 02, 2020 6:21 am

Posts: 105
Do they leak at the rivets or all the way around?

Post Fri Oct 02, 2020 1:58 pm

Posts: 45
I'm not sure yet. I sprayed them nipples with brake cleaner and it noticeably changed the idle, made it more consistent. It is also popping through the exhaust on the front cylinder and when spraying the nipple down it goes away.

I'm planning on borrowing a smoke machine to fog out the insides and try to pinpoint the exact leak source easier.

Post Sun Oct 04, 2020 1:37 pm

Posts: 3564
Location: Central Illinois, USA
Golly WildOne,...

Bubbles are a lot easier:

And at a constant, regulated 15psi,... It is absolute.


Post Fri Feb 19, 2021 1:59 pm

Posts: 45

I ended up making a rig that allowed me to pressurize the intake with air and test it with soapy bubbles from a rag.

Found the nipples to be leaking quite bad.

Changed the nipples out, and used Gasoila on the threads, per Montuckymatts reccomendation.

I also used set screws for the intake nipples instead of rivets. I believe they were a Colony part for panheads?

I think I have that problem solved.

Post Sun Oct 02, 2022 11:19 am

Posts: 3564
Location: Central Illinois, USA
So how'd it turn out, WildOne?

No news is good news?


Post Tue Oct 04, 2022 5:52 pm

Posts: 45

In between work, and any number of other projects/endeavors, I've been riding it often!!!

Just got back home from a ride:


Thanks for your help. I ended up getting some of that snooping fluid and trying it. I honestly prefer dish soap though, just me. I know you were a HUGE fan of my homemade test rig from another thread, so here's some of the same pictures incase anyone stumbles upon this thread instead!!

I can pressurize the intake tract and spray soapy water on everything and carefully examine it all.



Post Fri Oct 07, 2022 8:49 am

Posts: 3564
Location: Central Illinois, USA
Whatever works, WIldOne!

Did anybody ever alert ACF to the issue?


Post Tue Oct 11, 2022 3:16 pm

Posts: 45
ACF is long gone by my understanding. It's a shame as Paul really seemed to be passionate about these flattys. Nonetheless, having shitty business practices was enough to do them in I suppose.

Post Wed Oct 12, 2022 10:03 am

Posts: 3564
Location: Central Illinois, USA
...Nonetheless, having shitty business practices was enough to do them in I suppose.

I can testify to that, WildOne!

My practices were horrible.

I was never a "businessman".

(But somehow, after four decades, its the government taking me out of business.)


Post Wed Oct 12, 2022 1:37 pm

Posts: 45
I think it was a little more than that in this case. Not communicating with people for months (or more) or worse, telling them their parts are about to ship several times in a row until they finally start outright ignoring you.

Just a little basic honest communication would have gone a long way.

My understanding is that Paul was knocked down by some personal losses. I get that 100%.

I was pretty angry for a while about my experience, but I'm over it now. Shit happens.

It's just sad. Sad for everybody.

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