Shovelhead A place to talk about Shovelheads.

Sealing pin hole leak in tank.

Thread Tools
 
Search this Thread
 
Old Jul 29, 2020 | 08:58 AM
  #1  
mbco's Avatar
mbco
Thread Starter
|
Advanced
Joined: Oct 2017
Posts: 87
Likes: 9
From: Colorado
Default Sealing pin hole leak in tank.

While "de-rusting" the tanks on my 78 FXE using Metal Rescue (which seemed to work great by the way) I found a small pinhole leak in the RH side tank down by the front mounting bracket. Anybody had any positive or negative experiences with J-B Weld TankWeld or similar products? I am uncovering some products may not stand up to ethanol fuels.
 
Reply
Old Jul 29, 2020 | 09:09 AM
  #2  
Uncle Larry's Avatar
Uncle Larry
Seasoned HDF Member
Veteran: Army
15 Year Member
Joined: Jan 2011
Posts: 157,417
Likes: 56,983
From: Michigan 15 Minutes East Of Hell
Default

I'd imagine that you will be refinishing the tank ... I'd see if you can get someone to braze it ... or stop at by a radiator shop and see what they say ... Most "Magic in a Can" products aren't what they're cracked up to be .. Of course condition of the tank will determine if it can be brazed ... Good Luck
 
Reply
Old Jul 29, 2020 | 10:23 AM
  #3  
Architect's Avatar
Architect
Seasoned HDF Member
15 Year Member
Joined: Apr 2010
Posts: 9,524
Likes: 7,861
From: Long Island, New York
Default

Listen to Uncle Larry, radiator shop can pressure test and seal it up. If you have one hole, you may have more, good luck.
 
Reply
Old Jul 29, 2020 | 12:14 PM
  #4  
DooWop's Avatar
DooWop
Cruiser
5 Year Member
Liked
Joined: May 2020
Posts: 117
Likes: 44
From: Corrales NM
Default

I have filled a tank with water and brazed a pin hole shut. Problem is if there is one there might be others down the line. The radiator shop sounds like a good idea. Will tank creme do any good?
If a tank s filled with water, flushing with denatured alcohol will displace any water remaining. Or the product Heat. Don't use bourbon.
Someone at Bonneville said "Gasoline's for cleaning parts, alcohol's for drinking, and nitro's for racing." They're nuts out there.

I just came across a gas tank sealer in JP Cycles restore catalog. $40-59. Might be worth a shot.
 

Last edited by DooWop; Jul 29, 2020 at 12:39 PM.
Reply
Old Jul 29, 2020 | 03:11 PM
  #5  
mbco's Avatar
mbco
Thread Starter
|
Advanced
Joined: Oct 2017
Posts: 87
Likes: 9
From: Colorado
Default

I guess I forget to mention tanks are in good condition, painted and hole is down low near front bracket. with no other leaks detected when filled with liquid - no pressurized. I was HOPING not to have to braze (and find somebody qualified) and repaint tank and trying epoxy based product method as first (and hopefully only) step. I'm heading out to shop to start sanding paint to see what it looks like bare. I'll post a pic.
 
Reply
Old Jul 29, 2020 | 05:20 PM
  #6  
john lee's Avatar
john lee
Stellar HDF Member
5 Year Member
Photogenic
Photoriffic
Shutterbug
Joined: May 2018
Posts: 2,165
Likes: 435
From: australia
Default

depending exactly where the pin hole is a good brazer could save the outside tank paint and touch up the braze area
 
Reply
Old Jul 29, 2020 | 06:04 PM
  #7  
johnjzjz's Avatar
johnjzjz
Seasoned HDF Member
15 Year Member
Top Answer: 3
Joined: Nov 2006
Posts: 12,878
Likes: 5,449
From: la la land jerzey
Default

normally what you have is a stress crack in the fixture between the tank and the mounting bracket - as these old buckets do shake quite a bit - radiator shop is the only option

in the shop we would then seal it with the red coat -((( only ))) did i say only hope so
 
Reply
Old Jul 30, 2020 | 12:10 PM
  #8  
mbco's Avatar
mbco
Thread Starter
|
Advanced
Joined: Oct 2017
Posts: 87
Likes: 9
From: Colorado
Default

Thanks for the advice brothers. I know pic is huge but wanted to show detail. For orientation breach is it located on lowest inside corner just outboard of mounting flange of rightside tank. I got down to metal with Dremel and stopped when I realized it may be the seam of two pieces. When i probed inside that gap I can pick out some non-metal material which I can't identify.
 
Reply
HD Forum Stories

The Best of Harley-Davidson for Lifelong Riders

story-0

7 Surprising Harley-Davidson Products that Are Not Motorcycles

 Verdad Gallardo
story-1

8 Best Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-2

10 Worst Harley-Davidson Motorcycles Ever

 Pouria Savadkouei
story-3

Killer Custom's Jail Break Is The Breakout That Refused to Blend In

 Verdad Gallardo
story-4

Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?

 Verdad Gallardo
story-5

Harley-Davidson Reveals Super Cool Cafe Racer Concept

 Verdad Gallardo
story-6

Engraved Rebellion: Inside Bundnerbike's Glam Rock II

 Verdad Gallardo
story-7

10 Motorcycles You Should Never Buy

 Joe Kucinski
story-8

10 Things Harley-Davidson Needs to Fix in 2026

 Verdad Gallardo
story-9

Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider

 Verdad Gallardo
Old Jul 30, 2020 | 01:36 PM
  #9  
hvacgaspiping's Avatar
hvacgaspiping
Seasoned HDF Member
Veteran: Navy
10 Year Member
Liked
Community Favorite
Joined: Apr 2013
Posts: 32,851
Likes: 17,886
From: Newcastle, OK
Default

Originally Posted by mbco
I guess I forget to mention tanks are in good condition, painted and hole is down low near front bracket. with no other leaks detected when filled with liquid - no pressurized. I was HOPING not to have to braze (and find somebody qualified) and repaint tank and trying epoxy based product method as first (and hopefully only) step. I'm heading out to shop to start sanding paint to see what it looks like bare. I'll post a pic.
Don`t try to braze it yourself unless you have the skills, especially with the thin tank material. It is too easy to burn a larger hole and make it even more difficult to fix it. Good heat control is imperative.
 
Reply
Old Jul 30, 2020 | 03:36 PM
  #10  
Joe12RK's Avatar
Joe12RK
Seasoned HDF Member
10 Year Member
Loved
Community Favorite
Top Answer: 1
Joined: Jun 2012
Posts: 6,144
Likes: 2,547
From: CT/FL
Default

I have an old chunk of what was called gas tank epoxy - it's meant to fix exactly what you have. I might have used it on a car 20-30 years ago, but probably didn't keep it long enough to find out if it held up. Something to consider?
 
Reply



All times are GMT -5. The time now is 05:48 PM.

story-0
7 Surprising Harley-Davidson Products that Are Not Motorcycles

Slideshow: The bar-and-shield logo shows up on far more than motorcycles, some of the company's most unexpected products have nothing to do with riding.

By Verdad Gallardo | 2026-04-29 16:50:35


VIEW MORE
story-1
8 Best Harley-Davidson Motorcycles Ever

Slideshow: Not every Harley gets it right, but these are the ones that genuinely earned their reputation.

By Pouria Savadkouei | 2026-04-15 14:23:21


VIEW MORE
story-2
10 Worst Harley-Davidson Motorcycles Ever

Slideshow: From the troubled AMF years to modern misfires, these bikes earned reputations for reliability issues, questionable engineering, or disappointing performance.

By Pouria Savadkouei | 2026-04-01 20:01:09


VIEW MORE
story-3
Killer Custom's Jail Break Is The Breakout That Refused to Blend In

Slideshow: Killer Custom's "Jail Breaker" build focuses more on stance and visual aggression than mechanical overhaul.

By Verdad Gallardo | 2026-03-18 19:20:32


VIEW MORE
story-4
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?

Slideshow: The Swiss custom shop has taken a Harley Softail and stretched it into something so long and low that it looks closer to a rolling sculpture than a conventional motorcycle.

By Verdad Gallardo | 2026-03-07 16:15:30


VIEW MORE
story-5
Harley-Davidson Reveals Super Cool Cafe Racer Concept

Slideshow: Harley-Davidson's new RMCR concept revives the café racer formula with modern hardware-and it may be exactly the reset the company needs.

By Verdad Gallardo | 2026-03-04 12:23:37


VIEW MORE
story-6
Engraved Rebellion: Inside Bundnerbike's Glam Rock II

Slideshow: A standard cruiser becomes an intricate metal canvas in the hands of a Swiss custom house known for pushing Harley-Davidson platforms far beyond their factory brief.

By Verdad Gallardo | 2026-02-24 18:19:44


VIEW MORE
story-7
10 Motorcycles You Should Never Buy

Slideshow: There is no shortage of great motorcycles to buy, but we would avoid these ten.

By Joe Kucinski | 2026-02-19 14:50:51


VIEW MORE
story-8
10 Things Harley-Davidson Needs to Fix in 2026

Slideshow: Harley-Davidson's challenges aren't abstract; they show up in dropping shipments, shrinking dealer traffic, and strategic decisions that aren't yet translating into growth.

By Verdad Gallardo | 2026-01-13 18:33:17


VIEW MORE
story-9
Southpaw Super Glide: A Left-Hand-Drive 1979 Harley FXE Built to Fit the Rider

Slideshow: Graeme Billington's left-hand-drive Shovelhead is as much about problem-solving as it is about classic Harley form.

By Verdad Gallardo | 2025-12-30 11:27:08


VIEW MORE