The Two-Second Trick That Seals (Nearly) Any Banjo Fitting

How many times have you had a crush washer that won't seal up? Often they're copper and get work-hardened from the stamping process, and not everyone remembers to anneal them. Plus you're not really supposed to reuse them, so once one is installed and leaking, you kind of have to start over with two new crush washers. 

Here's the hot ticket to stop leaks dead in their tracks. Snug up the banjo bolt as you normally would. Walk over to your box, grab your hammer, and smack the end of the banjo bolt right on the hex. You don't have to crush it, just a hard tap does the trick. Then torque the bolt to spec. This helps the copper conform to the deformities in the bolt's shoulder, the banjo fitting on the hose, and the item being sealed.

If you want to try it without the torque wrench, snug up a bolt to where it's "tight" by feel to your hand. After the hammer smack, you'll usually get another 90° or so of easy rotation since the crush washer has now been crushed.