T-bolt clamps, boost leaks, and you

[TSiAWD666]

Hey folks, thought I'd share something I learned last night while pressure testing my car. I use t-bolt clamps I picked up from NAPA a few years ago with my 2.5" intercooler piping. While pressure testing my car (first time in a looooong time, with numerous re-connects of the intercooler piping connections in between) I found I had no less than six major leaks, all at t-bolt clamped connections right around the bolt area. I really clamp down on my t-bolts too, to the point just before they'll start bending my i/c piping.

I theorized that what had happened was that the t-bolt clamp had gripped my silicone connectors and had pinched as I clamped them down in the past, creating a gap that with pressure air would push through. After a bit of thinking I figured if I lubed up the silicone connectors with soapy water and then tightened the clamps down it should help the clamp from catching and distribute the clamping force more evenly. Sure enough this worked and fixed the six leaks.

Now I should say I've just gone and clamped t-bolts without any lubrication in the past and passed boost leak tests. I was pretty surprised at finding leaks under the t-bolt clamps which are supposed to be THE choice for hose clamps. Might be just a bad design with my particular t-bolt clamps that allow this "pinching" too.

So in summary: If you're finding your t-bolts still allowing leaks under pressure, try soaping/lubing the clamped area on your hose before clamping things down.

 

[CanadianTSi]

Very Good Tip.

 

[dsm-onster]

Excellent info!!! This makes sense. It's a great idea!

You know. . . I've found that it is easy to get a t-bolt clamp "cocked" (not exactly perpendicular to the intercooler piping) on the coupling as the clamps are rigid and dig into the silicone. If it is cocked, the different shape presented by the t-bolt clamp (since they are usually much more rigid than a worm clamp) will cause an uneven distribution of pressure around the coupling which will cause pinching like mentioned above, or a point where enough pressure can still press through the connection. Also, this will cause cutting or weakening of the silicone. This happend to me at 25+ psi, until clamping them perfectly perpendicular to the intercooler piping.

A typical worm clamp will flex easier and evenly distribute the pressure around the coupling even if it is tightend at an angle to perpendicular. . . But, of course, the weakness of the clamp itself nulls this advantage. So being sure to tighten a t-bolt clamp exactly perpendicular to the intercooler piping and taking your suggestion to "lube" the clamping surface will insure the most from those terribly *expensive* clamps!