IC hose popping off...again...
 

I have a 97 with an fmII kit running the 2560 turbo and a hydra. The intercooler hose that connects to the turbo outlet keeps popping off under boost, used to be 13psi, now its 8psi or less. I tried different hose clamps, even the expensive ones that FM sells, i also tried using hairspray to make it tacky. The connection points are cleaned of all oil and residue before assembly. I have even tried tightening to the point that i almost broke the clamp(which broke after i tightened it more during another trial) A friend suggested high temp RTV sealant . Not sure if i want to use it or not. What do you guys suggest? Have any of you guys upgraded the piping from the fmII silicone hose? If so how did you route it?(pictures?) Thanks again for the help

Call FM

About 5 or so years ago we had a small batch of turbos that didn't have a bead machined into the compressor outlet. Perhaps you have one of these? The solution was to remove the compressor housing & create a bead. If you have a bead & a proper connection (and it's not oil fouled) there's no reason it should pop off at boost levels anywhere near that.

i have one of the turbos without the bead...:mad:
i will call you guys tomorrow

Best thing is to find a local guy who can weld aluminum & have him tig weld a small bead around the tip. We can do it but it'll increase your down-time quite a bit.

can you post a picture? I'm just curious what it looks like

Kinda like that... just a straight outlet without a lip on it.

https://www.miataturbo.net/attachmen...ine=1371144426

You need to get the ribbed kind for more holding satisfaction.

Here is a trick that works all the time. You have to scribe circumferential grooves in the outlet. Use a carpet knife or similar to make a few passes. Try to get them parallel and somewhat deep. This will create sharp ribbing that the piping will grab onto. You can't really hurt the aluminum unless you can scribe with the strength of 10 ordinary men. I prefer this than the swaged lip that some tubing ends have. The ribbing allows for maximum surface area for the clamp. I've even used it on a plastic tube where you could not put much clamping force and it worked great.

If you want a picture just google "water slide joining ridge scalped my entire back off" to get an idea. I'm sure youve experienced that at one time or another.

I googled this and found no good results.

Since the lip needs to be added to the cold side, why not build up a lip with thickened epoxy (eg JB Weld)? It's cheap and easy to work with and should hold up just fine at the temperatures and pressures it'll be subjected to.

Sorry it's here with images and such:





sports-report.net/piperibbingIC

Mine used to do the same with hose clamps...

I have it fastened with dual T-bolt clamps now...its not going anywhere... local parts store should have them for less then 10 bucks each.

Reference (hose clamp) BAD:
https://www.miataturbo.net/attachmen...ine=1371150987

T-Bolt clamp GOOD(you should be able to fit 2 on the hose):
https://www.miataturbo.net/attachmen...ine=1371150987

I wouldnt expect you to have an issue with Tbolt clamps on that. none of my intercooler piping is rolled and I've not have anything blow off yet. I am only running a measly 10psi though.

12 PSI here, no popping off, worm clamps tight as a male virgin.

I had one of the early FM11 kits also and was blowing that same hose off after a couple years of having no problems. I tried everything and couldn't keep it on and then found that one of the bearing cooling water lines was very slightly dripping on that area and the anti freeze was making it slick. Replaced the rubber lines with new ones and the problem went away.

Ditto to this. I have a few pipes on my daily driver that aren't rolled.


They've held 25psi.

Clean everything up, get a clamp worth a shit on there, and roll. You MAY need to replace the coupler if it's fucked up or worn.

+1 on the t-bolt clamps. You should not have ANY issues if using one of those torqued down. Also, hair spray on any connections. I use the "freeze it" brand like this:

https://encrypted-tbn1.gstatic.com/i...jiJCXDJaSM-KIg

The stickier and gnarlier the hair spray the better. This stuff dries like glue and is seriously hard to pull the coupler off after a few heat cycles.