I'm back with some FD tech: Turbo Coolant Line Fix

Recently my brother dipped back into the world of racing and a project car in the form of a FD Rx-7.

Driving around town we'd slowly loose coolant. Fearing the worst we started doing research to find solutions besides the infamous coolant seals. It seems that there is nothing easy about the FD cooling system. Special bleeding procedures, air separator tank and coolant lines prone to failure.

Long story short, after much troubleshooting it turned out one of the lines that supplied coolant to the turbo had a leak. After removing the oem rubber pieces we decided there must be a better solution. Having a Summit racing distribution and retail center down the road didn't hurt with our decision to experiment.

Not finding the info we needed, in the detail we needed, I decided to do a brief write up for those interested. Each car will vary, because god knows most Rx's have been modified by this point, but it seems the ideal amount of prep we had was removing the top intake tube, intercooler, and the radiator hose that comes off the filler neck. We tried with removing less in our laziness. But the removal of the intercooler and radiator hose took it from frustratingly impossible to very easy. Maybe just because it was our first time changing these lines and we had to see what we were doing, but if you're reading this, chances are it's the same for you as well.

For roughly the same price as oem pieces shipped we got Mishimoto hoses, Comp clamps, and Thermo-Tec 2000 degree sleeve. For the lower hose a trip to Autozone for part number 18031 provided the perfect crimp free, preformed line with the tight 90 degree bend we needed.

The failure my brother experienced looked like it could be from the age and heat cycling of the oem rubber piece, but it also looked like the snap clamps, or damage to them from installation with needle nose pliers. Either way it was a few tiny, almost imperceptible holes and tears allowing coolant to leak and burn on the turbo or hot block.

Either way with the Mishimoto lines rated at 330 degrees and the Gates hose at 275 I felt we were in the territory of the oem bits. We cut the Thermotec tubing about .5" longer than the lines on each side figuring the overhang would help, and with three feet of it to use, we had plenty to spare. The Thermotec tubing is rated at 2000 degrees, who know how much it blocks out. But realistically, if it allows the rubber to last one season of racing the car we'd be happy.

I'll post results, but I feel the photos will speak for themselves. Not only is the leak resolved, but I have a feeling we won't have to worry about these lines for a while.