Firewall Forward Work Continued

TIme: 3hrs

I had a productive day today getting a few things done on the engine. I worked on putting together the exhaust shroud for the heater and also finished up the radiator/oil cooler bracket. The exhaust shroud needed all the holes drilled in the large clamps that hold the shroud cover onto the exhaust. There’s quite a few holes that need to be drilled, but once you get set up it goes along quickly. I used RTV to seal up the mating surfaces and also filled the area where the inlet and outlet tubes attach to the shroud. I’m waiting on the bolts and a longer tube for the front (the one I had was too short to reach past the cowling.

On the radiator/oil cooler mount I just needed to install the cam locks. I’ve been getting the hardware from Skybolt. I purchased a simple non adjustable, non floating receptacle and had a few of the -6 length studs already. I just need to put some kind of rubber on the part that presses against the oil cooler so it doesn’t wear and scratch the cooler.

Oh yeah and also my Andair fuel check valves came in so I test fit them into the fuel pump assembly. It’s tight but they fit. I had to order these from Andair in the UK since they seem to be the only ones that have the check valves with the 5/16″ hose barb.

All the holes drilled in the exhaust shroud. The last row of holes needs to be after it’s fitted onto the exhaust when the clamps have been tightened. TAF supplies stainless steel rivets with a steel mandrel to use on the shroud.

A few photos of the shroud installed on the exhaust. I order some 1.5″ (0.065 wall) anodized aluminum tube for the front inlet. I needed a bit longer tube so that it will stick out from the cowling (will need to cut a hole in the cowling for that) Also to get the shroud on I had to remove the bracket that attaches to the exhaust. You just need to remove one of the engine mount bolts and an M10 Allen screw to get the bracket off.

Radiator and oil cooler brackets are done. I had to modify the camloc receptacle a little so that it would fit flat on the bracket. I just had to file one edge a bit.

Well it all fits. The sides of the box bow out slightly, but should be fine. And yes I know I have the fuel pumps reversed (I think I have the check valves in the right direction, but I’ll check it out before I install them). It seems like they fit better in the box this way and the box is labelled “in” and “out” so I wanted to make it so the labels are accurate. It shouldn’t really affect the hose braided lines.

Coolant Hoses

Time: 1.5 hrs

I ran the two coolant hoses to the radiator. The left side may be cut back more once I get the exhaust installed and see if there is a way to anchor the hose to the exhaust. The left side also involved using and 45 degree hose since the angle was a bit too much for the super flexible hose that I’m using. On the right side I was able to directly connect the hose to the radiator since the hose was at a good angle to connect to it. The hose I’m using is really flexible and is made from silicone. It meets the requirements in the Rotax manual and ¬†seems to be very high quality hose. I’m really impressed with how well the hose is able to bend and not collapse. I put some thermal sleeve on the parts of the coolant hoses that run near the exhaust. The exhaust is also wrapped so hopefully it won’t get too hot. The sleeve looks a bit nicer then the thermal wrap, but it’s kind of a pain to put on and if the hose bends then it’s even harder. If I did this again I’d probably do the wrap rather than the sleeve.

Photo of the right side hose. I was able to run it directly to the radiator without having to use a 45 or 60 bent hose. I anchored it to the clamp that holds the large air intake to the turbo using an M5 nut and a bit modified adel clamp. I modified a longer adel clamp by cutting it a bit shorter and drilling a new mounting hole on one end. I suppose I could have just bought a larger clamp, but I had a large clamp that I wasn’t going to use. The clamp helps keep the hose a bit farther from the exhaust and provides some strain relief on the connection to the radiator.

The left side hose is quite a bit longer than the right and I had to use a 45 bent hose to connect it to the radiator. I’ll probably end up cutting this hose a little shorter once I see where I can anchor it. I have one anchor on the vertical portion using two adel clamps tied to the white engine mount. Note: I’m going to redo the clear tubing for the overflows with a Y fitting instead of the T to get a better downward flow.

Photo of the join to the 45 degree bent hose. The join is made by using a short piece of aluminum tubing that fits inside of the silicone hose.

Misc Work

Time: 1.5 hrs

Just did a few miscellaneous things today:

  • Drilled 6mm holes for radiator
  • Added neoprene around edge of radiator mount
  • Fixed hinge on rear seat (I had it backwards)
  • Filled/sanded some rivets
  • Fixed small crack in nose wheel pant

I really need to get the parts from TAF that I order back in December. Once I get those I can finish up a lot of the engine items. I’m also waiting on the oil cooler from California Power Systems.

Added some neoprene to the edge of the radiator mount hole. Also drilled the holes for the M6 bolts.

Cut down some M6 bolts and screwed them into the radiator. The new radiator has rounded ends and the cowling seems to have been updated to fit the new radiator.

I’m wondering how difficult it’s going to be to get the lower cowling off/on with the radiator and oil cooler mounted. There will be a bracket that connects the two and then some camlocs will hold them to the cowling along with the 2 M6 bolt pins (above). It seems like it will be a bit of a challenge to get all the lined up when putting on the cowling.