Time: 1.5 hrs
Today I wrapped the 4 exhausts running between the cylinders and turbo with Design Engineering 2″ thermal wrap. I had read on the Rotax blog that guys are wrapping the exhausts and haven’t had any negative affects…yet. Also Torrance TAF is wrapping the exhausts on some of the planes their building so it seems safe to do.
The process of wrapping the exhaust was pretty easy. I first cut 2 5ft and 2 6ft lengths (the right side pipes are a bit shorter than the left) of the warp. I did one overlapping wrap to start and then you maintain (or try to maintain) a 1/4″ overlap as you wrap the material around the exhaust. You don’t want to over do it because you could end up putting on too much material and cause too much heat to be retained in the exhaust. I wrapped the 4 main pipes down to where they meet at the turbo. I then did some creative wrapping to try to get the best coverage over this area. It took some experimentation, but I think I got a decent wrap around it. The wrap ends are held down by some stainless steel ties. I’m thinking now about how I will wrap the turbo. The guy at Torrance TAF said he was going to use a 3″ wide piece of wrap to cover it, but I’m not sure how you secure it, I guess you could run some wire through the edges and tie the ends together to form a kind of doughnut. I also saw that you can purchase a boot that is custom made to fit around the turbo, but they’re pretty pricey (like $150) and I saw that some fall apart so I’ll have to think about it.
One tip is if you’re sensitive to fiber glass wear some gloves. It doesn’t bother me so I didn’t wear any, but you’ll definitely get some glass on you if you don’t.
First pipe wrapped. I used a temporary zip tie to hold the end, but it actually stays fairly well with out it. The trickiest part is getting it started after that it goes quick wrapping down the pipe. I tried to hold some tension on the material as I wrapped it around the pipe. It stays wrapped pretty well.
All the pipe are wrapped. Only the area where the pipes all meet before going into the turbo needs to be wrapped. I secured the end with stainless steel ties. I also left the front EGT sensor bolts accessible so if I need to use them I don’t hav the cut the wrap.
This area took some time. I didn’t;t want to over wrap it, but the way it’s shaped makes it hard to wrap it so the wrap wants to stay. I secured it with a few ties.
Close up of the tie. The worst part is that the ends of the material want to fray after you cut it. To do a nice looking job you have to hide the ends. When you start you can do one full wrap to cover the end. When you end you can’t do that so I ended up folding back the frayed part under to hide it.