I finally put together the MXS-R and tried to fire up the engine (DLE35) The first couple of runs without the cowling installed worked out great, engine starts at the first/second flip idles nice and accelerates quick and regular with the needle settings recommended by the factory. Problems start when I put on the cowling: engine starts and after 15-20 seconds of regular operations it quits. Trying to restart it it goes for a couple of seconds and then seems to just get flooded (good amount of fuel coming out of the exhaust). Take the cowl off and it works great again, put it on and same exact story. I thought about overheating or pressure build up on the cowl. I did install both plywood panels (the one on the bottom to cover the canister hole and the one on top of the engine mount) and the only holes I made on it are the 2 for the exhaust pipes. Any suggestions?

you need 2 or 3 times the venting as you have intake(frontal open area)

sounds like you have the cowl pretty tight! ya it looks good, but not practical.

it will mess with the air mixture, as well as the pump, the pump relies on ambient air to work right! if you have to much pressure build up in the cowl, the pump won't work right!

I would start by opening up the bottom of the cowl!

I almost always solder or JB Weld a piece of brass tubing to the carb diaphragm breather hole then run a piece of tubing from it to the inside of the fuse through the firewall. Whether it needs it or not, just makes me feel all warm and fuzzy inside The only engine I ever noticed having pressure problems was on a BME 50 with a side carb but since then I just do it cause.

How about closing the 2 side holes? Would that be enough cooling?

You can always try it. Just remember if you overheat that motor you may end up buying another one.
Myself I would rather open the bottom of the cowl than burn a motor up

an "internal combustion engine" is a glorified air pump! it not only needs airflow to breath, but it also needs airflow to cool itself!

that is why the recomended ratio is 3 to 1!

just take some pic's of your sweet cowl, then open it up!

...But it looks so nice....

Try it you got nothing to lose but your plane

After one more day of flipping the prop, cowl on, cowl off, set it richer, set it leaner, clean the carb, prime the pump and nothing... Would not start at all.. Would just burble for a little with the chocke... I was about to give up and send it back when I just decided to pull the spark plug from my pte36 and try it on the dle35.. Well now start at first flip and runs like a clock, cowl on or off.... Go figure!

Yeah the DLE plugs are BS
Thats great news to hear. I can't wait to hear the maiden

Guys,

I just bought this from Tim tonight. Wicked excited... Great customer service.

DonQ