Help with engine placement..sundowner 50
 

Well I have a Sundowner 50 and an OS 91 surpass waiting to go in it. Only prob is those great predrilled firewall blind nuts. They would be awesome if I had a engine that fit but the 91 is going to have to work. Whats the best way to fill those holes and re-drill?

Thanks,
Erik

RE: Help with engine placement..sundowner 50
 

I've knocked the blind nuts out on ARF's then drilled the holes larger and epoxied in dowels. then just re-drill and install the blind nuts to match the new mount.

I would seriously re-consider that engine though. From what I've seen of this plane a .46 2-stroke or .70 class 4-stroke is plenty. The .91 could just end up adding more weight and being more trouble than it is worth.

RE: Help with engine placement..sundowner 50
 

unfortunately its all I have to use. There was one guy in the speed forum that put one on his. He said he just put the battery in the back and it balanced fine. To be honest Im a lil worried about weight. This engine was on my minnow and used quite a bit of tail weight to balance. And the minnow is quite a bit longer. The engine definitely is big for this plane.

RE: Help with engine placement..sundowner 50
 

Maybe you can trade engines with a friend??

RE: Help with engine placement..sundowner 50
 

well Im deep into it now. I punched out all of the pre installed blind nuts and am trying to decide what size dowel to use to plug the holes. Also wood glue would be ok for this no? A few of the blind nuts took some of the inner firewall with it. Do you think laying some 1.5 oz cloth on the inside would help? I currently have some 3/8 dowels and a rod of 5/16. What tips do you guys have? And no I cant get another engine... ;)

thanks, erik

RE: Help with engine placement..sundowner 50
 

I would epoxy the dowels and also smear a little more epoxy of the exposed dowels t fuel-proof them after you sand them flush. I'd personally use as small a dowel as possible but if you have 5/16 on hand that will work.

How much of the ply got knocked out with the old blind nuts? You could just fill the area in with epoxy if it isn't too bad but the glass cloth will definitely make things nice and strong. If you use it, go ahead and put it out to the edges of the firewall and on to the fuse sides. This will help any possible future firewall problems.

RE: Help with engine placement..sundowner 50
 

It didnt take a huge amount of wood with em. It actually took the most wood on the blind nuts I knocked out that I couldnt use anyway. Would epoxy make it tough to get blind nuts to sink back into the firewall? Thats why Im wondering if I should use wood glue, mount the blind nutsm and then epoxy or glass the area. And thanks for your help.

RE: Help with engine placement..sundowner 50
 

Ok another question. How will I know if the engine mounts are in the right place to drill them? For the top and bottom marks I can extend the lines but how about the left and right lines?

RE: Help with engine placement..sundowner 50
 

Ok engine mounted. Just hacked up the cowl trying to get things to fit. Hope to clean that up tomorrow. Also have to go back behind the blind nuts and re inforce somehow. Overall it is going ok. Just hope its not a one flight wonder...:eek: I really think the 91 fills out the cowl nicely. Now I need to pick a spinner. Prob tru-turn ultimate 2 1/4 wide blade. I am praying this thing will fly on sunday. Also any probs running a 3 rd line for fill ups? I would rather not "T" into the carb feed line.

Anywhoo have something for me to read for when I get up at about 2 or 3 pm...:D

RE: Help with engine placement..sundowner 50
 

Just use some epoxy to strengthin area where T nuts are and secure them from turning. Third line is the way to go for filling tank. T in supply line is NOT good. You could also use the Great Plains Easy fueler which is very nice for cowled motors. Some claim they sometimes leak air? could be but I haven't had that happen yet.