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whifof100ll

Well Known Member
I am flying my newly finished RV-6 but have not yet done the finish work on the cowling to seal and block pinholes. My new XP-360 has developed a small oil leak around the forward crank seal. I now have oil weeping out of the external surface of the cowling. I don't know if it has come throught the pinholes (are they normally all the way though) or if it has seeped into the internal glass webbing.

I have less than 100 hours on the plane, and the cowl fit is very nice. I would hate to think that I will have to replace the existing cowl, but I'm thinking that it might be what happens, as filling/ finishing material will probably not stick if it is oil impregnated.

Has anyone had a similar exierience and how did you deal with it?
 
the pin holes are not all the way through, but they will be hard to clean. if i had to do this i would get a siphon type srpayer that you can drop a hose into a gallon of dx 330 (wax grease and silicone remover.) and spray liberally. there are many products that will work. some water soluable. i am not certain of their compatability with epoxy resin. once you get it clean do the vans suggested method of sealing and priming with a layer of resin sanded and repeated then primed with feather fill, k 38 or similar. good luck.
 
I have used this for years to remove oil soaked into balsa model airplanes.

I have never tried it on fiberglass, but I expect it will do a good job.

Good luck.
 
Thanks guys

I have one of those sprayers. Will try laquer thinner first and I think (not sure) it will cut the oil and be safe for fglass.
 
K2R

K2R works great but I have not been able to find it for the past few years. I've tried every major grocery store, Wally World, no joy....

I just had to make a minor wheel pant repair. I started with auto motive degreaser in spray can. Several applications using a course brush to scrub with. Followed with brake cleaner sprayed in. Next I used lacquer thinner to wipe out the area. After drying I sanded with a very course grit paper. Cleaned again. I mixed a small amount of epoxy and micro filler and put a little dab in the area. Came back a few hours later and tried to remove the epoxy. No sign of a bad bond. Carried on with the repair.

I think this process would work fine for the cowl.

Good luck. If anyone finds K2R I'll buy and pay for shipping. I've got a couple of model planes I need to refurbish.
 
Interior cowling finish??

This post got me to thinking about the need to put some kind of oil impervious finish on the interior surface of the cowling. I was just planning on putting on the alumimum heat reflective material over the bare fiberglass. Perhaps more work on the inside cowling glass surface is needed. Thoughts and ideas????

Al Thomas
RV-8A QB
N880AT
Never ending wiring...
 
Cowling paint

I primed and painted the inside of the cowling on my '8' just like the outside. The finish makes it super easy to clean.

John Clark
RV8 N18U "Sunshine"
KSBA
 
glider4 said:
This post got me to thinking about the need to put some kind of oil impervious finish on the interior surface of the cowling. I was just planning on putting on the alumimum heat reflective material over the bare fiberglass. Perhaps more work on the inside cowling glass surface is needed. Thoughts and ideas????

Al Thomas
RV-8A QB
N880AT
Never ending wiring...
Click to expand...

Straight epoxy on the inside of a clean cowl, then the alum heat barrier.

The epoxy will help seal the weave/pinholes, and gives a better surface for the alum to stick to. Gotta get in on fairly smooth, obviously.
 
Epoxy

Acetone, only on fiberglass. Put on a nitrile glove and soak a paper towell with it. Not dripping. Wipe the oily area many times till it comes crystal clean. Then hit the fiberglass with 60 grit paper and then seal it with a thinned epoxy. Thinned with Acetone. Let it cure for a few days and reinstall

Regards
Tad Sargent
7A
Team RV
 
The oil is actually inside the honeycombs

OK, I now have the cowl off and in the shop. After a througough soap and water job, I can see that the honeycomb pockets are dark in some spots. In one small dark spot, I sanded the intertior down to the homeycomb to see if oil was indeed impregnated inside. It is.

I could see how K2R or similar will work with a dirty surface, but here the probelm is deeper than the surface. After the surface is cleaned, oil contained inside continues to weeps out over time.

It seems that my only choice will be to soak the whole cowling in some sort of bath that will leach out the oil or replace the lower cowl.

I'm not sure how to deal with this and guarantee a good finish without replacing the cowl. My plans were to paint soon, but it looks like that will be delayed.

For those of you that have not done so, seal the cowl before you fly!!!
 
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