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Getting oil drips out of an unfinished cowling

Thermos

Well Known Member
Patron
A question for VAF fiberglass experts -

I've been working on fitting my lower cowl, and it's been staying on the airplane for a few days at a time. I didn't notice a few, very slow, oil drips from somewhere on the engine and now I've got some oil stains on the cowl. I had always planned to seal the cowl interior with epoxy, but I'm assuming that I need to get as much of the oil out as possible before I do. Any suggestions?

Thanks in advance,

Dave
 
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I've used Coleman fuel as a de-greaser and it seemed to work well. Keep blotting it with a clean saturated rag. Then get epoxy on it while its clean.

As a side note, I used left over epoxy to thoroughly coat the inside of my cowl. Then I used white high-temp gloss engine enamel. The system has held up well although I only have about 90 hrs. on the plane. There are always better way$.
;)
 
I used laquer thinner on a saturated rag, seemed to do the trick. I've epoxied over the area now and it seems to have stuck.


Alex
 
I've used Coleman fuel as a de-greaser and it seemed to work well. Keep blotting it with a clean saturated rag. Then get epoxy on it while its clean.

I used laquer thinner on a saturated rag, seemed to do the trick. I've epoxied over the area now and it seems to have stuck.
Alex, Sam -

Thanks, I've got some of each and give them a try. Glad to hear that the epoxy stuck well over the cleaned area.

Best,

Dave
 
K2r spot remover or fuller's earth will draw the oil out. Using a solvent will tend to wash some of the oil in deeper.
Stewart Willoughby, 6 panel.
 
Acetone

I recommend acetone. Wipe it on with a saturated rag and then wipe off the residue with a clean dry rag. The acetone dissolves the oil and the dry rag removes the oil along with the acetone. If you let the acetone dry, the oil will still be there.
 
Agree with the k2r Dave. I used it in my RC days to get oil off of balsa wood prior to covering when doing repairs.

Not that I ever had to actually *do* repairs since my RC piloting skills were so superior that I never crashed..... But if I *would* have, I might possibly have used k2r.......

:rolleyes:
 
Not sure what you mean...?

Dave, I think he is suggesting that the oil cooler is the source of the drips?

Anywhooo... all these are fine suggestions. I have never found anything that removes the offending product completely.

If you coat the inside of the cowling with primer, it many not seep in so deeply... or it will give you another layer for the stain to seep through. The porosity of the primer still will allow penetration. At least you could remove the primer and have less of a stain???

:cool: CJ
 
prep-sol

Another solvent that works better than Acetone is Prep-Sol Wax and Silicone Remover. Auto body paint stores carry that. Once again, you flood the area to lift out the grease and then immediately wipe the stuff off with a clean, dry rag.
The basic idea behind these cleaners is simple, they are designed to lift the contaminant up off the surface long enough for you to wipe it away. The surface MUST stay wet and HOLD those contaminants up in the cleaner for you to wipe off with a clean/dry rag. That is mistake most make, they let it dry and the contaminant ends up laying right back on the surface.
Clean several times to remove heavy contamination. Also, You clean first, then sand. Otherwise you will just sand the contaminants down into the weave of the fiberglass and get a weak bond with the epoxy.
 
Another solvent that works better than Acetone is Prep-Sol Wax and Silicone Remover. Auto body paint stores carry that. Once again, you flood the area to lift out the grease and then immediately wipe the stuff off with a clean, dry rag. Clean several times to remove heavy contamination. Also, You clean first, then sand. Otherwise you will just sand the contaminants down into the weave of the fiberglass and get a weak bond with the epoxy.

All great advice! LIFT contamination to REMOVE it.

If you do prime and you get contamination on the primer, clean, wash and wet sand prior to re-coating is the route I would travel.

:) CJ
 
Washer and dryer...

After I smeared any and all leftover epoxy from any fiberglass work on the inside of my cowling, I applied 2 good coats of rattle-can white epoxy appliance paint. Rock-hard and cleans easily.
9 months, 100 hours...no blistering, peeling or scorch marks. :)
 
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