Painting Inside Fenderwells

[ctaylor738]

I did the nasty job I have been dreading this morning - cleaning the engine compartment of the 280C with degreaser and a pressure washer. For a low budget effort, it looks pretty good.

I would like to spruce up the engine compartment before installing the engine by painting the inside fender wells. I do not have a spray gun, but I have found a place in Hemmings that will provide MB paint colors in spray cans.

Any experience or advice on this?

TIA

Chuck

[Tom Drew]

Chuck- I can pass along some insight on this as I have just completed a similar project on my 108. The most important component of a quality paint job is proper preparation of the existing surface. This consists of two operations: (1) Cleaning & (2) Sanding. In general terms, we want the surface absolutely clean first, then we want to sand it to provide the necessary "tooth" for the new coating to adhere to. Specifically, absolute cleaning means that all traces of dirt, grease, wax and silicone are gone. In your paticular case, I have found that most degreasers, either water or solvent based, always leave behind a greasy film that inhibits paint bonding. I prefer to use either an aerosol brake cleaner or acetone from the beginning, or as a final cleaning after the use of a degreaser. You can also use products
from the automotive paint suppliers (PPG, DuPont, etc.). Each of these suppliers makes its version of a wax-grease-silicone remover and all are excellent, the only downside is that they tend to be somewhat expensive. All this attention to cleaning is so that we don't grind dirt/grease/wax into the surface as we sand. Ideally, we want to sand the surface with the grade of sandpaper that will provide enough adhesion for the new paint without showing sanding scratches through the final coat. If we don't sand the surface we are going to paint, it's not a question of if the paint will flake off, but when! As to your inner fenders, here's the procedure to follow: (1) Clean as discussed above. (2) Sand surface with #320 wet or dry paper & use a 3M Scotchbrite abrasive pad on areas that are rounded or difficult to do with the paper. (3) Prime any areas that you've sanded through to bare metal with an aerosol "sandable" type primer. Allow primed areas to dry and sand them as above. (4) Final clean with an aerosol glass cleaner (DIRTEX brand has worked for me) & a lint free rag. (5) Paint. A few guidelines for painting w/ aerosols: The thinnest coat of paint that will cover & provide good gloss is what we are striving for. Overly thick coats of paint won't last as long because they are not flexible and can't move with the metal, leading to chip & crack failures. Your first coat of paint think of as a "tack coat". Don't try to cover completely with this first coat but don't go so lightly as to get a "frosty " appearance. Let this coat dry until tacky. You can test this by touching an adjacent masked area. Your second & succeding coats should go on heavy enough to provide a uniform gloss but not so heavy as to form runs. This is of course best achieved by practice & experience, like so many other things in life! Lastly, be careful & patient when you're masking. Nothing is worse than putting down a great paint job & having alot of paint where you didn't want it! If you are a "how quick can I get this done" type, you will really have to keep those impulses in check! Hope this helps w/your project.
Cheers,
Tom

[ctaylor738]

Tom -

Thanks for the advice. I will follow it. I just got a note that Paintscratch shipped the paint today. Will keep you posted.

Chuck