Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help

Go Back   PeachParts Mercedes ShopForum > Technical Information and Support > Tech Help

LinkBack Thread Tools Display Modes
Old 06-04-2003, 11:26 PM
Registered User
Join Date: May 2001
Posts: 161
"103" valve cover need re-painting, what to use ?

My valve cover (black paint) is about 20% flaked off and looks really "ratty". It was like that 3 years ago when I purchase the car so I removed what was left of the paint and primed it with etching primer and painted it black again with engine enamel. WELL, what do you know, it started to come off in 1/4 inch size chips again!!

I need some advise on what products WILL work and stay on and/or what cleaning methods will prep the metal to accept the primer and paint.

I'm ready to do the job again , but not every 2 or 3 years. Something should stick to the covers. ??


Reply With Quote
Old 06-04-2003, 11:27 PM
MTI's Avatar
MTI MTI is offline
Registered User
Join Date: Nov 2002
Location: Scottsdale, Arizona
Posts: 10,626
Clean it (or have it cleaned) then have it powder coated so you won't have to paint it again.
Reply With Quote
Old 06-05-2003, 01:11 AM
Registered User
Join Date: Mar 2003
Location: Southern California
Posts: 2,055
The original (thick) coating appears to be a plastic, which was probably intended to attenuate valve train noise. With heat/time it tends to bubble and lift and look ugly.

Aluminum requires some special preparation to ensure adhesion of a paint finish. The first step is to chemically strip the paint or other coating and then mechanically clean the surface with a soft media (bead blasting) so as not to unduly change the surface texture.

Go to an automotive finish supply store and buy a bottle of "Alumiprep" and "Alodine". Alumiprep is a mild phosphoric acid solution that etches the surface of aluminum to remove oxidation. Follow this up shortly with the Alodine, which reacts with the surface to from a chromate compound to prevent oxidation. Follow the directions on the bottles for dilution and dwell time. Immediately after drying the part following the final water rinse to wash off the Alodine, paint the cover with a flat or semigloss engine enamel.

If you're not sure if you want flat or semi-gloss, buy both and start with the flat. If you want more sheen, just consider the flat to be a "primer" and top coat it with the semi-gloss. I prefer the flat and then coat it with a 50/50 mix of Armor-all and distilled water from a spray bottle and work it in with an old natural bristle paint brush.

The Alumiprep/Alodine process is what is used to prepare aerospace aluminum structures for painting.

Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -4. The time now is 11:23 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page