This is a good little Sunday job, you'll need a scraper, sandpaper, a roll of 1in masking tape, newspaper, hot air gun, some compressed air and a tin of wrinkle spray. Oh, and a scruffy Lancia Delta inlet manifold!
A Lancia Delta's inlet manifold paintwork can look as scruffy as the cam cover. Although the cam cover is quite simple to remove for a refurb, removing the inlet manifold is a terrible job.
I have a car here that needed its rough looking inlet airway refinishing, I decided to try painting it in situ.
I opened the plastic pipe cover and held it forward with some masking tape, I released one end of the strut brace, loosened the other, and swung it up out of the way, then I got to work
Not the bottom of a tramp's bed!
The top of the inlet tract is visible, but the lower parts and pipework can't really be seen, and as they're out of the way the paint doesn't get damaged, so you only need to paint the top.
I scraped off the loose flaking paint, then rubbed it all down with 40grit paper, then again with 120grit to feather the flaked area edges. Then I blew all the dust away with the air line gun.
There's a raised moulding along the back of the airway, this is good to mask on to, so stick a line of 1in masking tape down this line and then down the front edge too, and cover the bright alloy mounting brackets under where the flap closes.
Carefully mask up the throttle body where it meets the inlet, then wrap the body in newspaper and tape it up. Do the same for the other end, carefully stick the tape to the edge of the bright metal fitting, you can pull the top pipe off the fuel pressure sensor if it's in the way. Take a page of newsprint, and on a flat surface run half the width of masking tape right down the edge. Take this sheet and stick it to the masking on the back of the inlet, and do the same again for the front.
Then stuff everywhere with newspaper and put a dust sheet over the windscreen and scuttle areas, cover the engine and wing tops too. The paint will go everywhere.
Give the raised silver strips a good wipe, then stick a single thickness of masking tape to them, press this down well. Take a sharp blade and carefully run it down the edges of the raised strips, this will cut the masking tape in a line at the raised edges, Rub it down firmly again, then pull away the tape that's not required.
Give the area a light dusting of etch primer, then dry that with your hot air gun.
Shake your can of wrinkle spray, then give the whole area 2 or 3 light coats, when that's done gently warm it all with the hot air gun until it goes dry and wrinkly. The paint will take a good while to dry and start wrinkling.
This is the wrinkle finish I use, others are available, but I haven't tried them.
Now, a quick lecture...'Dusting' is a painting technique where very light coats are sprayed on to a surface. Because spray paint is very thin it has a high solvent content, the large quantity of solvent in a heavy coat of paint will attack the sub surface. Dusting is building up a paint finish with very light early coats, then getting a bit more generous at the end, when the early coats have dried and sealed the delicate sub surface. You should use this method here, solvent will attack and curl up the exposed edges of the flaked off powder coating. You don't want this, so take your time, use a bit of heat between light coats, and build up the finish slowly.
This is good for the final finish too, a light coat will give nice small wrinkles.
After painting, leave the job alone for an hour, then return and pull the tape off the raised stripes, you'll enjoy this!
Carefully remove the rest of the tape and newsprint and chuck it all in the bin. You can put the strut brace back in place, and the plastic flap over the injectors.
Job done! I was pleased with the result here, and it saved an awful lot of work.
I forgot to photograph the flaking paint
before doing this job, but it looked bad. This operation needed doing, the paintwork was poor, these results are easy to obtain with a little care, and some patience.