How to respray valve cover

[roxburd]

Hi,


I'm doing a major service and when I got the valve cover off I realised that the paint is all coming away - currently it's just bubbling away on the top where it doesn't show but obviously, it'll creep round to the ends and start to look really bad.


So I thought I'd respray it but don't know where to start - what material is it made of? Aluminium? Some exotic magnesium alloy?


And what's the right way to spray it - some special primer?


Obviously it'll need preparing well as it'll be badly corroded where the paint is bubbling up. I'd plan to attack that with wire brush attachments on an angle grinder unless the alloy is too soft???


Also, is there anyone who reconditions these that anyone can recommend? If he's cheap it might be worth it...


Cheers!!
Dave

[devilsyam]

Took mine to local grit blasting shop got it blasted then sprayed with simoniz silver and baked in oven worked a treat

[roxburd]

Took mine to local grit blasting shop got it blasted then sprayed with simoniz silver and baked in oven worked a treat

Nice one - sounds like just the job.

[bludclot]

a grinder attachment wire brush will remove all surface material and the actual aluminium of the cover if left / pressed too hard and will leave score marks which then require sanding out or filling (then sanding). better to use a paint removal pad such as this:
http://www.ebay.co.uk/itm/2-x-Paint-Rust...58c978ca3a


likewise blasting can leave a pock marked finish if done with a harsh medium or performed without care. after blasting the inside of the cover will require meticulous cleaning to ensure all media is removed.


chemical dipping is the preferred method of paint removal as it leaves the aluminium intact. this can be replicated at home with wire wool and parafin (or similar) but is painstakingly slow.


rather than any of these a bucket of water and some wet'n'dry will produce good results. 400 grit for starters should be fine unless corrosion is really bad, keep it soaking wet and rub away until the entire outside surface is smooth. complete paint removal is not necessary. 400 will also leave scratch marks, ideal for primer adhesion. dry the piece thoroughly, wipe with pre-paint / panel wipe, dry again and wipe with a fresh tack cloth before spraying with primer. i would recommend the pro-xl range:
http://www.ebay.co.uk/itm/Pro-XL-Super-H...1a06b14882


two coats of this will give sufficient depth of paint to allow sanding back without sanding through. allow at least 30 minutes to dry but ideally 24 hours then hit it with 800 or 1000 grit (gently - let the paper to the work always) until happy with the result and then repeat the prep process before praying at least two top coats of simoniz:


http://www.ebay.co.uk/itm/SIMONIZ-MOTORC...519ba429bd


with care and attention to detail a factory quality finish is achievable. for a piece like this i would tend to stand it on two aerosol lids on the inside of the underside so that no edges are flat to a surface. i would also mask all holes and the underside carefully. your chosen environment will affect dust/hair levels greatly - consider vacuuming the shed/garage and settling dust with a sprinkling of water on the floor where paint will be applied, particularly the colour coats. hanging the piece so that the main surface is vertical also helps with this but makes spraying more difficult. temperature affacts results, 21 degrees is ideal, more is fine but less can lead to cloudly finishes and poor adhesion. don't lay down too much paint in any one session, build layers carefully. and finally - wear the best mask that your can find / afford!

if you want me to paint it i can. hth.

[shrekster]

I just sanded mine by hand and sprayed with rattle cans form Halfords. Ford Starlight silver is a very close match to the original colour. I was worried it wouldn't last due to the heat from the engine but I did mine over 3 years ago and it still looks perfect, makes me wonder what Cr*p Yamaha used in the first place.
I'm.

[roxburd]

Wow. Well, thanks to all of you - so many options!


Thanks particularly for the links - makes it almost a two-click job... apart from all the rubbing, scraping, wiping...


Think I'll play with the wire wool and wet & dry until it looks reasonable and then bang some Simoniz on it. Then when it looks sh1t I'll ask you how much you'd want to do it properly, bluclot :-)


Cheers,
Dave

[slimwilly]

Took mine to local grit blasting shop got it blasted then sprayed with simoniz silver and baked in oven worked a treat

was that  "gas mark 7 for 30 mins  :lol