Red is the colour - Painting a cam cover

Sorting out scabby cylinder head covers

I've been disappointed with my attempts to repaint the original engine covers of my 1991 Trophy 1200. Although I did my very best to strip off all the old paint, I was unable to get every last spec of failed silver paint off of the clutch cover because the casting has some tricky recesses for its retaining bolts. The cylinder head cover (or cam cover, if you prefer) and crank end covers are not as bad but still quite a bit less than nice. Time to do something about it - but how without being off the road?

'No' to being without working wheels; 'no' to scabby covers for Ruby

Dirty scabby sick 2001 engine

Cleaned but no less scabby 2001 engine

The new paint I'd applied to my 1991 Trophy engine has not adhered properly over the old failed paint. Result: new failed paint. Also, the VHT Clear lacquer has gone yellow and started to come away in some places. I used this clear coat over the silver heat resistant paint to get a finish that was close to the original. I now regret trying to repaint this with rattle cans and am going to go for a powder coat instead. However, I don't want to be without my 'triffic Trophy any longer than necessary, especially as the weather has been getting better. So I've been in a quandry about hating the insult of scabby cases that currently adorn my beloved bike and hating the idea of being off the road. Meanwhile, I hadn't done anything with the sick 2001 Trophy engine I'd bought last year, since stripping the top end. So maybe there was a solution here to my quandry?

Borrowed covers

I decided to use the cam, right-hand and left-hand crank engine covers from the 2001 Trophy engine as a temporary measure, plus the clutch cover from by Daytona engine. Yes, another piece of Daytona is temporarily migrating to the Trophy! Even then, the 2001 covers are even more horrible - and would need refurbishing anyway sooner or later. I decided I'd start the process off by working on the cam cover. It is a large casting and, as the picture above shows, had lost a considerable amount of its original black powder coat. I thought it would be a simple matter to shift the rest of it.

Paint stripper is rubbish, wire wheels are harsh and hard work ...

Well I was wrong. I used two types of paint stripper with Scotch abrasive scourers (fancy nylon scrubbers). Despite multiple applications, even leaving the cover in a plastic carrier bag with stripper over night, there were still some patches  that just wouldn't budge. Also, I was left with pitting and quite a number of blotchy dark grey areas in the casting where corrosion had wormed its way into the alloy.

After a lot of work with scourers and paint stripper, most of the powder coat has gone but pits and corrosion remained

In the end I had to resort to a wire brushes and a rotary ginding wheel on a drill and minigrinder (cheap Dremel clone). It took hours. I wouldn't do it again - taking it to a blaster would have been the smart thing to do. Oh well.

Washed down with degreaser

Belt sanding ribs

Ultimately, I was pleased with the finish I obtained although to get rid of pitting I had to remove quite a lot of aluminium from the ribbing that runs across the top. I used a belt sander for that - very harsh but much more helpful than a rotary wheel for keeping the surface flat. A good wash down with degreaser and I was content to get the paint out again. This time, I decided to go red because I had a can in my garage and, as a spare, I am looking at the 2001 engine as an opportunity to experiment some more.

Shiney Red Cylinder Head Cover: Mission Accomplished

After the first coat of red, I could see that the dark grey areas were not covering over very well. I had a tin of VHT Black so I gave the cover a blow over with that as an even colour  - like a primer - to work with and then started again with the red. This time, the red enamel was covering evenly. I built up the coverage in thin layers, each time using a hot air drier to partially cure the paint as I went.



Finally, I decided to use up the last of my VHT Clear. Yes, the same lacquer that had failed on my other covers, Clear lacquer makes such a difference to solid colours I thought I'd risk it. Also, if it does yellow, the effect will be less noticeable over red than over silver. We'll see. 

Red enamel and VHT Clear - a bit of fun

The result looks good to me for now. So I'm ready to swap the cam cover over, maybe this weekend, and to take the originals to a local coater.

Cylinder head cover: from grotty to gleaming

As I wrote in my second blog post, the paint dear old Ruby's engine covers had not faired well from being left outdoors. The cylinder head cover in particular looked like it had the mechanical equivalent of a severe skin problem.

A previous owner had made an attempt to tidy it up a bit with silver spray paint from the timing side but without removing it or the fairing - hence the overspray on a fairing infill panel.

Well anyway, that makes for an interesting challenge, thought I. With all those grooves it's bound to be tricky stripping it clean. So off it came.

I wasn't wrong - it needed three treatments with paint stripper and some Scotch abrasive pads. These pads are a plastic alternative to wire wool. I have found wire wool clogs quickly and rusts in paint stripper. They worked well - it was easy to swill the painty gunge out under a tap and then to rub some more. After a good hose down, I cleaned up some pitting on the embossed Triumph logo with wet-and-dry abrasive paper on a  rubber sanding block.

 Another hose down and then time for paint. I used VHT silver in approximately five light coats (left picture), followed with a two light and then one heavy coat of VHT clear (right picture below).

VHT is heat curing. I knew it would be ages before the bike would be ready for me to run the engine so I *carefully* suspended the cover from a hook in my garage ceiling and then heated it up a bit at a time with a hot air gun. This is a tricky business to do - too hot too fast and the paint will fail and flake off. It all worked out well. I'm very pleased with the finish I have achieved, as hopefully the photos show.

These pictures were taken at different stages of the other work I've been doing with the rest of the bike, especially to do with the swinging arm and rear suspension.