Detailing the Engine: Valve & Timing Cover

Today I spent some time stripping and cleaning the valve cover in preparation for polishing it. I also cleaned-up the aluminum timing cover for the same reason.

I removed the valve cover first. It was held in place by two cap nuts, which I removed using a 15/16″ socket. I then removed the washers underneath the nuts.

Next I removed the oil cap.

Then I pulled the valve cover off and then removed the rubber gasket from the valve cover.

I covered up the exposed head with some aluminum foil to keep out dust, rodents, etc. But first some gratuitous head shots:

I removed the small triangular vent cap by first unbolt the three nuts that held it in place using a 10 mm socket.

Someone previously painted this valve cover a tomato red color. Originally the U20 valve covers came in bare aluminum. I intended to return a more stock appearance to the cover by stripping off the paint and then cleaning and attempting to polish the aluminum cover so it will be shiny. I set-up my work area outside for stripping the paint. I used more Kleen-Strip, which I had previously used for stripping the intake manifold and carburetor heat shield. I began to apply the stripper in one heavy coat using a cheap paintbrush. As the instructions stated, I avoided going back over stripper I’d already applied in order to maintain its seal against the paint.

I coated the entire valve cover in a thick layer of paint stripper. Because it was a fairly warm day (>80 degrees), I covered the stripper with a layer of plastic wrap to prevent it from drying out before it had a chance to work on the paint.

I peeled off the plastic wrap after 30 minutes. The Kleen Strip really worked well–after one application the paint was bubbling off the surface of the valve cover.

I scraped the red paint off using my plastic paint-scraping tools to avoid damaging the aluminum.

I then applied a second coat of stripper to those areas where the paint remained. After allowing it 30 more minutes to work I used a scouring pad to scrub at the painted areas.

After the majority of the paint was removed I sprayed down the valve cover to neutralize the paint stripper. Then I sprayed on some Simple Green to clean the piece.

I scrubbed the valve cover with another scouring pad and then rinsed off the cleaning solution.

The next step was to begin the polishing process on the valve cover. For this I sanded the piece using 320 grit, 400 grit, 600 grit, 1,000 grit, and 1,200 grit sandpapers. Since I was wetsanding, it was very important to continually spray the part as I was sanding to rinse away the fine particles coming off, otherwise the sandpaper could become clogged and become ineffective. For this reason I used my parts washer, with plain water, to continually spray water on the part to keep it clean.

After several hours of sanding with progressively finer grits of sandpaper the valve cover was becoming cleaner and more shiny.

Then I went to work on the timing cover on the engine. I removed the front inspection cover first. I used 10 mm and 12 mm sockets to remove the bolts holding it to the head.

Then I removed the cover and pulled the gasket off the inner edge. I will replace this gasket when I reinstall the inspection cover.

Then I removed the water pump from the timing cover. Initially I wasn’t planning to replace the water pump, but the shaft where the pulley mounts is fairly rusty and I’d rather replace it now while the engine is out of the car. I unbolted the water pump bolts using 12 mm and 13 mm sockets.

I removed the water pump, which I will replace.

I made a plug out of a ball of masking tape to stuff into the water inlet hole to prevent any water or dirt from getting inside.

Underneath the water pump was an area I was unable to access to clean before the pump was removed. I sprayed this area, scrubbed, and rinsed it clean.

Then I wetsanded the timing cover, continually spraying it with water to rinse away the dirt coming off. After working through all of the grits (320, 400, 600, 1,000, and 1,200), the timing cover was fairly shiny.

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