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I'm probably going to have these heads blasted and possibly ceramic coated.

I'm guessing i need to take the rest of them apart before i do so.
I've never taken a head apart before...
so my question is how do i remove the 4 spacer and two valve guides?

This bike was a barn find in which somebody reconditioned one of the heads and not the other. I want to take them both completely apart, blast/coat them, then have them rebuilt together.

thanks.
-Josh

NO, no, no. Unless you have the specific tools to cut out for removal of the valve guides, don't touch them. You risk damaging the heads. There are a variety of ways to remove them. Some are risky and many shops don't know what they are doing. Are you even sure that you need new guides?

I'm not sure i need new guides.
Like i mentioned, one head had new valves and guides. The other head is questionable.
Either way, after i am done blasting/coating them, i plan to send them off to be inspected and have new BMW valves put in (i think i am going to shy away from Black Diamond).
I guess i could have my local mechanic check them out?

I'm worried that if i get them coated in their current state, the heat process may be hotter then the typical engine temperature and may ruin the bushings and other items...

Typically, heads run in temperature ranges similar to or exceeding powder coat temperatures. I don't think they will suffer. However, I would not powder coat them, for aesthetic reasons. I think they look fine bare.

Explore soda or vapor blasting (vapor in particular is pretty awesome). Won't damage anything and leaves a nice finish that really doesn't need painting afterward.

There's a shop in the US that takes parts in and does them pretty reasonably (would likely be $15 or so for each head). I'm in Canada and there's nobody doing it here, so I went with soda. No media to worry about after blasting - just wash the parts in hot water to remove any remaining baking soda.

jjwithers wrote:I'm not sure i need new guides.
Like i mentioned, one head had new valves and guides. The other head is questionable.
Either way, after i am done blasting/coating them, i plan to send them off to be inspected and have new BMW valves put in (i think i am going to shy away from Black Diamond).
I guess i could have my local mechanic check them out?

I'm worried that if i get them coated in their current state, the heat process may be hotter then the typical engine temperature and may ruin the bushings and other items...

I would not even consider coating the heads. Why run a risk of over heating? Those heads are of a very good design and work very well as is. Don't mess with it.

A head has a limited life and one can only remove and install guides so many times. I wouldn't want to ever replace a guide that is good. Even if the guide is 1/2 worn out, I would use it to get the last 40 k miles out of it. Heads come off easily and quickly, so why go to all of this trouble to spend money to reduce head life?

I don't get it.

Vapor blasting looks nice and is cheap. Check these guys out:
http://www.vaporblasting.biz

Duane, i hear ya. I made another post regarding the new Siebenrock cylinders and trying to get the exterior of my heads to match the color of the cylinders. That is my goal at the moment.
After that, I'll let a reputable shop assess the heads/guides and install valves/springs. I definitely don't want to do any extra work unless it is warranted. If these heads and guides are OK, then you are correct, why mess with them...

You mention ceramic coating in your first post. Ceramic coating is an excellent insulator; I wouldn't consider coating any air-cooled cylinder head with ceramic coating.

Yeah, i said possibly ceramic coating because i've had a clear ceramic coat applied to a timing cover and it is amazing. It wipes perfectly clean every time i was it. Also, most engine enamels are ceramic based...should i decide to go with an engine paint.

Would a simple 500 degree Dupi-Color engine enamel adversely effect the heat dissipation?

jjwithers wrote:Yeah, i said possibly ceramic coating because i've had a clear ceramic coat applied to a timing cover and it is amazing. It wipes perfectly clean every time i was it. Also, most engine enamels are ceramic based...should i decide to go with an engine paint.

Would a simple 500 degree Dupi-Color engine enamel adversely effect the heat dissipation?

There has been a long-standing debate about whether engine paint will make your air-cooled engine run hotter. In the 70's-80's, painting engines black was very popular, and the mythology of the time argued that the black engine dissipated heat faster. In the last couple decades, that belief seems to have died down - at least the fashion has. I've never seen any real data that proves it one way or the other. You'd think, if it actually did something positive (other than aesthetic), Porsche would have started painting their engines.

The engine enamels you are speaking of are designed for water-cooled automotive engines where reducing the heat radiating off of the engine exterior is not a problem, and can, in fact, be desirable. They are designed to provide a rather thick coating that would not, I believe, be very attractive on an airhead cylinder head. As far as the "ceramic based" nature of engine enamels, while they may provide some heat insulating properties, I do not believe it would compare to the insulating properties of the ceramic coatings being used on headers, such as Jet-Hot, etc..

If you just soda blast that head to get it as clean as possible, I suspect that, over time, the two parts will look more and more like each other. Soda blasting the cylinder as well (to have identical textures on each part) might help to speed that process.