Oven Cleaner Nightmare

[Dhide371]

I have my CB350 down to nothing and was working on the valves last night. Had the great idea to clean the carbon out with oven cleaner before I removed the valves. After valve removal the anodized layer has vanished from my gasket surfaces leaving me with bare aluminum. Is this garbage now??? I'm an idiot.

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[frogman]

Should be bare aluminum there's no anodizing on the heads.

 

[danker16]

the no anodizing on the head..the black stuff on your head is baked on gasket material.. wear gloves, i used scotch brite pad, a razor blade and lots of brake cleaner

 

[VonYinzer]

Do you have a proper repair manual?

 

[Dhide371]

Yes and all the gaskets and everything else. I'm just fighting this gasket goo with everything I got. I'm losing


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[NobleHops]

Oven cleaner is a caustic and you can't leave it on there. It will (is) dissolve the aluminum. You need to neutralize it ASAP. Vinegar will do the trick. Then you need to rinse THAT off thoroughly as it will eventually darken the aluminum.

Get what you can off with rags or paper towels, scrub it with soapy water, rinse it, and then soak it in vinegar. Rinse that well.

If you haven't lost metal I can fix that. Hit the links in my signature if you are interested. That will take an hour to make look perfect again.

 

[Dhide371]

I did just as you said and then soda blasted. Looking a lot better. I stayed away from the gasket surface and valve seats tho. Is it advised to have the gasket surfaces machined while off? Look pretty clean to my naked eye but u know how that goes. Thanks for the input


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[VonYinzer]

Soda blasting won't hurt gasket surfaces. You shouldn't need to machine them unless they're damaged.

 

[Dhide371]

Really? I'm so scared to blast the gasket surface from what I've read the surface seems to be an egg shell


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[NobleHops]

Really? I'm so scared to blast the gasket surface from what I've read the surface seems to be an egg shell


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He is 100% correct, that is part of the beauty of soda blasting - it won't remove any metal at all. Blast away.

Very glad to hear you got it squared away. I've had a few of those moments myself for sure.

 

[frogman]

Gasket surface is just a machined part of the head, there is no "eqq shell" you can cut through. It's just as soft as the rest of the head though, you can scratch the hell out of it with a scraper if you are not careful.

Personally, I use chemical removers to get rid of the old gaskets and a scotch brite pad to clean the harder to get stuff off. Then its into a bath of Simple Green and water to help loosen at the crap on the outside.

 

[Dhide371]

Looks like that oven cleaner got the best of my surfaces. Here you can see a picture of the pitting.... Order a new head or bring this to be machined and vapor blasted? I already have a soda blaster in the shop

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[NobleHops]

Looks like that oven cleaner got the best of my surfaces. Here you can see a picture of the pitting.... Order a new head or bring this to be machined and vapor blasted? I already have a soda blaster in the shop

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A skim on a mill with a flycutter will help it seal for sure. The vapor blasting will restore the finish, assuming there's not too much metal missing.

On a SOHC Honda the head and rocker cover are a set. You will probably be better served giving this a skim and a blast. I can handle all that if you want help, hit the link in my signature if so.

 

[frogman]

I've seen worse and I have a hard time believing oven cleaner did ALL that. That is the reason why gaskets have sealing compound in them which makes them such a PITA to get off. That damage could have been there years before you started into things.

Now, skimming the head will change the cam height which will lengthen the chain which will effect the timing slightly depending on how much they take off just FYI. I would suggest taking the head to your local machine shop, especially if you have one that deals with small engines or motorcycles and get them to look at it. If they say its alright get a quality gasket set and run the thing. 350 heads should be a dime a dozen on ebay they made a million of them.

On a SOHC Honda the head and rocker cover are a set.

Not on a 350. The only parts that have to/should stay are the cam bearings and the cam, and that is only due to the fact they have worn in together. Those engines were designed to have individual parts replaced without having to change out entire major assemblies.