[eric32]

Hello guys I got a brand new gm zz4 hydraulic roller cam off of ebay and I just got it today and needless to say they threw it into a box and nothing else. I have had cams shipped that way before but they had padded ends on it though. Anyways I tried to take some pictures but I could not get them to come out right.

At the end of the cam nose where it spins on the front bearing to where it starts the stepped nose it has a few scratches on it like indentations and if you rub your finger nail across it you can feel slight rough edge going over the scratches.

I know it can't be like that cause it will toast my cam bearing in the front in no time. My question is is there a safe way to like sand it down to make it smooth to where the scratches wont catch the tip of my finger nail? Looked the cam over and there are no signs of it being dropped or anything. I know the the few scratches there won't hurt anything as long there is no roughness sticking out to cut into my bearing. I would take a file but I don't want to make it worse and don't know where to begin.

Thanks
Eric

[bigdog7373]

I have used an attachment on a dremel that looks like a small soft buffer kind of thing and it takes sharp edges off but doesn't remove barely any metal unless you sit there and hold it in one spot. It works good for cam bearings but i wouldn't recommend it for any major bearings. I wouldn't ever buy a cam off ebay though. How much did you pay for it? You could've gotten a basic jegs or summit brand cam and lifters for 89 bucks. They're actually not bad, i have one in my 350.

[kyle86]

I've used 1000 grit followed by 1500 sand paper before to take surface rust off the journels. Worked good for me, might work for you.

[ericnova72]

Use a flat hone stone, like a small hand held for knife sharpening if you can't find one any other way. Stone is what we use in tool & die when something gets nicked. Get it to the point where nothing sticks up above the surface and it will be fine, don't worry about an indentation.

[eric32]

Well the cam was brand new and there feedback was 99.8 percent. Anyways it's a zz4 hydraulic roller cam which goes for $230 new and I got mine which is brand new and never runned and it only cost me $150 shipped. Anyways not saying anything bad to anyone so please don't anyone take it that way.

Also I don't have a dremel tool so I will try the sand paper first then a stone. The stone would probably be the quickest to start off with. Also if I use the stone how do i go about without causing more scratches or damage the cam?
Thanks guys
Eric

[cobalt327]

Originally Posted by eric32

Well the cam was brand new and there feedback was 99.8 percent. Anyways it's a zz4 hydraulic roller cam which goes for $230 new and I got mine which is brand new and never runned and it only cost me $150 shipped. Anyways not saying anything bad to anyone so please don't anyone take it that way.

Also I don't have a dremel tool so I will try the sand paper first then a stone. The stone would probably be the quickest to start off with. Also if I use the stone how do i go about without causing more scratches or damage the cam?
Thanks guys
Eric

Whatever you do, do not use a hardware store blue knife sharpening stone. That's WAY too coarse for the work you're doing.

There are stones made for the purpose. They are VERY fine grained, soft, and take some work to remove any significant amount of metal.

Shown are two stones I use for what you're contemplating. You cannot feel any coarseness w/your fingers (well, w/mine anyway).



I have (somewhere) a set of white stones that are in various shapes- wedge, cylinders, etc.- that are also good.

The Dremel tools for this deal would be something like the rubberized abrasives points Cratex makes.

[ericnova72]

Cobalt has a point, not the blue knife stones, I was thinking the white or fine gray.

If you use fine sandpaper, wrap it around something like a metal block to provide support so you can control the point of contact.

[eric32]

Hello cobalt if I go to my local hardware store or auto part store or maybe Napa what kind of a stone would I ask for and I am sure I should tell them it's for tools correct? Sorry I sound kind of dumb here but I am new to so many things I am learning a lot of stuff here.

I am not a tool expert but would like to learn though. Anyways thanks for the photos. The one with the handle would be the one I would want to get cause of the angled ends and such. I will pick up some 1000 grit sand paper as well.
Eric

[SSedan64]

If there's a Machine tool or supply house that sells machine shop tools close to you ask for a fine Deburring stone.

[cobalt327]

I missed your question, sorry.

You can also try dressing sticks and honing stones.

GRANGER has a large selection under "stone", might see something there that's applicable.

After you dress the high spots as best as you can, you might want to do the "polish w/fine paper and a shoestring" deal like we've discussed here before for removing surface rust from round journals.

If you have a good magic marker, you could use it as a type of machinists blue to show high spots, after a "shoe buff" motion over the affected area w/the fine paper.

Good luck.

[eric32]

Hello guys thanks for your advice. I would show you guys a picture but the cam is to shiny and the camera keeps doing the flash thing. Any ways I live in a very small town and its hard to get stuff like this around here. I can go to my napa store and see what they have and to start off with if I use some 1000 grit paper do I just sand over the scratched area as lightly as possible and just a little here and there? I don't want to ruin the surface of this thing. Kyle86 can you give me some advice on how you sanded your cam. There are a few spots of rust i need to take off of a few lobes how do I safely do this? Thanks guys for your help.
Eric