trx125

I just got my heads back from the machine shop. My father in law picked them up for me. The nearest machine shop that specialized in toyota heads is over an hour drive each way. I told them exactly what kind of gaskets I was using and this is what I received back from them. Not only can you see the scratches, you can feel them as well. This is suppose to be a very reputable shop that handles toyota heads for dealerships all around our area. I am going to call them tomorrow to see what needs to be done. My plan was to use Hylomar sealer and a MLS gasket. Oh well, I will get off my soap box now. I am just curious as to everyone's thoughts on this.

trx125

My thoughts exactly. It looks like they dragged behind a car on the road to mill them flat!

danimal92sport

You may be used to seeing a milled finish - this appears to be belt sanded (not joking). This is a known technique that many shops use to level the surface, but isn't exactly...exact. Most shops use 40 - 100 grit silicon carbide belts to do this, which would lead to a finish like what is shown.

I'm not stating that this is either a good or bad method, as I'm no head surfacing expert. Just guessing at the technique.

-Dan

KU_MechE

I believe the best machining available for a cylinder head is surface grinding. It looks like that was used here.

sportscarfan

The right thing to do is to call the shop and have a friendly conversation about what they did.
You do not want a mirror finish - the gaskets won't seal, much like piston rings need a crosshatch'd hone finish to seal.
If you have a known precision flat (purpose ground bar, or surface), check it for straightness.

trx125

I called the shop and they said they do a belt sanding on all their heads. I have never used an MLS gasket, but I was under the understanding the head surface had to be below a certain RA. I was plan on using the Hylomar in conjunction with the gasket as is. After talking with the shop in the begining, I made sure they knew I what I was using and the kind of surface it needed. The rest of the work on the head is excellent and the finish would be fine for composite gaskets. The surface is trued and flat now, just really rough.

Potomacduck

That doesn't look like a problem to me.