Ive got the worse luck with this 2000 Civic EX. After pulling the engine twice and getting the machine shop to correctly bore the block for the pistons, put everything together and everything ran great. Sold the car to a neighbor only for neighbor to come back to me explaining getting misfire codes and coolant loss. Leakdown tests show 1,2, and 3 cyl leaking fair amount and valve cover has yellow sludge. All this with less than thousand miles on the new build. I pulled the head and dropped it back off to machine shop to get cleaned up, tested, and ready for reuse. The owner told me that the cheap chinese DNJ head gaskets (3 layer MLS gaskets) are just as good as Honda/Cometac. Is this correct and if so why the cost difference? He supplied me the DNJ gasket set free of charge the 2nd time I had to get the block sent back to him. I normally refer genuine Honda based on comments.

Can cheap head gaskets blow across cylinders that easily in a non turbo stock setup? Engine is a D16y8

I measured the block flatness and i could not get .0015 feeler gauge under any part of the block and machinist ruler. I ran over it with 3000 grit sand paper just to clean up the surface and remeasured for flatness. Its really smooth now. Will this suffice for a new Honda MLS gasket? Machinist stated Honda needed about 6 - 8 on the RA scale which is as smooth as glass. Is this correct?

 

Machinist said head was still flat and passed pressure test. He advised the use of a Honda OEM gasket which I already ordered along with new head bolts.

So back to my original question for any of you gents. Is there such a thing as too smooth for a MLS Nippon head gasket such as the Honda OEM?

 

No. Also the viton coating of the MLS gasket will fill tiny imprefections in the mating surface anyway. The coating replaces old copper spray.

I've had really good luck with Fel-pro Permatorque head gaskets. They have a blue viton coating over Honda's black viton coating. Both should work just fine.

I would suggest either getting your torque wrench calibrated or buy a brand new one with certificate to do the head bolts in sequence. I would suspect that first being you are not getting good results and everything checks out flat.

Oh if you do buy a new one, you should click it a few times on your lug nuts at say 70 ft-lbs first. Sort of a break in process. After clicking it a few times at a decent torque setting it should be good to go on the head bolts.

 

Good point about the torque wrench. Its a Harbor Freight wrench. Im gonna take it up to friends shop and do some testing and compare it with his electronic SnapOn wrenches to see if its within spec.