DNJ Gaskets - has anyone used DNJ gaskets?
('98-'00)
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Head Gaskets
I had measured for warp every which way w/ a machinists 24" straight edge, accurate to .0001". There was no more than .00125", well within specs for maximum allowable warp, so that was not the issue. Followed all recommended torque procedures and patterns.
Then I bought a set of "6 star" and followed to the letter the recommended guidelines. They recommend a surface finish of 50 RA or less. This is what is referred to as "Roughness Average", measured in microns using an optical comparitor found in any good machine shop. My machine shop put my heads on their lapping machine and in short order had them to about 10 - 12 RA. They had a mirror finish when I got them back, $75 for both. I didn't want to break-down the block and bring that in even though the engine was on the engine stand. What I did was to get a scrap piece of polished, 1" thick granite building cladding, granite counter top will do also (this stuff is FLAT!) and cut it with a masonry blade to 6" x 10" slightly beveling the edges with a diamond coated file to remove the sharp edge.
I used a VERY light coating of 3M 77 spray adhesive to bond 400 grit wet / dry auto body paper to the stone, working my way down to 1500 grit, just using water as my lube and flushing medium. Pack the cylinders and all other openings with oil dampened rags before you start. Yes, it was tedious and took hours, but when I was through the block surfaces looked every bit as good as the heads. Work all areas evenly as you go. Cleaned all thoroughly and reassembled.
That was in 2005. I haven't had one lick of problems since, and it's been 14 years now!
Good luck.
All I know is I went through two sets of head gaskets within 1 year for my '98 Fos w/ the 2.5 DOHC engine, then I did my homework! The first set were "FelBlow" and the second were Subie branded from the dealership parts dept.
I had measured for warp every which way w/ a machinists 24" straight edge, accurate to .0001". There was no more than .00125", well within specs for maximum allowable warp, so that was not the issue. Followed all recommended torque procedures and patterns.
Then I bought a set of "6 star" and followed to the letter the recommended guidelines. They recommend a surface finish of 50 RA or less. This is what is referred to as "Roughness Average", measured in microns using an optical comparitor found in any good machine shop. My machine shop put my heads on their lapping machine and in short order had them to about 10 - 12 RA. They had a mirror finish when I got them back, $75 for both. I didn't want to break-down the block and bring that in even though the engine was on the engine stand. What I did was to get a scrap piece of polished, 1" thick granite building cladding, granite counter top will do also (this stuff is FLAT!) and cut it with a masonry blade to 6" x 10" slightly beveling the edges with a diamond coated file to remove the sharp edge.
I used a VERY light coating of 3M 77 spray adhesive to bond 400 grit wet / dry auto body paper to the stone, working my way down to 1500 grit, just using water as my lube and flushing medium. Pack the cylinders and all other openings with oil dampened rags before you start. Yes, it was tedious and took hours, but when I was through the block surfaces looked every bit as good as the heads. Work all areas evenly as you go. Cleaned all thoroughly and reassembled.
That was in 2005. I haven't had one lick of problems since, and it's been 14 years now!
Good luck.
I only use FelPro. I have done over a dozen cars using the FelPro kit and they all are still on the road. Longest was over 120k miles until the guy drove it off a cliff. I have heard nothing but good things about the six star, however I have never used them myself. I have used the FelPro gaskets on N/A foresters all the way up to 800plus horse Rexes. If done correctly, the pistons and rods will let go before the gaskets.
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