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EA82 getting head surfaces clean


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Doing the head gaskets and wondering what I should use to scrape the old material off and get the surfaces prepped for reassembly.  I was using a razor blade to start with but am worried about gouging the surface.  Switched to a 3M scotch Bright pad and its not getting me very far.  Any Ideas?

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Managed to get them all cleaned off with the scrub pad and a few more beers. Should I really resurface the head?  The motor has just over 100k on it and there was just a light seep in the rear bottom corner of the passenger side head.  Otherwise, I have not had any issues(knock on wood/cross fingers/sacrifice goat).  If it seeps a little I can live with it. I decided to do the job and had it apart before i read that these motors like to mark their territory a little, probably would not have done it in hindsight.  Dont really have the time and resources to do what grossgary is suggesting though I like the setup!

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you absolutely want as perfect a finish on the heads surface as you can get.  It doesnt even cost much at a machine shop, and little or nothing if you do it yourself with the glass method.  skip that step and you will just have them back out again and again until you do it right.

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best to do it. they always have high and low spots and are not flat so it's basically risky to hope they're not "high or low" enough to cause an issue.  look at the high spots in the pictures in that thread and how long it takes - some areas remaining untouched, your heads are like that.

 

I guess you could try to measure the high and low spots and check against FSM clearances but that is a most tedious process and i've never done it.  it's too easy to just sand the things as that link shows...takes a couple minutes and done.

 

time and resources?  you pulled the valve train and heads off a motor, it takes a fraction of that effort and resources to get a piece of glass and sandpaper.

 

if you want the gaskets to last 20,000 miles and a year or two then maybe who cares - instead of wanting it to last a long time.

 

all that being said - i've skipped resurfacing older generation heads before...but it's a really bad idea.

 

use Fel Pro permatorque gaskets, i wouldn't use any old cheap ebay classics out there.  and Subaru requires the headbolts to be retorqued where the Fel Pro's do not require that step.  completely pointless to replace the headbolts on Subaru's in case you didn't know.

 

use a Subaru intake manifold gasket, the aftermarkets are flimsy and failure prone.

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The sandpaper is standard wet dry paper in an 8.5x11 or so sheet.  I personally am using a piece of Granite that I tripple checked with my Snap-On straight edge.  Its as perfect as it gets and I like that its thicker and heavier than a piece of glass so I didn't have to mount it to anything.  I just put it on an old beach towel folded in a couple halves and onto the bench it goes when I need it.  The grey WD40 and aluminum mixture is pretty messy as is the adhesive.  Be very careful with the adhesive its extremely flammable.  Probably the most dangerous thing in my shop and that says a lot.  Vent after using!  

 

I only use this on ea series engines at my shop.  For anything EJ I send them out.  The size of the head vs the paper makes it pretty frustrating to keep from tearing the sandpaper.  My customers with the EJ series engines are also typically in a bigger hurry for their car back as well as willing to spend the money on it.  Every customer knows which method I am using and why.  As GD says in his writeup you can often do a set of heads faster than driving back and forth to the machine shop.  In my case its damn close-my machinist is about 4 minutes away but I have to drop off and pick them up.  Usually I have my head surfaces prepped and cleaned by the time they are calling me to let me know they are done. 

 

I have also been cutting with 80 first on any head where the head gasket ring has stamped into the metal all the way around.  Just too deep for 120 or above it takes way too long.  I go from 80 to 120 to 220 usually and the surface is absolutely perfect after this process.  Quite often its as pretty as doing them on a Bridgeport at the machine shop.  

 

For the original question:  I use a 3m Roloc Bristle Disc on a surfacing/right angle die grinder with fairly low speed.  These are rubber discs that aren't as harsh as a Scotchbrite and were recommended by Subaru of America via a service bulletin to replace those as guys were taking metal off with the Scotchbrite.   

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I actually have a set of EA82 Permatorque headgaskets - you want them, i'll give you a few bucks under whatever they cost.  PM or email me at my username here at yahoo.com.

 

I have a granite slab as well but was told by machinists/online forums for machinists that they're not always flat...it depends on the source, how they were cut and manufactured and I don't have the equipment to verify flatness so i went with glass.  When I was looking into it, glass is flat by property/processing.  The granite is awkward due to it's weight too.

 

I use the 3M roloc discs as well that Shawn mentioned.

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Felpro 9392 PT - Ebay or RockAuto.

I also use the glass for resurfacing the heads.  I called a glass shop and asked what they had for scrap.  Found a 1/2" piece 16" x 20".

I use spray contact cement... works great.   And I lay 2 pieces of sand paper side by side so my sanding surface is approx 11 x 16.

Doesn't hurt to resurface the intake and exhaust if you have time.  At least clean them up with the flat glass/sandpaper.

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Ordered the Felpro's from rock auto and sent the other ones back.  Swung by the 2nd hand building supply store and picked up some glass and a square of plywood.  Had some leftover 300g wet-sand paper and followed the directions in the post from grossgary.  The first on turned out great!  Wasnt bad to begin with but crazy how you can def see the high and low spots once you get started.  Doing the next one tomorrow, thanks everybody!

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