idosubaru Posted April 1, 2011 Share Posted April 1, 2011 (edited) The EJ25 heads I had resurfaced and pressure tested are rougher than any set of heads I've ever gotten. Same place I've always gone since moving here, they do the local dealership machine shop work too. There are visual gouges. The worst one traverses all the way from the combustion chamber to the edge of the head. It gets shallower as it goes and is much shallower by the time it reaches the gasket. Also, wiping white shop towels across it pulls tiny fluff off the towel. I'm used to a smoother surface than this. I realize machining is mostly for flatness but what say y'all? Does this sound normal? *Edit I attached the best cropped photo I have of the gouge I mentioned above. It shows a bit of what I'm talking about. The worst gouge is about 1/2" to the left of the hole on the right in the picture. Edited April 1, 2011 by grossgary Quote Link to comment Share on other sites More sharing options...
Olnick Posted April 1, 2011 Share Posted April 1, 2011 I know nothing about machining and resurfacing but Wow! That looks terrible, even to my untrained eye. Quote Link to comment Share on other sites More sharing options...
naru Posted April 1, 2011 Share Posted April 1, 2011 Looks too rough to me.I`d be worried. Quote Link to comment Share on other sites More sharing options...
davebugs Posted April 1, 2011 Share Posted April 1, 2011 Not lookin' good Gary. Actually I can't believe they let them go out the door like that. If they are too bad to repair PM me. I have a set on an engine that had been overheated many times - but I'll make you a heck of a deal. The intake is off but the heads are still on it. Quote Link to comment Share on other sites More sharing options...
Fuzpile Posted April 1, 2011 Share Posted April 1, 2011 I thought most resurfacing was really milling with a vertical facing head. Like a large flycutter, it leaves faint arcs for it's part of a circle. It does require a very precision setup and sharp tooling. The pic'd head appears to have been done with a file and one too rough. You can see the lines/faint scratches are all in a line with the gouge. ther also appears to be faint camfering at the edge of the comb chamber which again could happen by bearing on a file. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted April 1, 2011 Author Share Posted April 1, 2011 great thanks guys, glad i didn't bother bolting it together. i'll take them to the shop tomorrow and see what they say. Quote Link to comment Share on other sites More sharing options...
walczyk Posted April 1, 2011 Share Posted April 1, 2011 Wow yeah, that looks worse than if you didn't resurface at all. It looks like someone messed up real bad and didn't notice or didn't want to take the blame. They might be ruined if the gouges are very deep. The grinding limit for the head surface is 0.012" and the warping limit is 0.002". I am reading this out of the service manual for a 2000 legacy GT (its an EJ252 I think, I still have no idea what the differences between the 251 are). The standard height of the head is 3.839", so if you end up measuring anything less than 3.827" after grinding then subaru recommends you scrap the head. Its a judgment call, but you better raise hell at the place that did that abortion of a resurfacing job. Quote Link to comment Share on other sites More sharing options...
Fuzpile Posted April 1, 2011 Share Posted April 1, 2011 There's some wet "grinding" op I wouldn't know about for alum heads. Grinding is typical for iron but aluminum tends to clog and burn into the abrasive causing hot-spots and bad things. What is similar is a rough file which has picked up a piece of alum andor hard carbon and this has embedded into some teeth. Drawn across the softer head, it can gouge.. Quote Link to comment Share on other sites More sharing options...
Crazyeights Posted April 2, 2011 Share Posted April 2, 2011 It looks like that was done on a belt. All the ones I have ever gotten back you can see a semicircular pattern from the cutting tool. I'd be concerned. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted April 2, 2011 Author Share Posted April 2, 2011 thanks for all the feedback, this has been helpful and informative! if the heads are beyond limits then what? i'm not one to demand things in situations like this but if they ruined good heads that's tough. guess i just wait and see what they say. hopefully they mic fine or are good to work with. i don't have a mic to check myself. Dave - maybe you could PM a price on your engine/heads so i can give them a "quote" just in case they offer? they have a belt though i was never sure what they used it for. i didn't know until this thread how heads were resurfaced or that there were multiple ways to do it. i figured it was a fairly standard operation. i have a head that they did for me last year on the shelf that looks normal, so i'll take that one with me. it is warrantied so maybe they require it be installed and have them fail first for the warranty to kick in? Quote Link to comment Share on other sites More sharing options...
subaru360 Posted April 2, 2011 Share Posted April 2, 2011 April fools joke I hope. The pic looks like somebody took a belt sander to it. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted April 2, 2011 Author Share Posted April 2, 2011 April fools joke I hope. The pic looks like somebody took a belt sander to it. no, not quite but nice thinking. i wish it was, this seems like it's going to be a PITA. Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted April 2, 2011 Share Posted April 2, 2011 The pic looks like somebody took a belt sander to it. That's exactly what I was thinking. They just set it on a belt sander and let it rip. No way I'd put that on a car. Quote Link to comment Share on other sites More sharing options...
Fuzpile Posted April 2, 2011 Share Posted April 2, 2011 Yeh. You guys are right. It never occurred to me someone would use a belt sander. That explains a lot. A good mill file or drawfiling would have corrected a lot. Getting below that gouge would require actual milling, then it may be below the specs. It's not Just thickness which can be adjusted by a thicker headgasket. The coolant passages on some heads are actually wider inside the head compared to the surface. So if milled too far- that's where it will Blow. Good luck. Quote Link to comment Share on other sites More sharing options...
ShawnW Posted April 2, 2011 Share Posted April 2, 2011 http://www.aa1car.com/library/ar996.htm Article above describes the methods and how smooth, etc it should be. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted April 2, 2011 Author Share Posted April 2, 2011 what would you do given the end result below? right now i'm out two headgaskets that i bolted on before thinking better of it and getting your feedback. and i now have two heads below spec too. he said they always use a belt. he wasn't bothered or offered any comment on the gouging or the heads being out of spec (numbers below). he touched up the really bad one i posted the picture of. he mic'ed the heads at 3.82" and 3.81" which is right at or just below the Subaru minimum, if the 3.827" mentioned in an earlier reply is correct. the lowest one was the one he didn't touch up as that one didn't look nearly as bad...and was obviously low and shouldn't be shaved any more. the limits are probably conservative? i'm using the thicker Subaru headgaskets which are 37 thousandths (0.037) thicker than the normal headgaskets (1.52 millimeter instead of .58 mm). maybe that buys me enough additional space? this is for SOHC EJ25 heads on a DOHC block swap. Phase II heads on a Phase I block. There is interference when using the thinner gasket, the pistons hit the head so there's not a lot of room to work with. Is there any way to calculate how much? Quote Link to comment Share on other sites More sharing options...
davebugs Posted April 2, 2011 Share Posted April 2, 2011 Gary, How do they look now? Regardless I probably wouldn't use them. You're doing something "non-standard" here anyways. If anything fails you'll always be haunted by this. Any reason you just don't use DHOC heads and be done with it? And I'd definatley find another shop. Quote Link to comment Share on other sites More sharing options...
curtisbad Posted April 2, 2011 Share Posted April 2, 2011 i'm a machinist and resurfaced my heads when i did my head gaskets. they looked nothing like yours. what did they use , a chainsaw??? umm , i'm seriously thinking that those are junk!! i'd certainly complain and demand my money back. that work is unacceptable. there's no way that a gasket can seal all of those gouges, deep scratches and butchery. man, i hate that for you. i can't believe that the shop you took them to allowed them to leave their shop in that shoddy condition. TERRIBLE!!!! curtis Quote Link to comment Share on other sites More sharing options...
idosubaru Posted April 2, 2011 Author Share Posted April 2, 2011 How do they look now? much better than before. it was only the one that was really bad. Any reason you just don't use DHOC heads and be done with it?as you know, can't plug and play a DOHC Phase I into a SOHC Phase II vehicle. there's not one automotive machine shop where i work, which is the third largest city in the entire state. welcome to a small state. i'm hosed when it comes to machine shops, it's the only one i know of even close to here. all the machine shops around here work on mining equipment, because i called them all a couple years ago. Quote Link to comment Share on other sites More sharing options...
curtisbad Posted April 2, 2011 Share Posted April 2, 2011 much better than before. it was only the one that was really bad. as you know, can't plug and play a DOHC Phase I into a SOHC Phase II vehicle. there's not one automotive machine shop where i work, which is the third largest city in the entire state. welcome to a small state. i'm hosed when it comes to machine shops, it's the only one i know of even close to here. all the machine shops around here work on mining equipment, because i called them all a couple years ago. befriend a machinist. you'd be amazed how many "side jobs" i've done over the years for friends and family. redoing some heads doesn't take long. ten minutes maybe. that's about how long it took me to do them on a large milling machine. maybe a little longer if you figure in set up time. you don't necessarily need an automotive machine shop to do them. any machinist with some knowledge can do them for you. curtis Quote Link to comment Share on other sites More sharing options...
idosubaru Posted April 2, 2011 Author Share Posted April 2, 2011 what's your address and how much do you charge. good call, wonder if i can pull that off somehow? i'm not really in a good place for that, my friend that works for the mercedes dealer and the subaru dealer both use that shop. i'll make some calls next week, thanks. Quote Link to comment Share on other sites More sharing options...
davebugs Posted April 2, 2011 Share Posted April 2, 2011 Gary, I usually pay around 120 for resurface, check for cracks, steam bath. To get valve seals and such done not much more (for labor) but my guys tell me Subaru's very rarely need them. Quote Link to comment Share on other sites More sharing options...
curtisbad Posted April 3, 2011 Share Posted April 3, 2011 for diy , you can clean the heads with diesel fuel and water. heck , you could just get a can of any parts cleaner. you can also buy a three part crack checking kit for like 20 or 30 bucks at a parts store. it's really easy to do. now the valves on the other hand aren't so diy friendly. i don't know what happens with other SUBARU's but my valves were fine. it's also a good idea to check the cam(s). a machine shop can grind them if need be and can take bend out of them if required. wish i were closer, i'd gladly help you out. i'd even do the machine work for free if you asked nicely. curtis Quote Link to comment Share on other sites More sharing options...
GeneralDisorder Posted April 3, 2011 Share Posted April 3, 2011 Gary - here's what I know. Hope it helps. There are multiple methods used for "surfacing" of cylinder heads: 1. I have seen shops use belt sanders..... personally I dislike the method. Both because of surface finish as well as the implications for the surface not being "square" to the casting. That is taking off more material from one side than the other. *probably* not an issue in practice but it bothers me. I won't take my heads to shops that do this. 2. Blanchard ground.... this is what most *good* machine shops use. It's also used for surfacing flywheels. This is what produces the characteristic swirl pattern that most are familair with. 3. It is possible to either do it on a milling machine with the right setup (fly-cutter, or even an end-cut mill) or even by chucking them into a large enough lathe..... but these are not common methods. I have resurfaced heads myself using progressively finer sandpaper (usually stopping at 240 grit) and WD-40 on a thick pane of glass backed up by quality plywood with a finished side. This works very well but is time consuming and takes some skill. Since they are likely true due to the belt-sanding.... I would just clean then up with some 120 grit and glass. If this was an older 2.2 I would say throw them on as the composite head gaskets will suck up that rough finish. As it is with the MLM gaskets of the EJ251 I would want a better finish than that. The machine shop is obviously a bunch of hacks. Don't go there anymore. GD Quote Link to comment Share on other sites More sharing options...
idosubaru Posted April 3, 2011 Author Share Posted April 3, 2011 Since they are likely true due to the belt-sanding.... I would just clean then up with some 120 grit and glass. you wouldnt' be worried about the one thousandth or less below subaru's stated minimum i mentioned above? thanks all. Quote Link to comment Share on other sites More sharing options...
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