Subarutex Posted November 16, 2004 Author Share Posted November 16, 2004 Tonight we pulled the engine and tore it down. Massive HG failure on the drivers side, both cylinders were like this one: So... what do you think cause that? Just the 10psi of boost? I believe copper head gaskets are needed, your thoughts? Improper torque of headbolts? Maybe I need studs... Slight surface rust, after only 4 days! What should I do? Are my brand new rings hosed? Quote Link to comment Share on other sites More sharing options...
idosubaru Posted November 16, 2004 Share Posted November 16, 2004 i had the same thing happen to my XT6. installed new headgaskets. motor out of car, cleaned up everything, cleaned bolt holes, cleaned head bolt threads.....30,000 miles later my pass side HG leaked and looked EXACTLY the same as yours when i pulled it. now my drivers side is doing the same thing as the pass side did....i'm pulling it in the next couple days and i can promise it'll look the same, failure in the same exact spot. the same relative cylinder....front of motor has the leak. i read through a good bit of material trying to figure this out and i did read in two places that ignition problems can cause premature head gasket failure. one site even claimed "poor ignition timing is the leading cause of head gasket damage"....? i'd guess overheating, but whatever that's not the point. i had mad ignition timing problems with mine and kept driving it like that for a long time. maybe that caused it, maybe not. i still never addressed that timing issue, so who knows. i was never able to get the distributor lined up properly....long story with no end yet. anyway, i should go address that distributor. have you had any timing issues? Quote Link to comment Share on other sites More sharing options...
idosubaru Posted November 16, 2004 Share Posted November 16, 2004 those head gaskets should hold 10 psi just fine. you could try corteco gaskets, roughly the same price and i've heard good things about them. i'm installing them on my XT6. Quote Link to comment Share on other sites More sharing options...
subaru_styles Posted November 16, 2004 Share Posted November 16, 2004 hey tex..at least you didn't do this on run with a fresh motor.. Quote Link to comment Share on other sites More sharing options...
Turbone Posted November 16, 2004 Share Posted November 16, 2004 I think what Gary is trying to say about the timing issue, is the dreaded "pre detonation". This just might be your problem Tex. Quote Link to comment Share on other sites More sharing options...
WJM Posted November 16, 2004 Share Posted November 16, 2004 That makes me wonder is the block was not true...the rings should be fine. Head were true, correct? with the ignition timing...my 9.5:1 turbo engine knocked, pinged, pre detonated every day of its life. It lasted 24k miles on OE head gaskets. The rings and an exhaust valve let go before the HGs. The heads were known true, and the block was pulled out of a wrecked car, about 80k miles on it and was a well maintaned block...so it was true. Quote Link to comment Share on other sites More sharing options...
Subarutex Posted November 16, 2004 Author Share Posted November 16, 2004 Heads were true... Pretty sure it was the detenation that did it. Quote Link to comment Share on other sites More sharing options...
WJM Posted November 16, 2004 Share Posted November 16, 2004 Strange that my 9.5:1T didnt blow HGs... Quote Link to comment Share on other sites More sharing options...
oddcomp Posted November 16, 2004 Share Posted November 16, 2004 detonation will kill anything if left uncorrected anywhere from breaking heads to hammering that prized crankshaft out of the oilpan. not really a exageration it has happened but i be the motor sounded like a rock crusher before it happened Quote Link to comment Share on other sites More sharing options...
Subarutex Posted November 16, 2004 Author Share Posted November 16, 2004 The car ran for about 80 miles with the drivers side cam off one tooth. Disty timing was set to 23 degrees off of cylinder 1. Now, while I never heard detanation during this period, its probable that damage was still done then. Hopefully the machine shop can check the block for trueness and true it without splitting the block. I will also have the heads true'd again, or atleast checked. Quote Link to comment Share on other sites More sharing options...
subaru_styles Posted November 16, 2004 Share Posted November 16, 2004 c'mon tex...say it with me....... E......J......... Quote Link to comment Share on other sites More sharing options...
WJM Posted November 16, 2004 Share Posted November 16, 2004 E.......A........Eighty.......Two....TURBO! Quote Link to comment Share on other sites More sharing options...
baccaruda Posted November 17, 2004 Share Posted November 17, 2004 did your gas mileage reflect anything funny recently? The car ran for about 80 miles with the drivers side cam off one tooth. Disty timing was set to 23 degrees off of cylinder 1. Now, while I never heard detanation during this period, its probable that damage was still done then. Hopefully the machine shop can check the block for trueness and true it without splitting the block. I will also have the heads true'd again, or atleast checked. Quote Link to comment Share on other sites More sharing options...
Subarutex Posted November 17, 2004 Author Share Posted November 17, 2004 Yes, in those 80 miles i used about a half tank of gas. Quote Link to comment Share on other sites More sharing options...
idosubaru Posted November 17, 2004 Share Posted November 17, 2004 my passengers side head gasket lasted 30,000 miles through my ignition problems. the current drivers side has 37,000 miles on it and it's leaking about a gallon every 100 miles internally. it's getting replaced this weekend. they still lasted awhile. but i drive over 30,000 miles a year, i don't want to be changing head gaskets once a year....grrrrr..... lots of variables involved....i just know in my situation there are too many coincidental things going on more than once for it not to be something wrong. i'm HOPING it's ignition related so i can keep this from happening again. Quote Link to comment Share on other sites More sharing options...
Subarutex Posted November 17, 2004 Author Share Posted November 17, 2004 After having a long talk with the copper gasket guy, I'm pretty sure this blow out is a result of not having enough clamping force on the ring around the cylinder. Whether this was caused by not retorqueing the head bolts, using used stretch bolts, or simply not torqueing to the high side of the stock range. I'm going to give copper head gaskets a try. Haven't decided if i'm going to have the steel ring around the cylinder or not. WILL probally use sealant. May or may not use studs... Quote Link to comment Share on other sites More sharing options...
oddcomp Posted November 18, 2004 Share Posted November 18, 2004 if i was you i would go for studs if you can afford it .. lot less chance of having to go back in and redo it plus you can safely get that high clamping you need with less fear of stripping the block and its so cool to say hey look oohh i got studs nya nya Quote Link to comment Share on other sites More sharing options...
NorthWet Posted November 18, 2004 Share Posted November 18, 2004 I've always been a big fan of using studs, but I thought something the other day that I haven't seen addressed: In this day of torque-to-permanent-stretch (forgot tech term :-\ ) head bolts, how do studs fit into this? Are studs doomed to allow more failures then no-longer-resilient bolts? Just compensate with more clamping force? Any thoughts? Quote Link to comment Share on other sites More sharing options...
garner Posted November 18, 2004 Share Posted November 18, 2004 Tex, Keep us in the loop on the prices etc of copper hgs and head studs. If it was possible to set up a group buy deal I very well might be interested and bet other EA82T nerds would be as well....Might save us all some dough compared to going it alone... garner Quote Link to comment Share on other sites More sharing options...
Dr. RX Posted November 18, 2004 Share Posted November 18, 2004 You have to understand why studs are better then bolts. When bolts stretch, they get longer, and by getting longer, they will bottom out. When they bottom out, they will show the correct torque value, but they will not be applying the clamping force needed where it counts. Studs stretch too, but they stretch away from the head, so it is the nut and washer that is applying the clamping force, and as long as there are threads below the surface of the hole where to stud come through, the nut will apply the correct force. Now, the next thing, are there studs available for the Subaru EA82 series engines? Another thing to consider, once you have installed studs, it will mean that you will have to pull the engine if you ever need to replace a head. Quote Link to comment Share on other sites More sharing options...
Subarutex Posted November 18, 2004 Author Share Posted November 18, 2004 Corky, the PREracing guy said he had head studs, he said he got them from ARP. I tried calling today, but ended up leaving a message. The number is on the website www.preracing.com if you'd like to spare your tremendous amount of free time and help me out Quote Link to comment Share on other sites More sharing options...
NorthWet Posted November 18, 2004 Share Posted November 18, 2004 You have to understand why studs are better then bolts. When bolts stretch, they get longer, and by getting longer, they will bottom out. When they bottom out, they will show the correct torque value, but they will not be applying the clamping force needed where it counts. I do not believe that this is correct. The majority of bolt holes have sufficient depth to prevent bottoming. What the "new" bolts do is get torqued past the limit of elasticity, permanently deforming (which is why they are supposed to be used once and then replaced). This eliminates the "give" of a bolt, the steel's inherent springiness, that would allow inconsistant holding force. Quote Link to comment Share on other sites More sharing options...
carfreak85 Posted November 18, 2004 Share Posted November 18, 2004 In this day of torque-to-permanent-stretch (forgot tech term :-\ )QUOTE] The term you're looking for is "torque-to-yield". Quote Link to comment Share on other sites More sharing options...
NorthWet Posted November 18, 2004 Share Posted November 18, 2004 The term you're looking for is "torque-to-yield". Gratzi!!! Quote Link to comment Share on other sites More sharing options...
Dr. RX Posted November 18, 2004 Share Posted November 18, 2004 I do not believe that this is correct. The majority of bolt holes have sufficient depth to prevent bottoming. Sorry to differ with you, but I'm talking from experience here. In the beginning, when everything is new, yes, I'd agree that there is plenty of room at the bottom of the hole, but I'll bet it is less then a 1/4 of an inch, and the bolts can easily stretch that far and more over a period of time. Quote Link to comment Share on other sites More sharing options...
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