Subaru Green Posted March 20, 2017 Share Posted March 20, 2017 I'm in the process of a 2.5 rebuild for my 2000 Legacy GT. I've read more than enough to be convinced that new headbolts are unnecessary, so I've completely cleaned and brass wire brushed the original bolts and have two questions: 1. Most of the bolts have a slight indent in the center of the head with an "S" stamped in the dip. There are other bolts that have a round circle at the center of the head, but it does not make an indent. Is this a problem? Do the bolts differ in location? I'm guessing it means nothing but I hate making mistakes based on assumptions and guesses. 2. Since I'm reusing the bolts, do I follow the 8 step pattern of torque and degree adjustment? Or do I skip the steps that "stretch" the bolts - which seem like steps 2 to 4. Any guidance would be greatly appreciated! Link to comment Share on other sites More sharing options...
matt167 Posted March 20, 2017 Share Posted March 20, 2017 If you have wire brushed the bolts, then get new ones. It can change the torque values and that COULD be a mistake. Use the full process from the manual regardless. They are not TTY bolts and that's why you can reuse them if still in good condition.. Factory manual should also tell you where the bolts go if they are different and you lost track Link to comment Share on other sites More sharing options...
Naked Buell Posted March 20, 2017 Share Posted March 20, 2017 I would have to agree. I thought wire wheel would be ok until more than two people, and now this previous post has confirmed that you don't want to do that, and that is coming from professioinal builders, i.e. General Disorder. Besides, bolts aren't that much money for insurance. There is a lot of pressure on those heads. It is containing explosion after explosion. Trust them, new bolts. Link to comment Share on other sites More sharing options...
Subaru Green Posted March 20, 2017 Author Share Posted March 20, 2017 Well, not surprised and many thanks. I'm trying to learn as much as possible and get it right at the same time, hence the "Green" in my name. I'll definitely just get the new bolts and sleep much better. Thanks so much! Link to comment Share on other sites More sharing options...
AdventureSubaru Posted March 20, 2017 Share Posted March 20, 2017 Bummer. I scrapped about 3 sets of used ones before we moved cross country last fall. I'd have sent them to you for the cost of shipping. Maybe put a want ad in the classifieds here. Someone may have some leftover as I did. Link to comment Share on other sites More sharing options...
GeneralDisorder Posted March 20, 2017 Share Posted March 20, 2017 (edited) They aren't expensive from the dealer. Use Amsoil engine assembly lube liberally on the bolt threads and between the bolt head and washer. Use nothing between washer and cylinder head. The bolts are (what appears to be) aluminized and this is an additional anti-friction coating. It helps avoid the creaking. If you clean the bolts, and block threads correctly and use the Amsoil assembly lube you will have zero creaking. If you do it the service manual way and use engine oil you will have nothing but problems. The service manual leaves a LOT to be desired as a build/rebuild guide. It's wrong or incomplete in almost every respect as applies to short block building. That's why dealers don't go that far into them. The success rate with their service department parts hanging monkeys is very low. GD Edited March 20, 2017 by GeneralDisorder 1 Link to comment Share on other sites More sharing options...
Subaru Green Posted March 21, 2017 Author Share Posted March 21, 2017 Can't thank you enough. The relatively low cost of the bolts makes it a no-brainer and I really appreciate the Amsoil info. This triggered my reading about it and it makes total sense. It's so hard to feel confident when you read the manuals, see it in action on youtube videos and then see even more different ideas on discussion boards. I started out with what I thought was a decent sense of confidence and then felt like a lost soul when I researched more. Thanks for setting me straight! Link to comment Share on other sites More sharing options...
abc Posted July 1, 2017 Share Posted July 1, 2017 Hi folks, I am new to the forum and am researching head bolt torque procedure. I am re-using head bolts and I want to know if I need to do the initial 22 then 51 ft.lbs and back off 180 twice. Is that not meant to pre-stretch NEW bolts? Can I not go to 25 and 11 ft.lbs and the 90 deg 90 deg and get the same results of near 90 ft.lbs Link to comment Share on other sites More sharing options...
GeneralDisorder Posted July 1, 2017 Share Posted July 1, 2017 It is not to pre-stretch the bolts. The bolts don't require that. It's probably another creak mitigation procedure. To get the lubricant applied to the bolts down into the threads prior to final torque. There is no reason to skip this step. There are many ways to torque the head bolts. When using ARP studs, the torque procedure is a simple 30, 60, 90 ft/lbs. But they use different lube, different threads, etc. GD Link to comment Share on other sites More sharing options...
abc Posted July 1, 2017 Share Posted July 1, 2017 That's an interesting thought, thanks Link to comment Share on other sites More sharing options...
Gloyale Posted July 1, 2017 Share Posted July 1, 2017 Also for anyone reading, There are 2 different types of bolts for all SOHC 2.5 and Phase II 2.2 engines. Really it's just the size of hte washer fitted to them. the 2 center bolts have larger washers. teh 4 corner bolts have smaller ones, and ussually a painted head either black or orange to distinguish them. If you put the large washer bolts in the corners, the washer edge hits the Cam carrier frame and deflects sideways just a hair....Throwing off torque value slightly. this being said, i've taken apart good running motors which had bolts mixed up but seemed to not be a problem. But there is a correct way and it's painted bolts with small washers in the corners. Link to comment Share on other sites More sharing options...
golucky66 Posted July 1, 2017 Share Posted July 1, 2017 Just to note your post gloyale. On OEM SOHC head bolts. There are bolts with a black head. Those go in the middle, I think it's because the middle two bolts get an extra 45 degrees in the torqueing. And the middle ones are slightly different to handle the extra torque? Link to comment Share on other sites More sharing options...
Gloyale Posted July 2, 2017 Share Posted July 2, 2017 Just to note your post gloyale. On OEM SOHC head bolts. There are bolts with a black head. Those go in the middle, I think it's because the middle two bolts get an extra 45 degrees in the torqueing. And the middle ones are slightly different to handle the extra torque? You got it backwards. I just assembled one last week. At any the center 2 bolts have larger captive washers, the paint distinguishes them from the outer 4 corners, which have smaller washers to clear the Cam case. None of the bolts are different other than washer size. And none of them get an extra 45 degrees. The center ones get an extra 4~5 ft/lbs of pre torquing(21 Ft/lbs vs. 17ft/lbs). this is before the final step 90 deg. then additional 90 deg. for all bolts. Link to comment Share on other sites More sharing options...
golucky66 Posted July 2, 2017 Share Posted July 2, 2017 And none of them get an extra 45 degrees. The center ones get an extra 4~5 ft/lbs of pre torquing(21 Ft/lbs vs. 17ft/lbs). this is before the final step 90 deg. then additional 90 deg. for all bolts. Um. Ok. We'll the service procedure I pull up from alldata says the centre two get an extra 45 degrees at the very end.... Either way. Doubtful they're going to fail either way. Link to comment Share on other sites More sharing options...
GeneralDisorder Posted July 2, 2017 Share Posted July 2, 2017 (edited) Just to clarify - the paint marks differ from year to year. Sometimes the corner bolts are painted (usually black) and sometimes the center bolts are painted (usually pink). There are different torque procedures in different years of the service manuals. Some have the extra center bolt torque at the end, and some have it at the beginning. Depends on which FSM you are looking at. GD Edited July 2, 2017 by GeneralDisorder Link to comment Share on other sites More sharing options...
idosubaru Posted July 2, 2017 Share Posted July 2, 2017 As far as lubricating the head bolts - what about the lube pushing out of the threads and then getting between the gasket and block? Or is that why lube is better than oil ?That's why I've always disliked oil there. But I'm sure people do it all the time. Link to comment Share on other sites More sharing options...
GeneralDisorder Posted July 2, 2017 Share Posted July 2, 2017 (edited) Lube doesn't typically get on the gasket surfaces because the threads don't start till about 2" down into the block holes. It's never been an issue for us. Lube is required. The bolts cannot be installed dry - the torque procedure will not yield accurate gasket crush. GD Edited July 2, 2017 by GeneralDisorder Link to comment Share on other sites More sharing options...
idosubaru Posted July 3, 2017 Share Posted July 3, 2017 yep, i always do it. pretty sure i've seen it happen many years ago when I first started doing headgaskets on XT6 engines carefully and paying attention to every step - maybe it happens if the head is installed with head bolts pointing horizontal as opposed to vertical - or only if too much lube or oil is used... Link to comment Share on other sites More sharing options...
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