I've been an Automotive Tech from way back in the 1980's. I have a background as a Machinist and currently work as a Technician in a hi-tech manufacturing facility. Your presentation is one of the BEST I've seen regarding TTY fasteners, Torque Angle, etc. My family has owned at least 10 Subarus over the years an still owns 3 that are 10 years old or more. All running great. You've always been a Go-To source for all things Subaru. Great job and thank you!

Wow... You sir are a scholar and a wizard amongst auto techs! Thank you for sharing your knowledge!

Very happy to know your opinion is something I can agree with. I have done a minimum of 50 Subaru head gasket or engine jobs in private shops and never once replaced head bolts. Never ever had a premature failure. 👍👍

@Mr. Subaru, This was exceptionally well explained! Great video and am looking forward to more! Especially if they can pertain to post 2008 Foresters in the future. Thanks again for all your work in sharing your knowledge! I actually like instructional videos where you do a detailed review of aspects of previous repairs. Just as a FYI of my view... I am not as interested in tool reviews from you, although they are excellent, because those are a dime a dozen on KZfaq. I come to your channel for Subaru content and Subaru content only. MUCH APPRECIATED!

i love these videos you make, i really can't wait to get a subaru

Awesome video as always. Very conclusive answer. I'm sure I'll be linking this to many misinformed people.

Great job! You answered all my questions!!! 👍👍👍 Keep doing what you do. Thanks!

Replaced head gaskets on 2001 fozzy 5 years ago. I didn't remove the engine from car , as there was enough room . I replaced head gaskets at 182,000 , now has almost 245,000

Great and informative vid mate! much appreciated.

totally not scatterbrained, actually easy to follow and understand. my confidence level to approach this job is definitely higher after watching. i just need to find a good machine shop in my area to take the heads to

Another great learning video. Less 60$ to spend on head bolts 👍👌😍😊 Thank you.

I’ll never get anywhere near that in depth with my maintenance or repair but it’s good to know.

Mr Subaru...You are an excellent teacher and really good at explaining the details and also showing examples of doing it. I have never owned or worked on a Subaru but your mechanic methods could apply to many applications l'm sure. I'm hooked on watching your videos and enjoy reading the comments.

Hello Mr Subaru, Great video, explaining key points on the tightening of the CH and very helpful when doing my Suby CH. The Tensile Stress-Strain presentation was very easy to follow and on point. Thank you for the video.

Very well explained. The use of mechanical fasteners is, in general, not well understood. I began to understand years ago when torquing the 3" diameter studs on a nuclear reactor cover plate using a heater in the hollow stud, a 50-ton bridge crane to stretch the stud while the nut was screwed down hand-tight. Crane tension released, nut/stud perfectly torqued to spec, no evil stuff able to leak out the seal.

Excellent Video learned a lot about subaru 2.5 issue thanks.

Very helpful indeed. Thank you 👍😊

The general rule is if it is a 'stretch bolt' aka TTY, to toss the fastener out. Its junk after it stretches. I run ARP'S on all my stuff so I reuse them all day. Good video, nice to see someone break down the B.S. better than I can lol

I have been following you for a while now but.... I ALWAYS learn something new (or confirm what I believed.. a tech for 38 yrs. Love Subaru. Never worked at dealership. So learned on the fly So once again thank you for teaching us and confirming things I love the videos and it's so nice to prove to somebody else that the bolts are reusable lol So many parts first say no they're not reusable...You have to buy new ones.... 😂

Such a wonderful video!!! Thank you so much!!!!!!!

Great info thanks for sharing!

Clear and concise, perfect

Yaaay! I got the correct answer in your poll. Thanks for the great video.

Muy Buena explicacion

Hey man your videos have been very informative was wondering how ypu feel about chasing the threads should help promote acurrate torque correct?

When i young I rebuilt a ej25. Did not know to oil threads for the head bolts. Freshly rebuilt block from machine shop. Hour later it went back. As I attempted to tighten the head bolts dry😞(SNAP!!!!) broken the bolt in two

Hi When I put my machined heads on the new Subaru Short block on my 2008 Subaru Legacy GT Turbo - I was pretty nervous about this whole area and bought new head bolts. The dealership mechanic said re-use old ones. Machine shop who did the heads said I was nuts to do that - and get new ones (they won out in my mind - I got scared). Heck, I still have the old ones. This is most helpful to know I didnt need to do that. Thanks!

I've reused them on the 2.5l at 170000. No issues, sold vehicle at 270000.

We don't replace them unless we have a creaking issue, and even then we just grab a HB out of the bin. wire wheel threads, oil threads, moly between the washers and your good.

Too long, but subject was well-covered. Two things: To really know if the bolts might actually stretch to yield (stay elongated) you must measure the actual bolt before and after, much like you measure rod bolts when tightening. It might even be possible to strip out the threads before you get to yield, but I doubt it unless the case threads have see a lot of use or the bolt threads were bad and damaged the case threads. Secondly, I wish you had mentioned the use of assembly lube (like ARP sells) and whether that is allowable for lubrication versus motor oil. I would think it would actually be better and give more consistent torquing due to less friction than with plain oil. The final tightening by degrees is dependent on the last torquing being accurate, even though it is a moderately low number and not a lot of friction is involved. Thanks for making the video!

Considering I found a broken factory torqued head bolt in lower cyl 4 position when I popped the heads off my ej205, I went ARP studs on the full rebuild

Absolutely GREAT video!!! Answers many questions with great details and facts. Yet I have more questions. Does Subaru ever use Torque-To-Yield bolts? If my Subaru has standard head bolts, are Torque-To-Yield bolts NOT recommended? If one purchases new Torque-To-Yield bolts, would the torque sequence / process be different from the official Subaru process? If so, where may I find the proper torque sequence / process for the Torque-To-Yield bolts?

Eric O. at SMA is trying to sell a lift if you're interested. I just know you're back to the dirt and this might be an option for when you get a building sorted. Only a few states away!

I've reused mine on my ej22t

Not only CAN you teach an old dog new tricks, an old dog can learn from a newer dog. The fact that this video set the record Straight regarding tty bolts is actually less significant for me. The greatest part, is that this gives me hope for the younger generations.

Is there a nice to see somebody on the internet that knows what he's talking about it puts a good joke in there and makes it so I can understand what I'm doing

When doing h/gaskets on my 98 WRX, I found using NEVER-SEEZ,pure nickel special, anti seize compound on h/bolts. Eliminates all grabbing and gives a beautiful smooth tightening transition. Been in engineering since 1970,and swear by this stuff. Cheers from Australia and my old REXY is still hammering!

When torquing bolts on my EJ25D I gauged the torque when turning the second 90 degrees. There was on average between 78 to 80 ft*lbs.

I've reused my EZ30 NA head bolts with no issue. I cleaned and deoiling them. Then oiled the thread. Spun on the manual with all the moments and twists. The bolt did not produce any creaks. And I wasn't first who did that with my EZ30.

Awesome. Case closed! I spent hours researching this topic when replacing the head gaskets on my first engine. I finally settled on reusing the bolts but because of all the conflicting info I was still nervous about it. Now doing a second engine and because of this video I have 110% confidence that reusing them is fine. Thanks man! One thing that would be interesting to know is what exactly is the difference between the corner and center bolts? Different grade steel or something? Also, why are they different in the first place? Because they're getting torqued to slightly different specs the bolts have to be different? Just curious about that...

Is there a difference when torqueing the composite gasket vs mls. Gettting ready to do heads in a non-turbo 2007 2.5, but I'm going to use the mls gaskets.

Hi wow Mr Subaru this is the go to video for us techs or DIY when doing heads I wanted to ask you how critical do you think having STIS if I was to strike out and do my own thing I still need to get a scan tool but I want to specialize in Subarus I will start very small just husling details with local Subaru owners and then see if I can do some diagnostics or engine work , How important is it to have STIS In a Subaru shop ?????? Thank you Subaru =unity NORTHERN BOXER TECHNOLOGIES (tm)

When I’m doing valve springs on the frs the Subaru part numbers can mix me up. I’m used to Toyota part numbers. Example is 12345-67890. The frs part numbers are like SU251AB253 for example

I am about to get a 2001 Subaru Outback limited version vehicle and need to replace the head gaskets. I was told that you can do that with the engine in the car but after watching a couple of videos including this one I've decided to take it to do this. Thanks for showing just how tricky it would have been - thanks for the information.

ShOcK & AWE outstanding Gear Head info. You R the "Subaru Whisperer" The check is in the mail.

Well I guess I'll pull out the new ones and put back the old ones! Darn could have bought some good beer! Glad I saved them.

Great video! Do you by any chance know if the procedure for the EE20 diesel (2011) is the same? Both in which way to tighten/ untighten and the amount of torque required? Greetings from Norway 🇳🇴

My wife inherited a 2012 4cyl. Outback with 50K miles. I noticed on one of your videos that you said a 2012 headgasket will eventually fail...it is just a matter of time. With that in mind, I am contemplating having the timing belt changed this summer because I have the belief that timing belts should be changed either at 80K or 8 years old. I acquired this belief from personal experience. IUO, when I have the timing belt changed, should I have the head gaskets changed too? Time and convenience are very important to me, and the expense is a tertiary concern. I would like to have your opinion.

I think what you're trying to say is that torque is only a measurement of the rotational force exerted to tighten the bolt. That's not directly measuring the actual clamping force it's putting on the head/gasket/block interface. So, since you can't directly measure that force, you just have to base it on the torque of the bolt, hence the angle measurement.

I’ve reused my head bolts once with no problem. Make sure you use a good amount of engine oil on the threads. Assembly lube would be better.

2ish I've would have known that... When I ordered head gasket set it strongly recommend to replace head bolts ... Would've saved money

Great videos and very informative! I know you said we need to torque first to squish then back bolts before final torque, assuming you're using the oe single layer steel vs the Subaru uncoated MLS gasket for EJ253 SOHC NA. But is the squish step necessary for the MLS type gaskets? I've heard some subi techs skip squish step. My 02 Honda civic 1.7 SOHC NA has MLS and it didnt call for a squish and final torque step. Per your recommendation, im going to be using the mls on my subi, the design is the same as their oe single layer steel gasket. Thanks for all the help and great videos

Hello grateful info one question what if you mix the bolt are there any differents

I torked mine to 50 ft than to 75 on outer and 80 on inter bolts.

Mr. Subaru, Do you have any recommendations for aftermarket studs for the torquing of studs (Allen head studs) in block,and then torques on the nuts. 2006 2.5 DOHC Baja turbo. Learning a lot from your videos. Keep up the good work.

hows it going man, may i ask if i need a new headgasket if i am replacing my headstuds and bolts with an aftermarket, sorry for the dumb question

You mentioned "lint" a few times, unless I misunderstood. What are you referring to?

Thanks again for sharing your knowledge with us good sir. So i have a naturally aspirated EJ25 that i'm doing the head gaskets on. While it's apart i was thinking of putting a turbo on it. I don't want to go too wild with it, cos it's a daily driver, but just wanna bring up the HP a bit. Would you still recommend doing the head stud upgrade to that?

Hey mr subaru again lol so I'm about to do the headgaskets on my car and ive seen a ton of different videos and forums on torque specs and if i need to get new head bolts, in my opinion your the smartest mechanic for the question on a 2010 subaru impreza ej253 should i replace all the headbolts and what are the torque specs and angles for a ej253 motor? Thanks your the best!

If there is any stretch I'd guess it is the AL female threads, not the steel bolts.

What's the best seal kit I can use for a turbo subaru?

Used factory bolts are better than new aftermarket bolts. Aftermarket bolts always have dinged up threads and are never as straight as genuine bolts. If you are anal buy new bolts from the dealer, otherwise inspect your old bolts and reuse them. Subaru changed the torque sequence over and over throughout the ej engine era although they are all essentially the same. It's all bs, Subaru engineers purposely used inferior head gaskets on all of the N/A motors, knowing that they will fail at 100k. All of the turbo motors use mls gaskets that never fail because the engineers knew they wouldn't make it through the warranty period otherwise. The dohc turbo mls gaskets actually fit the sohc N/A motors, if you use these they will never leak again. Oil the bolts well, use turbo gaskets and torque bolts to 80 lb-ft and they will never leak again.

Should the center head bolts always be visually different? My brother and I took his 06 forester apart and the head bolts are all identical to each other. It had Felpro head gaskets done on it bfor he bought it and not sure what’s going on in here. It was kind of janky work they did.

Should I replace my stock studs and bolts that hold my jpipe to the turbo on my 2020 wrx when replacing it with a cobb jpipe? It only has 16k miles.

How do I tell which side of the gasket goes which direction on the Subaru mls gasket?

What about light coat copper anti seize over oil coating?

Hi, I got a 2007 subaru outback 2.5L (non turbo) I'm experiencing pressurized cooling system. Some sweating oil on the bottom back of headgaskets but not major. Looks like the coolant is not mixing with the motor oil though. I got alot going on, gotta move from Arkansas to South Dakota in the next couple of weeks, so my question is, should I hurry and replace the headgaskets, or put some kind of stop leak in and do the headgaskets after we settled in up north? If I do go with the stop leak, what is the best to use?

Does it matter what kind of oil you use on the bolt? So just a thin layer on the spots you said?

Stock turbo application ok to reuse. Im not adding any horsepower.

what about the case bolts?

Just bought a SVX, Would love some content, also if you have any fenders laying around...

Mr. Subaru, my 120k miles, non-turbo 2.5 just started overheating. Ran a block test and only get combustion gasses in the radiator when the fans turn on. To me, this indicates that at a certain temperature, and only then, the problem appears. Is it possible that all I need to do is retourque the head bolts? If a head gasket is blown, it leaks at all temperatures, right? If so, can I just remove the valve covers. And do it relatively easily?

Same torque specs for turbo cars?

I just bought a 2003 Baja with bad head gaskets. To fix, I bought turbo head gaskets MLS from 2006 part number 11044AA642. Are these turbo gaskets going to be a permanent fix from your experience? Thank you.

Hey Mr. subaru, by any chance do you what's the best video on KZfaq for changing out my valve cover gasket on my 06 outback 2.5xt? also what gasket brand do you recommend? Thanks

Would this sequence work for a 2017 wrx sti?

How long should it take a competent mechanic to pull the engine out, do the head gaskets and the rear main seal at the same time? Just wanting to make sure I am not getting ripped off

Would it be cheap insurance to replace the bolts anyway? They can't be that expensive

I suppose that the ARP stud kits cost a lot more than a new set of factory head bolts (are people in the field substituting cheap new Chinese head bolts for the Factory item or are there counterfeit head bolts floating around out there ?) I guess the ARP studs come with their proper washers and nuts?

Although your information is true, I still always replace the head bolts when replacing a head gasket.

Is it safe to buy a 15 year old Subaru Legacy Outback with a 3.0 r

I’m assuming this is all done at the factory in Japan by computer robot and probably all the head bolts at the same time I’m sure instead of individually doing them🤷🏼‍♂️

Took motor apart and found all head bolts are silver thought mold should be black I didn’t do them last

one and done on boosted applications save yourself the headache and get arp studs

Hawn for president

Do you have a EJ25 DOHC head gasket replacement video?

When I hear "stretch bolt", I just take it as gearhead slang for a "torque to yield " bolt, but it is a misnomer. Every tension type fastener you tighten from a tiny woodscrew to the head bolts on giant ship diesels stretches. Everything is a spring of sorts, every material has a spring rate. 10 ft lbs on a 2" diameter bolt just doesn't stretch it much. Most bolts are tightened only within their elastic range, traditionally, and reaching the yield strength means you've permanently deformed it, it's junk. Intentionally doing this to a bolt, as in TTY, has become more common, it results in more consistent clamping force being achieved. Harder to overdo it, as the fastener will just continue to yield. But those reusable Subaru head bolts are most certainly stretching, and the head material under the bolt head is compressing/deforming. Just not permanently. Very nice rod bolts are sometimes tightened by measuring relaxed vs installed length...measuring the stretch. But that won't work on a head bolt in a blind hole. Angle torque is a variation on that method, since a certain amount of rotation will result in a known stretch, based on the thread pitch. The angle part of the torque sequence is unaffected by friction, other than you needing to pull harder to reach the needed angle. Stretch bolt is a bad description...the only bolt that is not stretched is a loose bolt.

*to much lught for the green screen. is making your beard green :) Thx for the info ;)

On my first HG job, I tried to use felpro head bolts, those things are such trash, as I was doing step 2 of the torque sequence, the bolt broke in half in the block........after I returned them I found out they were more expensive than factory bolts!..........strangely, my local subie dealer has drawers full of head bolts.....and I have seen invoices for HG jobs they've done, they do replace all 12 bolts, their techs must've bought into the stretch bolt lies too

Why do you have a green screen of a dealership shop behind you?

hey i got your head gaskets and head bolts on Amazon. Thanks! Question i got confused between foot lbs and NM in the manual. So i over torqued to 69 instead of 51 before i backed them up. and 34 instead of 25 on 1 & 2...do i need to replace the head gasket and start over? I hope i didnt damage the heads!

Question time. I do lots of head gaskets on single overhead cam ej251 motors at my shop. Due to the failure of the head gaskets leaking I replace them with the mls turbo gaskets. Do I use the tightening procedure for the quad cam motor or continue to use the procedure for the single overhead cam

What about ARP head studs? Does ARP make head studs for Subaru? Is that a better option?

Two of my bolts sh9ow surface rust on the shaft, do I need to replace?

Recall recall recall do the right thing stop polluting t environment

Sure you CAN reuse them, but what's the point when something that important is at stake and you can get new head bolt set for 40 bucks?

But where can I find a service manual for my subaru? Please...

can i use shellac on head gasket?

MrSubaru I ordered a head gasket for my now infamous 2007 outback i SOHC just want to confirm that i got the recommended new gasket is it 11044AA633?

The sequence at 10:24 is for new bolts correct and not for reusing old bolts?