Welcome to the North American Subaru Impreza Owners Club Friday March 29, 2024
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Subaru Models > Legacy Forum

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 03-21-2006, 02:35 PM   #1
pilfflip
Scooby Specialist
 
Member#: 40484
Join Date: Jul 2003
Chapter/Region: NWIC
Location: Salem, OR
Vehicle:
'02 Murdered WRX
'02 Silver Legacy

Default head bolt torque specs

I'm getting ready to disassemble my engine for the head gaskted job.

I need to know where I can find the torque specs for the head bolts and it would be nice if i could get them for other fasteners on the egine as well. Does anyone know where I could get a spec sheet or download one?

...actually, a Chilton or Haynes should have that huh?


~Mike
* Registered users of the site do not see these ads.
pilfflip is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 03-21-2006, 04:03 PM   #2
Speedwagon
Scooby Specialist
 
Member#: 19681
Join Date: Jun 2002
Chapter/Region: RMIC
Location: Denver, CO
Vehicle:
1998 Legacy Wagon GT
Green

Default

Haynes has it. But it's not so much a spec, as a procedure/ritual.
Speedwagon is offline   Reply With Quote
Old 03-21-2006, 04:10 PM   #3
wrx_driver_2002
Scooby Specialist
 
Member#: 25952
Join Date: Oct 2002
Chapter/Region: NWIC
Location: Under your hood :-)
Vehicle:
1995 Impreza Coupe
w/ "Extras" :-)

Default

I can give you whatever torque specs you want. If you need anymore Just ask

Intake Manifold Bolts: 18 Ft Lbs
Crankshaft Bolt: 101 Ft Lbs
Camshaft Bolts: 61 Ft Lbs
Flywheel Bolts: 55 Ft Lbs
Timing Belt Idler Botls: 30 Ft Lbs
Timing Belt Tensioner (8mm Bolts): 18 ft lbs
Water Pump: 44 in lbs
Oil Pump: 44 in lbs
Cam Support or Rocker Shaft (8mm): 18 Ft Lbs



Loosen Headbolts in this order:

1 5 4
3 6 2

Tighten Headbolts in this order:

3 1 6
5 2 4

Following the tightening order, torque Head Bolts as following:

1. Torque All to 22 Ft Lbs
2. Torque all to 51 Ft Lbs
3. Loosen all 180 degrees
4. Loosen all 180 degrees
5. Torque Center Two bolts to 25 Ft Lbs
6. Torque Outer 4 bolts to 11 Ft Lbs
7. Tighten all bolts 90 degrees
8. Tighten all bolts 90 degrees again

Make sure you tighten all of them down the first 90* and then go back and tighten them another 90*. Also make sure you put some lube between the bolt and the washer, and put some sealant on the bolt threads. We use GM Thread Sealant.
wrx_driver_2002 is offline   Reply With Quote
Old 03-21-2006, 10:55 PM   #4
ballitch
Scooby Specialist
 
Member#: 74907
Join Date: Nov 2004
Chapter/Region: NWIC
Location: salem, OR
Vehicle:
98 cam'd EJ251
Wrx Tranny,slowr than ish

Default

why the difference in torque readings from inner bolts to outer bolts? and why torque them down to 51 ft. lbs. and then back off to only 11 ft. lbs.? seems a little light to me but how the hell should i know. also, i heard that suby head bolts are stretch bolts and should be replaced when doing HG's. but ive also heard that that info is B.S. and some people use head bolts 5 or 6 times and nothing happens. any info is appreciated.



~Josh~
ballitch is offline   Reply With Quote
Old 03-22-2006, 12:22 AM   #5
wrx_driver_2002
Scooby Specialist
 
Member#: 25952
Join Date: Oct 2002
Chapter/Region: NWIC
Location: Under your hood :-)
Vehicle:
1995 Impreza Coupe
w/ "Extras" :-)

Default

Quote:
Originally Posted by ballitch
why the difference in torque readings from inner bolts to outer bolts? and why torque them down to 51 ft. lbs. and then back off to only 11 ft. lbs.? seems a little light to me but how the hell should i know. also, i heard that suby head bolts are stretch bolts and should be replaced when doing HG's. but ive also heard that that info is B.S. and some people use head bolts 5 or 6 times and nothing happens. any info is appreciated.



~Josh~
I've never questioned Subaru's torque sequence. It does seem a little extensive and odd, but it's what the engineers found out worked best, plus it's always worked perfectly for me, so I've had no reason to deviate. When you torque subaru head bolts to the final torque specs, you're actually using angle torque (That's why you turn them all 90* once, and then 90* again after those low torque numbers) I would assume you are somewhere around 80 ft lbs on the center bolts and 70 ft lbs on the outer bolts by the time you're done with your angle torque steps. It would make sense to me that the angle torque compensates for the stretch of the bolt. I've only had to replace headbolts once, and that was because the person who put the engine together the last time didn't use any sealant on the threads of the bolts, and he didn't torque them down correctly so coolant got down into the threads and rusted the bolts.
wrx_driver_2002 is offline   Reply With Quote
Old 03-22-2006, 01:32 AM   #6
ballitch
Scooby Specialist
 
Member#: 74907
Join Date: Nov 2004
Chapter/Region: NWIC
Location: salem, OR
Vehicle:
98 cam'd EJ251
Wrx Tranny,slowr than ish

Default

good to know, thanx.

~Josh~
ballitch is offline   Reply With Quote
Old 12-27-2014, 10:27 AM   #7
2003wrx64
Scooby Newbie
 
Member#: 171615
Join Date: Feb 2008
Location: North Carolina
Vehicle:
2003 WRX

Default

No sealant is needed on the head bolts. The Subaru manual says to use engine oil to lube the bolt. Always lube the whole bolt, including the threads and both sides of the washer. Heavier oil works best. The only way coolant can get to the bolts is if the head gasket is already failing. The initial torquing of the head bolts is to compress the head gasket. This insures that the final torque sequence is accurate and not just compressing the gasket. If the bolts creak and pop while torquing, you need more lube on the bolt. If you are at the beginning of the torque sequence when the bolt creaks, start over from the beginning after relubing the bolt. If the bolt creaks after you have started the final torque procedure (25 lbs-ft on the center bolts, 11 lbs-ft on the outer) restart the procedure at the point where you loosen all bolts 180 degrees and all bolts again 180 degrees. In case of a stubborn creaking bolt, a bit of anti-seize usually does the trick. Also, make sure the bolt holes are super clean before beginning. Brake clean and compressed air work best. If you don't have compressed air, allow plenty of drying time after brake-cleaning the holes.
2003wrx64 is offline   Reply With Quote
Old 12-27-2014, 10:48 AM   #8
Patrick Olsen
Scooby Guru
 
Member#: 120
Join Date: Jul 1999
Chapter/Region: AKIC
Location: Where the Navy sends me...
Vehicle:
1997 Legacy 2.5GT
1996 Impreza coupe

Default

Hopefully the OP hasn't been waiting for almost 8 years until someone provided that information.
Patrick Olsen is offline   Reply With Quote
Old 12-30-2014, 09:13 AM   #9
Charlie-III
NASIOC Supporter
 
Member#: 30669
Join Date: Dec 2002
Chapter/Region: Tri-State
Location: USA, North NJ, 07456
Vehicle:
1998 Legacy 2.5GT
Silver Sleeper BK, 5MT

Default

Quote:
Originally Posted by Patrick Olsen View Post
Hopefully the OP hasn't been waiting for almost 8 years until someone provided that information.
True statement.......

Do the NA guys still use the FI torque specs for the HG's? It's what I started doing a long time ago once the "new" (back then) HG's came out.
Charlie-III is offline   Reply With Quote
Old 01-26-2016, 09:41 PM   #10
SR 25 RS
Scooby Specialist
 
Member#: 97983
Join Date: Oct 2005
Chapter/Region: BAIC
Location: Oakland
Vehicle:
2017 STi
Silver

Default

I learned a valuable lesson about inch pounds

Inch pounds VS foot pounds. Be warned future folk, pay attention to the spec measurment unit lol
SR 25 RS is offline   Reply With Quote
Old 01-27-2016, 08:38 PM   #11
Hardware BoB
Scooby Newbie
 
Member#: 429778
Join Date: Sep 2015
Default

Quote:
Originally Posted by SR 25 RS View Post
I learned a valuable lesson about inch pounds

Inch pounds VS foot pounds. Be warned future folk, pay attention to the spec measurment unit lol
That sounds like an expensive mistake!
Hardware BoB is offline   Reply With Quote
Old 08-21-2020, 05:13 PM   #12
Trapgarage
Scooby Newbie
 
Member#: 517945
Join Date: Aug 2020
Default Still doing it in 2020

I've browsed a few threads on head bolt specs and they all seem similar. Some say 14ft. Pounds on the outside bolts some say 11. I do 14 myself. I imagine they might snap or really stretch if over torqued when the head expands. Tried the copper gasket spray too once, I don't trust it, had to swap heads for avcs heads and when I took it apart it was still not cured weeks later. Maybe in a tight situation I would try it again but I'd let it cure completely dry first. Gaskets didn't fail in that 1 month period though but I think they may have eventually.
Trapgarage is offline   Reply With Quote
Old 01-16-2021, 08:38 AM   #13
tom1031
Scooby Newbie
 
Member#: 521707
Join Date: Jan 2021
Default

Quote:
Originally Posted by wrx_driver_2002 View Post
I can give you whatever torque specs you want. If you need anymore Just ask

Intake Manifold Bolts: 18 Ft Lbs
Crankshaft Bolt: 101 Ft Lbs
Camshaft Bolts: 61 Ft Lbs
Flywheel Bolts: 55 Ft Lbs
Timing Belt Idler Botls: 30 Ft Lbs
Timing Belt Tensioner (8mm Bolts): 18 ft lbs
Water Pump: 44 in lbs
Oil Pump: 44 in lbs
Cam Support or Rocker Shaft (8mm): 18 Ft Lbs



Loosen Headbolts in this order:

1 5 4
3 6 2

Tighten Headbolts in this order:

3 1 6
5 2 4

Following the tightening order, torque Head Bolts as following:

1. Torque All to 22 Ft Lbs
2. Torque all to 51 Ft Lbs
3. Loosen all 180 degrees
4. Loosen all 180 degrees
5. Torque Center Two bolts to 25 Ft Lbs
6. Torque Outer 4 bolts to 11 Ft Lbs
7. Tighten all bolts 90 degrees
8. Tighten all bolts 90 degrees again

Make sure you tighten all of them down the first 90* and then go back and tighten them another 90*. Also make sure you put some lube between the bolt and the washer, and put some sealant on the bolt threads. We use GM Thread Sealant.
Ok, so this is 15 years after this original post, but I like to be sure information is correct for anyone that might need to know. There is no reason to use thread sealant on these threads. And in fact you’ll just make it harder if you ever have to remove them again in the future. And it happens more than you might think. Engine oil, or in some cases anti-seize is what you will want to use. Coolant doesn’t ever get to the threads and the threaded holes are blind holes unlike a lot of engines that go through to a coolant passage.
tom1031 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
head bolt torque specs and pattern?? sekretskwirl Built Motor Discussion 8 03-02-2014 11:37 PM
Head Bolts & Cams Bolts Torque Specs Imprezd Factory 2.0L Turbo Powertrain (EJ Series Factory 2.0L Turbo) 3 03-20-2003 07:30 AM
A/T oil pan bolt torque spec? GPH993 Transmission (AT/MT) & Driveline 1 02-24-2002 05:17 AM
2002 2.5 RS bolt torque specs jdsimpreza Normally Aspirated Powertrain 0 02-12-2002 10:10 PM
Bolt torque spec, coilovers ????? Branwell Brakes, Steering & Suspension 5 10-19-2001 05:53 PM

All times are GMT -4. The time now is 11:50 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2024 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.

When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission
Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.