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-   -   Retorqing the head bolts. (https://www.ft86club.com/forums/showthread.php?t=146660)

irax 08-27-2021 10:32 AM

Retorqing the head bolts.
 
* EDIT for people searching in the future *
Depending on the manufacturer of head gasket you do not need to retorque head bolts.
TYPICALLY multilayer METAL head gaskets do not need to be retorqued.
Almost all head gaskets for the FA20 worth getting are muti-layer metal and don't need to be retorqued.

Irace86.2.0 08-28-2021 02:08 AM

Quote:

Originally Posted by irax (Post 3460460)
I tried searching for an answer to this and I couldn't find anything. :search:
But I wanted to double check, is the only way to retorque the head bolts is by removing the cams and cam girdles ? It doesn't look like there is enough room to get a crows foot in there otherwise.

There is a valve cover, cam retainers and a cam girdle/carrier, and then the heads that have the valves, rockers and spring assemblies. I think once you remove the valve cover you can remove the whole cam assembly to get to the head studs, but I don’t think you can get to the head studs without removing the carrier. I don’t think you need to remove the cam retainers separately. Just remove the whole upper and lower cam assembly as one piece. I think you will be removing some 12mm bolts to remove the entire cam assembly. If you remove the 10mm bolts then you will be removing the cam retainers and the cam shafts will come out separately from the cam carrier, and you still won’t have access to the head studs.

The head studs are 12 point 14mm torque to yield (TTY) bolts. Some say it isn’t good to re-torque TTY bolts multiple times, while others say it is fine. Just saying.

irax 08-28-2021 03:01 AM

So, to retorque the heads I need to remove the timing cover, the timing tensioners, the timing chains, the the cam girdle carrier with cam and retainers as one piece, retorque the heads, re assemble, re set the timing? I just want to make sure there is no other way around it.

humfrz 08-28-2021 03:55 AM

Quote:

Originally Posted by irax (Post 3460460)
I tried searching for an answer to this and I couldn't find anything. :search:
But I wanted to double check, is the only way to retorque the head bolts is by removing the cams and cam girdles ? It doesn't look like there is enough room to get a crows foot in there otherwise.

I must ask (sorry) - why do you want to retorque the head bolts?

:iono:

irax 08-28-2021 11:22 AM

Quote:

Originally Posted by humfrz (Post 3460747)
I must ask (sorry) - why do you want to retorque the head bolts?

:iono:

You need to retorque the head bolts after assembling the motor after rebuild.

humfrz 08-28-2021 04:35 PM

1 Attachment(s)
Quote:

Originally Posted by irax (Post 3460796)
You need to retorque the head bolts after assembling the motor after rebuild.

Oh, I reckon I'm behind - :sigh:

Back in the day, when rebuilding an engine, we used to torque the head bolts down "on the way out" of the rebuild. NOT after the job was done - :iono:

Yep, torque the head bolts down, adjust the valves, replace the valve cover then crank that puppy up - :happyanim:

:popcorn:

Irace86.2.0 08-28-2021 05:02 PM

Quote:

Originally Posted by humfrz (Post 3460866)
Oh, I reckon I'm behind - :sigh:

Back in the day, when rebuilding an engine, we used to torque the head bolts down "on the way out" of the rebuild. NOT after the job was done - :iono:

Yep, torque the head bolts down, adjust the valves, replace the valve cover then crank that puppy up - :happyanim:

:popcorn:

He might mean after breaking the engine in.

humfrz 08-28-2021 05:08 PM

Quote:

Originally Posted by Irace86.2.0 (Post 3460871)
He might mean after breaking the engine in.

Ahhhh ....... OK.

:thanks:

irax 08-28-2021 05:15 PM

Quote:

Originally Posted by Irace86.2.0 (Post 3460871)
He might mean after breaking the engine in.

Exactly!

blsfrs 08-28-2021 06:16 PM

Am I reading this correctly? I have never heard of anybody re torquing subbie heads after a rebuild. Can you even access to the bolts with engine in the car? Not to mention, to get the cams out, you would have to take apart the timing cover, then retime the engine and reset the lash of all 16 valves.

Irace86.2.0 08-28-2021 08:14 PM

Quote:

Originally Posted by irax (Post 3460739)
So, to retorque the heads I need to remove the timing cover, the timing tensioners, the timing chains, the the cam girdle carrier with cam and retainers as one piece, retorque the heads, re assemble, re set the timing? I just want to make sure there is no other way around it.

Are you pulling the motor?

Maybe follow this, but I could have sworn I saw something where someone removed the cams or something without pulling off the timing cover.

https://www.ft86club.com/forums/showthread.php?t=103339

irax 08-28-2021 09:03 PM

Quote:

Originally Posted by blsfrs (Post 3460886)
Am I reading this correctly? I have never heard of anybody re torquing subbie heads after a rebuild. Can you even access to the bolts with engine in the car? Not to mention, to get the cams out, you would have to take apart the timing cover, then retime the engine and reset the lash of all 16 valves.

With other engines you retorque the headbolts after the first heat cycle. I have emailed the maker of the headgaskets to see if its something they recommend for their product but I have yet to get an email back.

blsfrs 08-29-2021 10:38 AM

Quote:

Originally Posted by irax (Post 3460919)
With other engines you retorque the headbolts after the first heat cycle. I have emailed the maker of the headgaskets to see if its something they recommend for their product but I have yet to get an email back.

A several years ago the EJ205 in my 2000 Impreza blew a head gasket. I had a local subbie guy plane the heads and reassemble the engine. No re torquing was recommended. A couple of years ago I had an FA20 built by Element Tuning. Again, no re torquing recommended.



Definitely, wait for word from maker of the head gaskets before proceeding.

irax 08-29-2021 05:24 PM

Quote:

Originally Posted by blsfrs (Post 3460994)
A several years ago the EJ205 in my 2000 Impreza blew a head gasket. I had a local subbie guy plane the heads and reassemble the engine. No re torquing was recommended. A couple of years ago I had an FA20 built by Element Tuning. Again, no re torquing recommended.



Definitely, wait for word from maker of the head gaskets before proceeding.

Yeah this is the first subie engine that I have had rebuilt so hopefully this thread will others in the future as well.


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