CJAA Head Bolt Upgrade (First time questions)

[WWJSWD]

Upgrading to 12.9 head bolts is coming down the line for me. So I've got some dumb questions,

1. Are there any precautions when removing the old head bolts?
2. I'll work from the outside in, and slowly break them loose.
3. I'm not replacing the head gasket, so should I remove the timing belt so the head isn't under tension at one side? Is there enough downward force from the timing belt to lift the driver side of the head?
4. I'll used compressed air to blow out any oil from the bolt holes.
5. After the old bolt is removed, the bolt hole cleaned, should I immediately install and hand tighten a new bolt? (This is based my worry about unseating my head gasket)
6. For reinstalling the injectors, is there anything else needed beyond the following kit? https://www.idparts.com/fuel-injector-install-kit-cbeacjaa-n90427502-wht000884-059130519-03l103113-p-16165.html


Anything I'm missing?

Thanks!

 

[Mozambiquer]

Upgrading to 12.9 head bolts is coming down the line for me. So I've got some dumb questions,

1. Are there any precautions when removing the old head bolts?
2. I'll work from the outside in, and slowly break them loose.
3. I'm not replacing the head gasket, so should I remove the timing belt so the head isn't under tension at one side? Is there enough downward force from the timing belt to lift the driver side of the head?
4. I'll used compressed air to blow out any oil from the bolt holes.
5. After the old bolt is removed, the bolt hole cleaned, should I immediately install and hand tighten a new bolt? (This is based my worry about unseating my head gasket)
6. For reinstalling the injectors, is there anything else needed beyond the following kit? https://www.idparts.com/fuel-injector-install-kit-cbeacjaa-n90427502-wht000884-059130519-03l103113-p-16165.html


Anything I'm missing?

Thanks!

Only do one at a time and torque it before moving on to the next.
You will have to pull the cams and timing belt to be able to pull the head bolts iirc.
You're also supposed to replace the spring clamps for the injectors when they are removed. Like what this kit from FCP shows. Cjaa injector install kit

 

[WWJSWD]

Awesome thank you for the advice! The FCP euro kit looks much better equipped! I’m finding conflicting information if the cams need to come out. I’ll see what my Bently manual shows for the head bolts. Great point about going one at a time. I’ll follow the tightening pattern, pull #1, blow out the bolt threads with compressed air, then drop in new bolt and torque to first spec. Once all 10 are in following that sequence I’ll go through standard second torque spec sequence and so on for the two final 90 degree turns.

 

[p.e.fletcher]

The cams do NOT need to come out to do the 12.9 bolts, only if you’re doing studs because not enough room for that socket. Neither does the belt - you rotate the cams to expose the notches to access the bolts.

You want to do the whole procedure on each bolt before moving to the next so that you do not disturb the clamping force on the head gasket. Start from the inside bolts and move to the outside bolts.

1. 30nm
2. 50nm
3. 90 degrees
4. 90 degrees

Don’t forget a valve cover gasket in addition to the injector kit. The nuts and bolts aren’t actually required to be replaced so I sourced the fuel injector parts individually for a much better deal than the kits. I did opt for new seal plates and I think ECS had them for like $11 each at the time.

From Erwin:

“The following components, seals or O-rings must be replaced during each removal and installation, or when a fuel injector is being replaced: "Tensioning plate", "copper washer", "fuel injector shaft O-ring" "fuel injector return O-ring".

 

[WWJSWD]

The cams do NOT need to come out to do the 12.9 bolts, only if you’re doing studs because not enough room for that socket. Neither does the belt - you rotate the cams to expose the notches to access the bolts.

You want to do the whole procedure on each bolt before moving to the next so that you do not disturb the clamping force on the head gasket. Start from the inside bolts and move to the outside bolts.

1. 30nm
2. 50nm
3. 90 degrees
4. 90 degrees

Don’t forget a valve cover gasket in addition to the injector kit. The nuts and bolts aren’t actually required to be replaced so I sourced the fuel injector parts individually for a much better deal than the kits. I did opt for new seal plates and I think ECS had them for like $11 each at the time.

From Erwin:

“The following components, seals or O-rings must be replaced during each removal and installation, or when a fuel injector is being replaced: "Tensioning plate", "copper washer", "fuel injector shaft O-ring" "fuel injector return O-ring".

This is great advice thank you very much! Excellent point about fully tightening each bolt as you go so I don't loose clamping force on the head gasket.