I pulled my head off my 22R-E for the first time to do some well needed maintenance and seal up some exhaust leaks. When putting my camshaft back into my head the top half of the threads gave way on two of the holes where the camshaft caps bolt down. I tossed around throwing a Heli-Coil in but it looks like there's not a lot of meat there to comfortably put one in. I don't see anything in the FSM mentioning these but they look like inserts and I was wondering if there was anyway i could pop these out and throw some new ones in?

Here's exactly what I'm talking about just for clarification:

 

I had something very similar happen on my 3VZE; as I tightened the aft left side cam journal, the bolt kept turning. I backed it out, and wrapped around the bolt was what was clearly once a helicoil. Somebody had gotten in there years before. And that meant using a new helicoil was out of the question; a poor installation of the helicoil meant its threads, and the threads in the head, were now stripped out.

Fortunately, the hole is about 5 mm deeper than the length of the bolt (to make it easier to tap at the factory). I cleaned up the threads to the bottom with a 8-1.25 taper tap, then tapped it all the way to the bottom with a bottoming tap (I actually used a grinder to convert my taper tap to a bottoming tap). That gave me about 4 turns of "good" threads using a longer bolt. I was able to get a JIS Shoulder Bolt so it matches the others. The finish on the new bolts is shinier, a constant reminder to me to be very careful when torquing those bolts

 

Those steel inserts are nothing more than alignment dowels that lay in an oversize bore above the actual threaded hole.

They can, and in fact, Must, be pulled before any thread repair might commence.

There should be no reason a helicoil would not be a sound repair. Unless, like scope's head. Yours has been buggered before.

 

I like Scope’s repair guidance. Though i might choose a stud to eliminate concern about total bolt length.

 

You don't have a lot of clearance under the valve cover, so using a stud still requires some measurement. But a real advantage of a stud is that you only have to engage your sketchy re-created threads one time. You can use a lot of thread-locker. Then if you ever have to remove the bearing cap again, you're working with a visibly good nut on a good stud.

 

Right, the bolt is below the rocker girdle it seems, so that is the critical clearance. Agree on the threadlocker.

 

I really appreciate the advice and insight, all of those are good things to know and definitely ease my mind a lot. The one thing I'm stuck on now is I can't seem to get these alignment dowels out to do any kind of thread repair. What have you guys done in the past to get these off because right now I'm just trying to yank them out.

 

Had it happen on my 3vze like scope. Blind tapped, studded and pinned incase the nuts ever decided to wiggle loose. This cap had the indexer's like yours. Did require some measuring so the stud did not hit the baffling in the vavle cover. The torque spec is very little on the 3vze, like 12ftlbs if I remember correctly what is it on the 22?

 

14ftlbs for the 22R-E, I ended up getting those dowels with some help from a local machine shop now I'm surveying my options. Those studs seem really nice, I'm thinking I'll put some helicoils in and run some studs but I'll let you guys know what I ultimately end up doing.

 

Figured I'd update you guys, ended up converting my M8 x 1.25 tap to a bottoming tap and tried to clean up as many threads as I possibly could and got some bolts that are marked as 30mm long. With some very careful tightening I was able to cinch them all up to the factory torque spec. For future reference I took down the sizing information and the clearance I have from the cap and the rocker arm assembly and I plan on putting in some studs.Thank you guys for all the advice and help, you made this nightmare job a lot less stressful!!!

 

Glad you got it fixed.🤟🏻

 

That's the fix I used. You do have to be careful that the bolts aren't bottoming out; then your torque is just bottoming the bolt, not holding the cam cap. I'm not really sure how to check that, but you might try to get your thinnest feeler gauge under the head of the bolt.