Stripped Upper Air Plenum Screws for Throttle Body.

[Pierce]

Has anyone successfully repaired these? Mine spin freely. Any tricks or wisdom?

 

[bigredmachine]

you coud oversize it and use a hilicoil or something along those lines. as for getting them out if you can get something back behind the head of the bolt and give it a little pressure you should be able to get them out

 

[Pin_Head]

Timesert or helicoil. If you drill them out using a V block as a guide to keep the drill square, you won’t have to remove the manifold.

 

[Pierce]

I can remove them easily. Just can’t torque them. I’ve got a helicoil on order. @Pin_Head could you educate me on what a v block is please?

 

[Pin_Head]

Let me Google that for you. A V block keeps your drill square to the flange.

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[Pierce]

Thank you @Pin_Head

 

[Pierce]

I’ll provide some knowledge for the next poor fool that makes the same mistake I did.

The two steel inserts on top of the upper air plenum for throttle body are a press fit. Remove them by rotating them slightly while pulling. I marred mine during extraction so in the end the ugly part got tapped back into the upper air plenum. Out of sight out of mind.

ere are some options.
Helicoil and Time-Sert

I chose the Time Sert and some 20mm stainless inserts for (hopefully) overkill. The kit comes with some 10mm carbon steel inserts which would likely be more than adequate.

For the upper bolt holes the Sert guide is mostly useless.
Install is very easy.
1-Drill the upper plenum treads out as strait as possible; go until you hit bottom.
2-Thread the hole until you hit bottom; it’s aluminum, very easy.
3- The chamfering tool will not fit in the hole and is not needed; don’t sweat it.
4- Install the Time Sert; you should have plenty of room to fully expand it if you drilled the hole all the way out.
5- Re-install your new gasket and throttle body or supercharger tube thing.

I am generally a screw up when it comes to mechanicing and I pulled the thread repair off in 30 minutes with no issues. I was able to torque everything down to 15 ft lbs. I did not go the helicoil route because they (are rumored to) occasionally unscrew with the bolt. There’s no way to glue them in with thread locker.

 

[tetonshaggy]

How do you remove the pressed inserts from the manifold for helicoil repair?

 

[Pierce]

I honestly didn’t remember creating this thread. If I know me I would have stuffed a bunch of paper towels into the plenum intake to prevent a painful oopsie, grabbed onto it with a pair of channel lock plumbers pliers, twisted it while pulling it out while paying close attention to not collapsing it. I don’t have any painful memories of this one so it’s probably pretty easy.

The good news is that the repair is still going strong almost 6 years later.

 

[Fj80oregon]

How do you remove the pressed inserts from the manifold for helicoil repair?

View attachment 4133461

Use a stud or something close to the ID inserted so you don’t squish them to bad and use some vise grips or knipex to twist and pull out.

 

[robnicko]

I had to do a helicoil on a cam cap thread where the thread was beneath a guide collar like that and used one of these to slowly grip into it and then levered it out.
worked fine and didnt wreck the guide so it went back in no problem.

just screw it into the guide until it has a good hold and lever up against the hex head and a block of wood on the other end

 

[reklund5]

I have a couple upper plenums available if someone needs...