Intake manifold bolts

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AuroraGirl

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So, some of you may know my intake manifold has about 3 bolts that are either not all the way in, snapped off, or i stopped turning because it felt like it was gonna snap.

I would like to tackle this problem, as im finally tacking my heater hoses and gonna put some new belts on, it would be a good time to handle this. I can extract the sheared bolt, no problem, but what should I do to fix this? Should I buy new bolts(are they sold in a kit?). The three that arent all the way in, im not sure if the previous manifold installation cross threaded them or perhaps the bolts were weak from my impact removing them? Id hate to buy new bolts just to be in the same situation. Maybe threads are dirty? Im not sure if the bolts bottom out in the block or what, but maybe find a tap set and see if the threads go down nicely?

If using a tap to check the threads, can anyone tell me a size or recommend a good tap set? Never done this before.

Or, perhaps, I should tape the hole to the next size bolt? I havent done that before either but no better day to learn than today, I guess.

And, in the end, should i use PTFE on the threads? Two of the three bolt holes leak coolant, and if they still leak after i fix the bolts ill live with it, but maybe thats causing the leak(the bolt not being all the way in). If anything apply the even pressure on the manifold, since 2 bolts are near eachother.
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As seen here, one bolt i never went all the way in. The bolt hand threaded real nice, and it got very very difficult to turn anymore quickly, so i never finished turning the bolt. I didnt want to repeat the one i broke the head off. This side never seemed to have a leak problem.

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The coolant present in this picture is not actually from the bolt, it was from when i had to tighten the thermostat housing because it was loose, so some coolant spilled. However, you may notice the missing bolt, well its there just not applying any force on the manifold. The one with coolant around it was the one i could not comfortably tighten without it feeling like the bolt was gonna give. Its mostly down, but its not applying much force down.

All other bolts went in nice and tightened nice.
 

Ricko1966

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You have to determine the problem before you can pick a solution.Remove all offending bolts
Check the threads.None stripped? Great ! Some stripped buy a helicoil kit. Now buy an after market 12 point bolt kit or go to the hardware store and buy some grade 8 hardware r&r the bolts one at a a time and seal with liquid Teflon As for removing broken bolts, whats your plan. Do not say ez out.
 

AuroraGirl

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Its why I asked whats a good way to find the problem. Like I said, would getting a tap and seeing if it freely navigates the threads work? There is only one broken bolt, but because its cut flush with the manifold I cant use a vice grips. Wouldnt an ez out be the best choice, because the only other solution that i can think involves removing the intake and i really dont want to repeat that job, that was hot, sticky, and I had a hell of a time reaching the thing. i want that to be last resourt, i guess. I dont have a welder working so no attaching a bolt to whats left.
 

Ricko1966

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I HATE!!!! EZ outs.At least once week some clown would carry in something with an EZ out broke off in it.Now I have to remove the broken EZ out, Now I have to try to redrill the off center crooked hole so I can retap the hole. My first attempt is try to walk it out with a dull punch.my 2nd go to is weld a washer and nut to the offending piece. If I'm going to drill a hole as in for an EZ out just drill the correct size hole to tap it.If you are lucky now you can just collapse the shell of remaining bolt and pull it out. Okay I left methods out and EZ outs aren't that bad in the right hands but if it's stuck it's stuckk and turning the EZ out harder isn't going to un stick it.
Next on the to do list take 1 known good intake bolt to the hardware store buy 1 stainless or grade 8 equivalent 1/2 longer.Take it home grind a flat spot on the threads about 1/2 inch long and all the way through the threads on one side.You now have a handy thread chaser.clean all the bolt holes with it.But just r&r 1 bolt at a time the chaser will identify messed up bolt holes.
 

AuroraGirl

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I HATE!!!! EZ outs.At least once week some clown would carry in something with an EZ out broke off in it.Now I have to remove the broken EZ out, Now I have to try to redrill the off center crooked hole so I can retap the hole. My first attempt is try to walk it out with a dull punch.my 2nd go to is weld a washer and nut to the offending piece. If I'm going to drill a hole as in for an EZ out just drill the correct size hole to tap it.If you are lucky now you can just collapse the shell of remaining bolt and pull it out. Okay I left methods out and EZ outs aren't that bad in the right hands but if it's stuck it's stick and turning the EZ out harder isn't going to in stick it.Take 1 known hood intake bolt to the hardware store but 1 stainless or grade 8 equivalent 1/2 longer.Take it home grind a flat spot on the threads about 1/2 inch long and all the way through the threads on one side.You now have a handy thread chaser.clean all the bolt holes with it.But just r&r 1 bolt at a time the chaser will identify messed up bolt holes.
Are you saying not have threads 360 degrees around the bolt, to have flat spots? Wouldnt that mess up the threads so they would want to start?
 

Ricko1966

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Believe me it works like a champ.The dirt and chips collect on the flat.Look at a tap it doesn't have threads 360 degrees. Grind a. Flat spot through the threads 1/2 long in 1 spot.


Google search BOLT brand thread chasers.You will see them on Amazon and EBay red bolts 2 packs.. Same concept I grind a flat on the end of a stainless bolt.Stainless is hard it works good throw it in the tool box for future occasions.
 
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AuroraGirl

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I do believe what youre saying, but im just struck that by grinding off a section the threads stay good and dont have alignment or fitment issues, like if you cut a bolt with bolt cutters, the threads wouldnt be good most likely.
 

AuroraGirl

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But do you think I have debris in my threads or do you mean to use it as a way to see if the threads are.. well.. threads and arent crossed or bind in anyway?
 

Ricko1966

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Either or it doesn't matter that will clean out debris and cleanup mildly buggered threads.

I"m telling you it works ,grind a flat spot and get after it.

If you cut a bolt with cutters you deformed the threads and the bolt. Grinding a section away leaves nice even unmolested threads and 80 percent are still there to guide, etc. You've just added a spot for trash to collect.
 

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I'd pull the manifold to be able to grab that broken bolt with Vice-Grips, or a small pipe wrench. Plus it would be easier to address the other bolt problems.
 

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