Broken aluminum intake bolts

[entropy454]

My thermostat was leaking and I tried to loosen them up with PB Blaster and work them off. The seller gave me a thermostat and told me about using the anti-freeze greeze on the threads when I put a bolt in an aluminum intake. That should have been a warning to me that he had tried before and gave up.

Needless to say neither would move and the shorter of the two has not broken off. The bolts were either the original or very old. It broke below the intake line so I guess that means there is less to work out?

My worry is the bolt still intact. This is the stock 69 aluminum intake and I don't want to harm it. This intact bolt is in a raised tower and is screwed into more aluminum. Should I continue to try to unscrew the bolt or try to just drill it out also?

I plan on using reversible drills and a eazy-out kit. Does anyone know if they sell reversible drill bits at normal hardware stores like Lowes or Home depot?

thanks again and any suggestions are welcome.

jim

 

[6880 Mike]

I would go slowly with the existing bolt, giving the PB Blaster plenty of time to work.

Good luck.

 

[Hib Halverson]

For the broken bolt, my guess is the shank is still seized in the intake manifold. An E-Z out type product may work but, once the hole is drilled and you're ready to extract the bolt, you still have to deal with it being "frozen" in place. You'll need a good penetrant and maybe the application of some heat before you use the E-Z thingy to back the bolt out.

In the event that an E-Z out doesn't work, you'll need to drill what's left of the bolt out then insert the hole. Considering the value of an original, '69 alum. intake, I'd use a drill press for the drilling rather than a hand drill and the best insert process, by far, is "Time-Sert". See: Time-Sert.com

As for the other bolt, again a good penetrant left overnight is a good choice before you try to get it out.

I'm not familiar with "PB Blaster" but I do know the best penetrants in the business are either "Aero Kroil" or "Silikroil" both made by Kano Labs. Aero Kroil is common in the industrial and aerospace industries but, actually, is not too common amongst automotive enthuaists and DIY because it's not carried by a lot of mass marketers. I use Silikroil and I get it from the Eastwood Co but some "industrial hardware" stores carry it. See: KanoLabs.com

 

[entropy454]

Well the good news the broken bolt is recessed now. SO a nice pool of PB blaster has been sitting in a pool above the threads all night. The intact bolt is still on and the only way to spray the pentetrant on the head of the bolt and hope it sneaks in the edge.

 

[entropy454]

Where do you buy replacement bolts that look original? I don't think either one of these is going to come out with ease and in one piece.

 

[Rex S]

As a small but well equipped shop owner, my advice is remove the intake and take it to a machine shop. Those guys do that kind of repair every day and are very good at it. They can also install Helicoils (you won't see them after repair) which will make the intake better than new and far easier to get apart later.

 

[Vettehead Mikey]

As a small but well equipped shop owner, my advice is remove the intake and take it to a machine shop. Those guys do that kind of repair every day and are very good at it. They can also install Helicoils (you won't see them after repair) which will make the intake better than new and far easier to get apart later.

Where's the 'I agree' smilie? oops, wrong website. The chances of getting both bolts out while it's still installed on the engine and without ruining the manifold are slim. Spend the bucks and do it right.

Replacement bolts are available from Paragon.

 

[entropy454]

Are the bolts threaded threw the thermostat housing or are they just slid through them and than screwed into the intake?
I was wondering what would be holding the thermostat housing to the intake if the bolt heads were completetly gone?
thanks

 

[Dustoff529]

Agree

Sometimes you just gotta let somebody else do the job... a valuable rare piece with potentional for lots of damage.... Let teh PROS do it, maybe they will let you watch and do some educating you can use later but not on this project
"A man's got to know his limitations" Dirth Harry Callahan
When I have you rwounded
Charlie

As a small but well equipped shop owner, my advice is remove the intake and take it to a machine shop. Those guys do that kind of repair every day and are very good at it. They can also install Helicoils (you won't see them after repair) which will make the intake better than new and far easier to get apart later.

 

[gmjunkie]

Are the bolts threaded threw the thermostat housing or are they just slid through them and than screwed into the intake?
I was wondering what would be holding the thermostat housing to the intake if the bolt heads were completetly gone?
thanks

The bolts just pass through the housing,if the bolt heads were gone it should come off!!
I extract broken off bolts for other people all the time from Intakes,Heads,Engine Blocks,and Exhaust Manifolds!!(I rarely break one!)Haven't had to use a Helli Coil in years!!
Some are hard as hell,some come right out!!

1st thing, if I suspect it's going to twist off,Heat,Heat,Heat!!
(Not Cherry Red,If it's Red Hot wait till it has Cooled some,You don't want a Flam Up!):ugh:ugh:ugh
2nd as it's cooling Soak the heck out of it with PB Blaster or Kroil!!
(By the way,Hib's right Kroil is the Greatest thing since "Sliced Bread"!!
But PB Blaster works extremely well too!!)
As it cools it will suck the penetrant down the threads!
After mostly cooled I try to remove the bolt again,if it is still to tight,Heat down low and close to the threads as possible and try it!
If that don't work heat and soak again!!
If the bolts twists off the fun begins!!

I center punch the bolt in the center with a sharp hard punch,Needs to have a purdy deep dimple in it!(You must Drill striate and exactly in the center as possible!!)
I start with about a 1/16 left hand bit all the way through to the bottom!
(Go easy and don't break the bit or your purdy screwed!!):L
I then go to a 3/32 left hand bit,and then to a 1/8th left hand bit,and then to 3/16!! From there I try a left handed 1/4 milling bit with allot of pressure and it usually catches and whirls the remainder of the bolt out!!
If it don't I start using bigger bits till I can just barley see the threads and use a pick the get the bolt threads separated from the Block,Head or Manifold threads enough to use needle nose pliers to grab the bolt threads to peel them out counter clockwise!!

 

[entropy454]

How does heating affect the aluminum though in this case. Since it is two different types of metals? Can you melt the aluminum and damage it with heat from a normal small hand held torch?

 

[gmjunkie]

How does heating affect the aluminum though in this case. Since it is two different types of metals? Can you melt the aluminum and damage it with heat from a normal small hand held torch?

You don't need to heat it that hot,Aluminum usually doesn't take as much heat as steel!

 

[Shaggyvette]

Trust me Dude, these guys know what they are talking about. I broke a thermostat housing bolt this spring on the 82, and was without a car till I finally found another manifold. I cracked mine trying to get the easy out, out.. Unless you've done this before, just bite the bullet and pay some one to do it. I still have the old manifold, just to remind me not to tackle this job again.....:cool

Dave

 

[entropy454]

I sent it off to get fixed and got it back today. Started the process tonight of puting it all back on the car. They saved the housing, drilled out the manifold and put in helicoils.

 

[TimAT]

Glad you got it fixed; Here are a couple of things that nobody mentioned in the thread that do work:

1 Plain old Hoppe's #9 Gun Solvent is a really, really good penetrating oil. Works every bit as well as AreoKroil and available at Wal-Mart.

2 Sometimes broken bolts can be removed with a propane torch and a candle. Heat the area around the bolt (and the bolt) with the torch then apply the candle. the wax will get into the threads and sometimes you can turn the bolt on out.