Why did this happen installing my lower intake?

[pwcracer]

Why did this happen installing my lower intake? (Update)

I did everything like I was told, I had the fel pro gaskets tacked in to the heads, I had a 1/4 inch tall bead of RTV on the ends, and I was torquing down the bolts in the specified order. I first went to 1 foot pound, then 13, then 25 to finish it. When I got the the bolt to the right of the dizy, (Front right corner) the stupid bolt broke off in the head before I hit my torque reading! I pulled the intake off and another thing I thought was funny is that the RTV in the ends looks as though it was never touched, there was none on the intake either.. Now I have to e-z out the bolt if I can, and buy new bolts, I think I will go with the strongest grade bolt I can find.

If i ever get this resolved, do I have to use new intake gaskets?

 

[Black 93 Fox]

You should be able to reuse them. Get some good grade 8 bolts i guarantee thoes wont break and if they do your doing something really stupid.

 

[Curse]

Were the bolts in bad shape? On my friend’s car the bolts looked corroded; he was being hardheaded and did not want to buy new bolts. On the first bolt at 13 foot pounds it snapped.

 

[tmoss]

yep, they corrode and get weak

 

[StangFireman]

You might want to run a tap down the bolt holes also. I've seen some corrosion in the bolt holes before and could prevent the bolt from tightening properly.
I know I usually add a little thread sealer to my bolts for peace of mind.

 

[04sleeper]

It is a good idea to replace the intake bolts as they corrode from the water passages and such like mentioned. I would get some ARP's, they are around $25 but well worth it IMHO.

Also, don't be afraid when laying down that front and rear bead on the block for the lower intake. Remember if you are using silicone to replace the gasket you need to make it thick so it squeezes out a little when you set the intake down. You want to set the intake down right away so it bonds to the intake and block, and be sure to clean the block and intake until they are shiny and then clean them with brake clean to make sure the silicone bonds.

Also 18-23 lbs. is all I have ever used. Not 25.

Good Luck.

 

[87AODGT]

the intake probably was not sitting down on the heads all the way when you were tightening,It may have looked like it but was just barely sitting up. I always use a rubber mallet to tap it down and make sure it is fully seated on the heads.

 

[Michael Yount]

Have the heads or the block been cut/milled?

 

[HardmanGT]

you also didn't put a thick enough bead of RTV on the ends. I made the same mistake when I assembled mine. Luckily, the engine was on a stand at the time and I was keeping an eye out for it while I tightened it down.

 

[pwcracer]

Well i went to the harware store and bought some grade 8 bolts, then I cleaned the old RTV off, and tried the process again. It worked this time! I still could have a leak, but everything torqued down properly, and I see some RTV come out of the front..

Here is a pic, how does this look? (I was told the heads were never milled)

http://home.comcast.net/~gbfan10/take.jpg

 

[Curse]

Looks like it sealed in the front. You might want to wipe/cut some of the silicone around where the distributor will sit, or setting down the distributor might be a problem. Good luck

 

[04sleeper]

Looks like it sealed in the front. You might want to wipe/cut some of the silicone around where the distributor will sit, or setting down the distributor might be a problem. Good luck

Also you might want to readjust that first rocker. Looks a little off. J/K

 

[5spd GT]

Yeah something could have been hindering the lower intake from wanting to go down (an obstruction).

A couple lower intake bolt partnumbers (though you already have them) are:

Lower Intake bolts – (hex) SUM-G1579HS
Lower intake bolts: arp-154-2001

Yep, trim a bit of that RTV around the distributor after it hardens...

 

[8950HO]

It`s a good idea to get 4 longer 5/16" bolts,cut the heads off,and use them as guide pins,so it lines up right the first time.