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Author Topic:   cylinder head help
posted July 21, 2004 07:12 PM
I have 351 windsor heads on my 347 and tonight I took my right side header off. When i went to put it on I went to clean the silicone out of a bolt hole and when I stuck my screw driver in the hole and started to pull the screw driver out......coolant started running out. upon examination a few others on the same side did the same......Im assuming this isnt normal. All of the holes have silicone in them from me over applying it when putting on headers( i use silicone instead of gaskets). I have never seen or noticed water leaking from these, even when I had the header off.....Help!!!! Whats wrong? Car is running fine....has good power.

posted July 21, 2004 08:02 PM
all windsor header bolt holes that i've seen are blind, meaning they don't go into the water jacket. that being said, someone could've had to drill out a broken bolt at some point and went through to the water jacket. i'd use a little thread sealer on them and call it good.

posted July 22, 2004 08:11 AM
i am guessing all the silicon in the bolt holes cracked the head when you tightened the bolts seal up the bolts and use them anyway just my 2 cents

posted July 22, 2004 04:14 PM
What kind of silicone do you use. Is it a high temp like the orange stuff.

posted July 29, 2004 11:02 PM
hey everyone a lesson in hydraulics.when using silicone be VERY careful NOT to get it in the bolt holes.Like 21racer said you can crack a head or even a block.I saw a guy actually crack the block on a D6 cat a couple yrs.ago because the bonehead put silicone on the head bolts!!It's great stuff when used properly but can cause a lot of grief if misused.


posted July 31, 2004 07:02 AM
I agree with the silicone hydraulic theory why? because ive been there.I have cracked a couple tranny cases on chrysler front drives trying to push the silicone out of the holes.lesson learned clean the hole out and be careful with silicone.As outlaw said you should be able to seal it with some sealer

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