Antifreeze leak coming from header flange

FrnkNsteen · Feb 28, 2018

Ok,.... Strange question....

I was replacing my leaking back up light switch on the 833 transmission in my '67 barracuda last night. I was reinstalling the inspection cover that I removed to clean where the leaking lube got between it and the trans, when I brushed across the pass side header collector flange and noticed it was wet.

I had been noticing a small puddle of antifreeze here and there, but only if it sat for a while. I started looking and it seems to be coming from the back right corner of the head, and actually looks like it is coming from the header flange to the head. I immediately started thinking "Great,... I've got a bad head gasket or something", but something occurred to me this morning.

Do the exhaust bolts go into the water passage on 906 heads? I swear that years ago I remember antifreeze coming out of some of the bolt holes when I was changing header gaskets on the 440 in my Charger. Seems to me we put a little high temp RTV on the bolts when we put them back in.

Is it possible I have a loose header bolt and antifreeze is slowly seeping out when it sits for a while? I will have to take a look at it tonight and see if the header bolts are tight.

moparedtn · Feb 28, 2018

Yep, the header bolts/studs are in water jackets.
Yep, put some sealant on the threads when bolting the header up.

Bill Monk · Feb 28, 2018

Yes, and I use #2 permatex sealant on the bolts. U will need to drain at least the radiator, that should get the coolant level in the block below the bolt hole.

FrnkNsteen · Feb 28, 2018

Thanks guys. I will try to take a look at it tonight.

Thanks again!!

lewtot184 · Feb 28, 2018

this is why I use studs and not bolts.

FrnkNsteen · Feb 28, 2018

lewtot184 said:
this is why I use studs and not bolts.

I would agree, but the header is so close to the inner fender on that car, I don't know that I could get it over the stud. Suppose I could insert the studs after the header is in place, but seems like that would be a pain too.

Bill Monk · Feb 28, 2018

FrnkNsteen said:
I would agree, but the header is so close to the inner fender on that car, I don't know that I could get it over the stud. Suppose I could insert the studs after the header is in place, but seems like that would be a pain too.

I've run into that with headers too

PurpleBeeper · Feb 28, 2018

FrnkNsteen said:
I would agree, but the header is so close to the inner fender on that car, I don't know that I could get it over the stud. Suppose I could insert the studs after the header is in place, but seems like that would be a pain too.

I have made a compromise due to this problem. I currently run studs BUT, I have about 1/2" cut off of each one AND I have header bolts on the ends of both heads. I cut off the studs years ago having trouble putting on headers. I ran a few nuts on the studs (to protect them) & hacksawed the ends of the studs of, then unbolted the nuts to true up the threads. A better idea would have been to use a die.

I just ordered a set of studs for my new "street-only" motor. I will be running aluminum heads & I'm afraid of stripping them running steel header bolts in/out. I plan to cut down the studs & glue them in the heads & run nuts on the studs, similar to my current motor, but all studs (if clearance allows).

FrnkNsteen · Feb 28, 2018

Well,... I got home a little early and had a chance to take a look at it quick. There are studs in most of the holes and a bolt second from the back. Everything is tight. Could it still be leaking from there even if it's tight?

oldbee · Feb 28, 2018

Sure can.

Sublime70rt · Feb 28, 2018

I had this same exact problem, but in my case the hole got stripped out from trying to fit up hooker super comps 100 times. I could not get a bolt to seal, it had to be a stud because they are tapered where they meet the head. I tried teflon tape, teflon paste, high temp rtv, I even called permatex they told me what sealer to use and, none of it worked. I called a friend who pretty much builds most of big blocks in my area, and he said use jb weld. I was very hesitant at first but,after attempting to seal the stud 5 times I was ready to just buy edelbrock heads. I put jb weld on it 2 years later not a drop, and if you ever need to remove it just heat it up make sure to clean hole and stud with brake clean and let jb weld set for two days thats what I did good luck

FrnkNsteen · Mar 1, 2018

Sublime70rt said:
I had this same exact problem, but in my case the hole got stripped out from trying to fit up hooker super comps 100 times. I could not get a bolt to seal, it had to be a stud because they are tapered where they meet the head. I tried teflon tape, teflon paste, high temp rtv, I even called permatex they told me what sealer to use and, none of it worked. I called a friend who pretty much builds most of big blocks in my area, and he said use jb weld. I was very hesitant at first but,after attempting to seal the stud 5 times I was ready to just buy edelbrock heads. I put jb weld on it 2 years later not a drop, and if you ever need to remove it just heat it up make sure to clean hole and stud with brake clean and let jb weld set for two days thats what I did good luck

Hmmm,.... Would have never thought of that. I guess with a stud, there isn't a need to remove it often. Thanks!

Antifreeze leak coming from header flange

FrnkNsteen

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moparedtn

I got your Staff Member riiiight heeeere...

Bill Monk

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FrnkNsteen

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lewtot184

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FrnkNsteen

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Bill Monk

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PurpleBeeper

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FrnkNsteen

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oldbee

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Sublime70rt

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FrnkNsteen

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