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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech

Engine Afr Head Studs Leaking.

  • Thread starter Thread starter RIO5.0
  • Start date Start date Jul 29, 2012

RIO5.0

15 Year Member
Feb 16, 2001
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Jul 29, 2012
#1
  • Jul 29, 2012
  • #1
Anyone got a fix?? I read around its not uncommon for these to do that. I just started my new 331 and seen the leaks after it came up to temp. I was thinking it was the rear of the intake as I had that the last time cause I used the gaskets.
I let the car cool down and re-started and than noticed little bubbling around the nuts...I was like W.T.F.??? I always seen little drips of anti freeze on the block few years back and never knew why... I do now.

I ran ARP thread sealer as usual... on the bottom of the studs...never even thought to goop up the threads up top. I should have run bolts instead of the freakin things... Never had leaks and chit like this with them...

I hate the thought of tearing it apart to fix some piss azz leaks... %^&$#@
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
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#2
  • Jul 29, 2012
  • #2
You have to gob on the Ptfe pretty hard on the bottom of the stud. You don't put the thread sealer on the nut. If coolant is getting up to the top of the stud, it's already gotten where it shouldn't be. Use arp moly lube on the nut to get proper torkage.

Kurt
 

RIO5.0

15 Year Member
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#3
  • Jul 29, 2012
  • #3
Thanks Kurt.... Ticks me off as I cleaned the studs good and put the ARP sealer right to em. Only after seeing the bubbles I thought. you bonehead... you didn't goop up the top...I knew it didn't make sense....I was just looking for a reason. Only (1) has a pretty good drip. Damn discouraging after all the work.
I did lube up the nuts prior to TQing em.
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
Jun 14, 2004
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Jul 29, 2012
#4
  • Jul 29, 2012
  • #4
I haven't ever used the ARP thread sealant, so I don't know whether or not it's a good product. I always use the Permetex brand from the Autoparts store. I have never had that stuff leak on me.

Kurt
 

BlownFiveLiter

have car, will race....wait, it doesn't run
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Jul 29, 2012
#5
  • Jul 29, 2012
  • #5
I used plain old Permatex blue on my studs, but I have both seen and heard of using RTV on the threads. I would imagine that would do a fine job of stopping any leaks.
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
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Jul 30, 2012
#6
  • Jul 30, 2012
  • #6
You're definately not suposed to use rtv on the studs. Every manual I have ever seen specifically says thread sealant. The white stuff with ptfe in it.

Kurt
 

BlownFiveLiter

have car, will race....wait, it doesn't run
15 Year Member
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#7
  • Jul 30, 2012
  • #7
I wouldn't think so, but the person I've seen talk about it here was Rick 91GT. A buddy of mine used it on his, at the recommendation of the machine shop that built his shortblock. I haven't used it, so I can't comment to its success rate. PTFE is oil soluble, so I would think it could eventually break down and leak, at least in theory. I'm definitely no chemist, or engineer though, so I would go with whatever is recommended by the manufacturer of the studs, or the engine builder.
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
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Jul 30, 2012
#8
  • Jul 30, 2012
  • #8
There shouldn't be any oil in the water jacket. Rtv works, it just leaves a mess to clean up next time you take the studs out. All that has to be cleaned out for a fresh seal the next time around. The liquid teflon never fully hardens, so when you run a tap down there, it sticks to the tap and comes out. The rtv will harden into chunks of rubber which no matter how much you blow out the block with air are going to end up in the coolong system when you clean the threads. All that crap eventually ends up in your radiator and clogs it. I have spoken to Arp on the phone several times and they have been very specific on this everytime, bringing it up on each phone call whether I ask or not. I think Rtv is just a very popular mechanic tool, and has become a fix all.

Kurt
 

Rick 91GT

Mustang Master
Nov 29, 1999
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Jul 30, 2012
#9
  • Jul 30, 2012
  • #9
After having issues with a few sets of studs and bolts with arp teflon sealant years back I called ARP tech. I was advised to use permatex ultra black on the threads with no issues to the tq spec they provide.

The issue lies in the sharpness in the threads of the ARP bolts compares to the stock block which I always run thread chasers and brushes through. I was also advises to lightly sand the threads to knock off the sharp edge if needed.

No issues since... I do use the ARP ultra tq lube on all nuts washers and surfaces.
 

RIO5.0

15 Year Member
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Jul 31, 2012
#10
  • Jul 31, 2012
  • #10
Well after about 75 miles or so the leaking has kinda subsided... Had one the was leaking pretty decent and that seems to have stopped... I'll take it as I wasn't all the horny to dive back into pulling it apart.

On a side note since I have you guys attention. After bringing it to full temp I let it cool down then pulled the spout and set the timing. The things seems to like 22 deg or at least that were I left it to start. I tried dropping it back some and it was kinda doing the lean pop thing as I went lower. Bringing it high seems to take that away. Does 22 seems excessive? I don't appear to get any rattling or detonation either. she pulls nice with no breaking up or the like.

I had to throw the old 331 block away due to the bores being .008 - .010 tapered when the shop tore it down for balancing. So i got a seasoned block and a full balancing / rebuild from a local shop... Its nice a smooth now... quite a difference when you have the full monty balancing done.
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
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#11
  • Aug 1, 2012
  • #11
Yeah, 22 base timing is way too much. Should be no more than 16.

Kurt
 

95Vert383AOD

15 Year Member
Jun 10, 2008
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Aug 1, 2012
#12
  • Aug 1, 2012
  • #12
Question...

Can RTV be added to a stud without pulling the head gasket off?

Can the stud in the water jacket be removed RTV'ed and retorqued???

I have expensive O-Ring gaskets i would like to not disturb if at all possible.

I have the 12 point head studs and have has coolant disappear. Compression test was fine and nothing in the oil. Its been like this a while.

Chris
 

Rick 91GT

Mustang Master
Nov 29, 1999
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Aug 2, 2012
#13
  • Aug 2, 2012
  • #13
yes you can do one stud at a time, you need to drain the water so it is below that level on the block. If you have used antifreeze it is a little more tricky since you need to get the threads clean enough so the rtv will seal, brake clean on a small thread cleaning brush usually works.
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
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Aug 2, 2012
#14
  • Aug 2, 2012
  • #14
.... and a bore cleaning rod and brush in .45 ACP for the holes.
 

95Vert383AOD

15 Year Member
Jun 10, 2008
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Aug 2, 2012
#15
  • Aug 2, 2012
  • #15
Rick 91GT said:
yes you can do one stud at a time, you need to drain the water so it is below that level on the block. If you have used antifreeze it is a little more tricky since you need to get the threads clean enough so the rtv will seal, brake clean on a small thread cleaning brush usually works.
Click to expand...

Would i need to re-torque all the head bolts or can i just do each lower bolt 1 at a time in a random sequence?
 

Rick 91GT

Mustang Master
Nov 29, 1999
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Aug 3, 2012
#16
  • Aug 3, 2012
  • #16
1 at a time start at the edges work your way to center
 

VibrantRedGT

"STANGNET'S PENGUIN SMACKER"
15 Year Member
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Aug 10, 2012
#17
  • Aug 10, 2012
  • #17
RTV on threads? Man it took me like 4 hours to clean intake threads they were so caked with RTV. One of the worse days ever.
 

95Vert383AOD

15 Year Member
Jun 10, 2008
1,133
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69
New Bedford, MA
Aug 10, 2012
#18
  • Aug 10, 2012
  • #18
VibrantRedGT said:
RTV on threads? Man it took me like 4 hours to clean intake threads they were so caked with RTV. One of the worse days ever.
Click to expand...

Yeah i saw that theres some Permatex high temp thread sealer. Realistically it shouldnt take much RTV or sealer either way. Just enough to sit in the bolt threads. But i'll be using The thread sealer.
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
Jun 14, 2004
9,289
1,632
214
Acworth, GA
Aug 11, 2012
#19
  • Aug 11, 2012
  • #19
VibrantRedGT said:
RTV on threads? Man it took me like 4 hours to clean intake threads they were so caked with RTV. One of the worse days ever.
Click to expand...

Bingo. Been there and done that.

Kurt
 
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