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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Head Plugs blowing out

  • Thread starter Thread starter 408lx
  • Start date Start date May 15, 2011
4

408lx

New Member
Apr 23, 2011
9
0
0
May 15, 2011
#1
  • May 15, 2011
  • #1
Anybody ever had any issues with head coolant caps blowing out? I have a 408w with a turbo setup and whenever i drove it hard the head frost plugs on my canfields would blow out, any ideas what would cause this.
 

stang-geoff

Member
Jan 2, 2010
69
1
6
May 15, 2011
#2
  • May 15, 2011
  • #2
wow, I've never heard of that happening before. I've heard of people blowing radiator hoses and heater hoses under large loads but never a plug. Interesting
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
May 15, 2011
#3
  • May 15, 2011
  • #3
you ahould have that much pressure in your coolant system, and if the motor and heads are flexing that is another issue.

Most head suppliers got away from the casting/freeze plugs. You can tap them and put threaded plugs in if you have enough meat.

What sealant are you using on the plug when you install new ones.
 
4

408lx

New Member
Apr 23, 2011
9
0
0
May 15, 2011
#4
  • May 15, 2011
  • #4
Pipe sealant, I sold the turbo kit off the motor now haven't drove it on the motor yet but I was thinking could the turbo system pressurized the coolant system? Everyone I talk to has no idea.
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
May 15, 2011
#5
  • May 15, 2011
  • #5
Use permatex #1
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
May 15, 2011
#6
  • May 15, 2011
  • #6
If the system was getting pressurized in many cases you have a head or intake lifting or a gasket blown
 
4

408lx

New Member
Apr 23, 2011
9
0
0
May 15, 2011
#7
  • May 15, 2011
  • #7
I was thinking of fabing some brackets to run across the plugs to stop them from popping out but would this damage something else like instead of blowing the caps, maybe blow a head gasket?
 

90fox306

New Member
Mar 20, 2011
126
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0
East TN
May 15, 2011
#8
  • May 15, 2011
  • #8
If theres that much pressure in the the cooling system, then if you fabbed a bracket to hold them in then if wud prob jus blow somthin else. Thats a wierd 1.
 
4

408lx

New Member
Apr 23, 2011
9
0
0
May 15, 2011
#9
  • May 15, 2011
  • #9
When I first put it all together I was testing and tuning the car and one of my lifters went along with blowing out a cap when the car was driven and parked back in my garage. I changed all the lifters and intake gasket along with a new mLs head gasket and on the 2nd attempt at tuning the car one of the caps blew out this time on the street, is this nuts or what?
 

90fox306

New Member
Mar 20, 2011
126
0
0
East TN
May 15, 2011
#10
  • May 15, 2011
  • #10
Yeah, thats pretty f***** up. Iv never heard of that. Sorry that I cant help you out.
 

Incon

Member
Jun 14, 2010
88
1
9
May 15, 2011
#11
  • May 15, 2011
  • #11
I had an old FE engine that did this, ended up being a crack in the head.
 
4

408lx

New Member
Apr 23, 2011
9
0
0
May 18, 2011
#12
  • May 18, 2011
  • #12
Really? If i did have a crack in the head wouldn't the motor overheat or run really hot?
 
4

408lx

New Member
Apr 23, 2011
9
0
0
Jun 12, 2011
#13
  • Jun 12, 2011
  • #13
??????
 
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