• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

freeze/core plug replacement IN CAR! need some help

  • Thread starter Thread starter Foxfan88
  • Start date Start date Apr 8, 2008

Foxfan88

My Grandpa has great wood.
Sep 13, 2004
2,487
4
0
Miami, Ok
Apr 8, 2008
#1
  • Apr 8, 2008
  • #1
ok i got my car running this past weekend and everything runs great but my freeze plugs are rotting through and starting to leak.

originally started as one, but after driving the car and having the engine running and the heay cycles, more of them started.
i tried to rig it up using JB waterweld putty, and just the pressure of my finger when applying the putty managed to break up the rush and cause it to start pouring out, the plugs are just plum rusted though. a few of them are, a few arent leaking but i will replace them anyways.

last year i had too much water and not enough antifreeze, plus the car sat for months like that. so i am sure that didnt help.

there are only 6 plugs on the block, none in back so thats good.

just checking in to see anyone has done this job. seems like a PITA, from what i can tell, i'm going to have to remove the starter, unbolt the engine mounts and jack the engine up and totally remove the mounts. then hammer out the old plugs (probably hardest part)
and then buy an epxanding plug, i am told there are some made of brass or copper, that use an acorn nut to expand it out.

anyone got any tips or advice that could save me some time and headaches, because i am really dreading this. hopefully i can keep working it up as a huge PITA and then when i actually do it, it wont be so bad lol.

just sucks though, got the engine running, runs great, got my tweecer in the mail and this comes and bites me in the butt. oh well. i am glad its just a simple leak and nothing wrong with the engine.
 

Roland69

Sergeant Tangnet
Sep 17, 2005
2,867
2
58
Port Elgin, Ontario
Apr 8, 2008
#2
  • Apr 8, 2008
  • #2
don't use one of them expanding plugs please.... if the hole is 1 5/8 buy some 1 5/8 plugs (just an example may be different size than that) getting the old one out is the PITA like you said but the new one goes in alot easier. Make sure the hole in the block is clean maby sand it a little if you need to. Find a socket (I was using one of my impact sockets) that fits inside of the new frost plugs almost tightly. hammer it in the block carefully making sure the plug stays strait and pound it in just past where it is flush....like a finger nail in past flush.
 

Foxfan88

My Grandpa has great wood.
Sep 13, 2004
2,487
4
0
Miami, Ok
Apr 9, 2008
#3
  • Apr 9, 2008
  • #3
yeah i would do that for sure but the problem is going to be not enough room to get anything in there to hit with it, and not a straight shot to hit it evenly. i wont know how bad it will be until i tear it down. i will pull the plugs out and measure and go from there.
 

88stangmangt

Active Member
Nov 25, 2003
2,332
1
48
Stafford,VA
Apr 9, 2008
#4
  • Apr 9, 2008
  • #4
might as well pull the motor you have a plug on the back of each head and one on the backside of the block infront of the flywheel/flexplate....but if you decide to skimp on those plugs they make a angled tool with different size disks on a ball and socket end to install plugs in the car...have no idea where to buy one as mine is old as dirt...

If it was me i would unbolt the motor wounts and dropp the tranny x-memeber undo the exhaust and pull her out..1 day job.
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
Apr 10, 2008
#5
  • Apr 10, 2008
  • #5
On a stock engine block there are only 6 core plugs/freeze plugs that have water against them, 3 on each side. The large plug in the rear of the motor is the cam plug.

The plus are 1.50" and I would use the deep Pioneer Brass plugs, use Permatex #1 on the seating surface and the plug and tap them in straight past the radiused edge of the block. This will be a PIA in the car but I guess it could possibly be done with a lot of time and paitence....I'd pull the motor.
 

Foxfan88

My Grandpa has great wood.
Sep 13, 2004
2,487
4
0
Miami, Ok
Apr 10, 2008
#6
  • Apr 10, 2008
  • #6
yeah i only have the six on the sides of the block. the one on the back is only holding oil and my heads are aftermarket and dont have any plugs on them.
 
You must log in or register to reply here.

Similar threads

B
Engine Another no start after washing engine bay
  • bruno
  • Apr 26, 2026
  • Fox 5.0 Mustang Tech
  • 2
Replies
24
Views
586
Fox 5.0 Mustang Tech May 7, 2026
AeroCoupe
B
Electrical Why does my fox body keep frying eecs
  • brandyn200
  • Jun 20, 2026
  • Fox 5.0 Mustang Tech
Replies
8
Views
198
Fox 5.0 Mustang Tech Jun 25, 2026
AeroCoupe
J
can you use the heads off a H O 302 to put on a regular 302 engine
  • Jan H
  • Feb 25, 2026
  • Other Auto Tech
Replies
6
Views
334
Other Auto Tech May 17, 2026
nickyb
D
Engine 85 GT Backfires through Carb
  • DienstXIV
  • Oct 3, 2025
  • Fox 5.0 Mustang Tech
Replies
19
Views
632
Fox 5.0 Mustang Tech Oct 7, 2025
85GTStangGuy
K
Resolved Need some assistance. Holley Terminator X alongside H/C/I. Very rough/inconsistent idle
  • karhoot
  • Jun 6, 2026
  • Fox 5.0 Mustang Tech
Replies
0
Views
79
Fox 5.0 Mustang Tech Jun 6, 2026
karhoot
K
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?