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

Valve cover leak? Blue Puff?

  • Thread starter Thread starter Scott_B
  • Start date Start date Aug 23, 2004

Scott_B

"1 Arm Wonder! "
Founding Member
Oct 27, 1998
4,197
0
66
NS Canada!
Aug 23, 2004
#1
  • Aug 23, 2004
  • #1
Ok, i put on a set of Ford "mustang powered by Ford" valve covers. Thing is i have a few leaks. I used a cork gasket. But it obviously hasnt sealed very well. Also i noticed the sparkplugs have oil around the threads.

Anyways, when i hammer it, i get a short puff of oil out the tails. Could this be caused by oil getting through the sparkplug threads, or down between the headers and head, into the headers?

Its a rebuilt 302, .020 over. I seen it run in the car before i bought it, never smoked a bit!

So what do i do with the valve covres/ Torque em down more? Try rubber gaskets? Any ideas? will this do away with my puff?
 

pisgahhiker

New Member
Aug 6, 2004
148
0
0
Western North Carolina
Aug 23, 2004
#2
  • Aug 23, 2004
  • #2
valve guide seals

If theres anyway oil is getting between the heads, block,headers or spark plug holes you have big time problems exp on a new motor.

Did you have the heads rebuilt?

It could also be a fuel issue. I've seen alot of cars smoke when there not dialed in good.

Anyway all the things you listed Should be sealed or your going to be running like crap losing compression.(with the exception on the header to block)


If your heads were not redone and thats a fresh motor you should get a set done ASAP so they can break in with the motor.


As for the leaking covers find some of those MR gasket thick thick gaskets.
Usually most auto places have them near the chrome area.
If your lucky your parts store stocks parts for fords unlike the crap hole advance auto here thats hung up on SBC parts all ford stuff must be ordered.
 

Scott_B

"1 Arm Wonder! "
Founding Member
Oct 27, 1998
4,197
0
66
NS Canada!
Aug 23, 2004
#3
  • Aug 23, 2004
  • #3
Well, the motor has about 50k on it. I bought it used, but the guy is a friend. I had new vavle seals put in about 2 years ago.Wouldnt think theyd go that quick!

I thought about fuel, as its not tuened yet, but you can smell the oil, and can see the ble puff out the rear. Confirmed by two friends driving behind me.

I'll look for the other gaskets! Thanks!
 

Scott_B

"1 Arm Wonder! "
Founding Member
Oct 27, 1998
4,197
0
66
NS Canada!
Aug 24, 2004
#4
  • Aug 24, 2004
  • #4
Here is are a few pics of the leaks.



 
V

v8only

Active Member
Jul 3, 2003
2,378
22
49
Aug 24, 2004
#5
  • Aug 24, 2004
  • #5
Dont' waste your time on ANY other gaskets other than the ford replacement valve cover gaskets. They come on all newer 5.0's, maybe 90+?? Anyhow, they are a one piece metal gasket, with rubber on the edges. The gasket is firm as hell, and unbendable. You simply drop it down onto the head, and bolt your valve cover down. It's foolproof, and all but impossible to make leak, + they are reusable over and over again. Cost, maybe $30, but do the job right only once.
 

Scott_B

"1 Arm Wonder! "
Founding Member
Oct 27, 1998
4,197
0
66
NS Canada!
Aug 24, 2004
#6
  • Aug 24, 2004
  • #6
Thanks! But see what i mean, they almost look like theyre sponge and soaking up the oil and seeping it.
 

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
9,516
6
99
Arkansas
Aug 25, 2004
#7
  • Aug 25, 2004
  • #7
Yeah my valve cover gasket leaks...they are a cork gasket also...it is a very small leak but it bothers me...it probably didn't help that I made a hairline crack on both valve covers tightening it down...I should have just reused the stock ones...you don't have to position them to get the bolt holes through since they are firm compared to the very flexable cork ones...
 

mustangsquared

Founding Member
Jun 8, 2002
828
1
16
new bern nc
Aug 25, 2004
#8
  • Aug 25, 2004
  • #8
I blew a stock one a replaced it with the cork ones....leaking all over the place. Wont make that mistake twice..
 
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