Author Topic: Valve Cover Leak?  (Read 2026 times)

Offline Simple

  • Jr. Member
  • **
  • Posts: 52
Valve Cover Leak?
« on: September 16, 2015 - 05:47:01 PM »
Anyone have trouble with their valve cover gaskets leaking? I have tried the expensive blue "rubber" gaskets as well as the cork gaskets. Keep getting leaks in both sides. New fresh motor with new valve covers. Still leaks 😡




Offline 734406pk

  • Andy
  • Sr. Member
  • ****
  • Posts: 1716
Re: Valve Cover Leak?
« Reply #1 on: September 16, 2015 - 06:21:42 PM »
Do you have stamped steel or cast aluminum covers?
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive

Offline tman

  • Sr. Member
  • ****
  • Posts: 1331
Re: Valve Cover Leak?
« Reply #2 on: September 16, 2015 - 07:11:53 PM »
Where exactly are they leaking?  at the lower corners? 

Offline cudabob496

  • Sr. Resident
  • ******
  • Posts: 8024
Re: Valve Cover Leak?
« Reply #3 on: September 16, 2015 - 07:46:09 PM »
search this site under "valve cover leakage" and there will be lots of info
72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.

1999 Trans Am, LS1, heads, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"

2011 Kawasaki Z1000

Offline dougs bs23

  • Sr. Member
  • ****
  • Posts: 1691
Re: Valve Cover Leak?
« Reply #4 on: September 16, 2015 - 09:42:19 PM »
With the new gaskets get yourself a new set of bolts. The old ones may be stretched and not torquing properly


Sent from my iPhone using Tapatalk
see Bill run  go Navy football///fly navy

Offline YO7_A66

  • Jr. Member
  • **
  • Posts: 160
Re: Valve Cover Leak?
« Reply #5 on: September 16, 2015 - 09:58:41 PM »
 I had a leak on my stock steel 340 valve covers. I pulled them off to find that the bolts/washers had ripped the metal open around a couple of the mounting holes. After some J/B Weld, they are solid again. I also ordered the thick grey gaskets with the steel inserts. I applied some sealant to the valve cover side and torqued down the valve covers. I also bought the bolt set that has the WIDE washers. I have not had any more leaks.

Offline 734406pk

  • Andy
  • Sr. Member
  • ****
  • Posts: 1716
Re: Valve Cover Leak?
« Reply #6 on: September 16, 2015 - 10:29:55 PM »
I had a leak on my stock steel 340 valve covers. I pulled them off to find that the bolts/washers had ripped the metal open around a couple of the mounting holes. After some J/B Weld, they are solid again. I also ordered the thick grey gaskets with the steel inserts. I applied some sealant to the valve cover side and torqued down the valve covers. I also bought the bolt set that has the WIDE washers. I have not had any more leaks.

Very common issue! Good fix! :2thumbs:
1973 Challenger 440 6 pack auto 3.91 rear
2012 Dodge Ram 3500 dually 6.7 Cummins Fleece EFI Live
1973 Challenger 318 2bbl auto 2.73 rear 22.5 mpg RIP
1970 Challenger TA 340 4bbl auto-Sold and sad
1999 Dodge Ram 3500 dually 5.9 Cummins Fleece tuned VGT-sold
1995 Kawasaki ZX1100E & still alive

Offline Racer57

  • Sr. Member
  • ****
  • Posts: 1489
Re: Valve Cover Leak?
« Reply #7 on: September 16, 2015 - 11:30:19 PM »
Cast aluminum valve covers.......

Tried all types then bought the Moroso Perm-Align gaskets with the steel core. Since I have no plans or reason to ever take the covers off again I also used Black Permatex on both sides of the gaskets after wiping everything down with Prep-All. No leaks


Offline cudabob496

  • Sr. Resident
  • ******
  • Posts: 8024
Re: Valve Cover Leak?
« Reply #8 on: September 17, 2015 - 01:29:38 AM »
With the new gaskets get yourself a new set of bolts. The old ones may be stretched and not torquing properly


Sent from my iPhone using Tapatalk

and use new lockwashers under the bolt heads
72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.

1999 Trans Am, LS1, heads, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"

2011 Kawasaki Z1000

Offline Racer57

  • Sr. Member
  • ****
  • Posts: 1489
Re: Valve Cover Leak?
« Reply #9 on: September 17, 2015 - 08:52:52 AM »
While their off, it would be a good idea to get a thread tap and clean the threads out.