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351 2v Weiand 7516 Intake Blowing Front And Rear Gaskets

  • Thread starter Thread starter Walter Sparks
  • Start date Start date Jun 24, 2013
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Walter Sparks

Member
Jun 22, 2013
38
0
7
Savannah Georgia
Jun 24, 2013
#1
  • Jun 24, 2013
  • #1
I purchased this car with a rear blown intake gasket. I replaced the gaskets and now my front and rear gaskets are blown out. Any idea why or how to stop it? I do not think that I am getting engine blow by.
 

horseballz

10 Year Member
Sep 30, 2009
824
19
49
Las Vegas, NV
Jun 25, 2013
#2
  • Jun 25, 2013
  • #2
In what manner is your PCV system setup/laid out? PCV=Positive Crankcase Ventilation
Gene
 

iskwezm

10 Year Member
May 24, 2005
4,159
20
79
Rowland Heights,California
Jun 25, 2013
#3
  • Jun 25, 2013
  • #3
I never use those gaskets.they move and get squeezed out. Use thick bead of RTV instead.
 

Walter Sparks

Member
Jun 22, 2013
38
0
7
Savannah Georgia
Jun 25, 2013
#4
  • Jun 25, 2013
  • #4
I was kinda thinking to use a thick bead of black RVT gasket maker. I kinda thought that seal looked like a bad idea.
 

Walter Sparks

Member
Jun 22, 2013
38
0
7
Savannah Georgia
Jun 25, 2013
#5
  • Jun 25, 2013
  • #5
I will check the PCV set up today.
 

Walter Sparks

Member
Jun 22, 2013
38
0
7
Savannah Georgia
Jun 25, 2013
#6
  • Jun 25, 2013
  • #6
Ok my pcv valve has a hose going to my carb. I took some pics. The other valve cover has a oil cap that just snaps in place, it comes out pretty easy and I would assume if there were excessive crank case pressure it would just pop off. I blew through the pcv valve to make sure it is not clogged. I noticed that the hose going to the carb is slightly flattened where it bends.
 

horseballz

10 Year Member
Sep 30, 2009
824
19
49
Las Vegas, NV
Jun 25, 2013
#7
  • Jun 25, 2013
  • #7
The pics beg the question: Did the front and rear manifold gaskets blow outwards or did they move/get sucked inwards? The crankcase is, for purposes of this discussion, a sealed system and includes not only the crankcase, per se, but all areas where oil flows and returns to the pan, IE, oil pan, valve covers, galley under the intake, timing cover, etc. The job of the PCV valve and hose that is plumbed to your carb is to provide suction/vacuum to the crankcase system to relieve and evacuate pressure in the crankcase from blow by (even the freshest, tightest engine will have at least a little blow by) evaporating oil, etc. The filler cap on your driver side valve cover needs to be a filtered vent to allow clean fresh air into the crankcase to replace the air sucked out by the PCV. Picture what happens when you suck on a straw and then put your finger over the open end. If you suck hard enough the straw will collapse. The unvented cap is basically your finger over the end of the straw. All that said, I agree that properly applied beads of black RTV are a vast improvement over those damned end gaskets, however, your PCV system needs to be addressed also.
HTH,
Gene
 

Walter Sparks

Member
Jun 22, 2013
38
0
7
Savannah Georgia
Jun 25, 2013
#8
  • Jun 25, 2013
  • #8
they were blown outwards. I will try to find a vented oil cap.
 

blown65

Founding Member
Jul 7, 1999
1,938
4
39
Queen Creek Arizona
Jun 25, 2013
#9
  • Jun 25, 2013
  • #9
Right Stuff Gasket maker, in a tube not the can deal. Will not blow those out. My intake gasket let go at 20psi boost and I had about that in the crankcase and didnt blow the end seals out. Hell, I could hardly get the intake off. lol

My intake was not flat btw is why the gasket didnt survive. However the ends held up fine.
 

horse sence

15 Year Member
Nov 29, 1999
12,264
8,114
233
Wile Coyote's stunt double
Jun 25, 2013
#10
  • Jun 25, 2013
  • #10
i never use the end gaskets , you can not keep them in or from leaking.a silicone bead will not blow out. the driver side oil cap is origonaly vented also by a hose going into the bottom of the air cleaner. the carb. also vents the crank case ,as the butterflys open creating vacume it relieves the crank pressure. rember the pistons are not only building pressure /compression
on the way up but also to an extent on the way down as well, so atleast a vented oil cap would help. a pcv valve pulses so it is not as great a crank evacuation system on its own as it would be with a vented oil cap.
 

Walter Sparks

Member
Jun 22, 2013
38
0
7
Savannah Georgia
Jun 26, 2013
#11
  • Jun 26, 2013
  • #11
OK I have been shopping new intake gaskets and I have noticed that many do not have the hole in the center for the water port, and others have some differences on the ends also. Also some do not come with the metal valley pan. Can anyone give me some guidance here with all of these differences but the gaskets say they are for the same engine.

part numbers are

Mr. Gasket Standard Intake Gasket Sets 214

MS96012 Fel pro

Fel-Pro Performance Intake Manifold Gasket Sets 1240


in order


 

clement

Founding Member
Feb 27, 2001
1,106
52
59
Oak Cliff
Jun 26, 2013
#12
  • Jun 26, 2013
  • #12
if you aren't running breathers or the pcv is plugged that can blow out gaskets.
 

Walter Sparks

Member
Jun 22, 2013
38
0
7
Savannah Georgia
Jun 26, 2013
#13
  • Jun 26, 2013
  • #13
PCV valve is not clogged. I will be getting a vented oil cap.
 

horseballz

10 Year Member
Sep 30, 2009
824
19
49
Las Vegas, NV
Jun 26, 2013
#14
  • Jun 26, 2013
  • #14
Not sure about the issue for or against the valley pan. I think you will find that the center hole is not for coolant, but rather an exhaust crossover to help cold start drivability and warm up. Some engines benefit from this more than others, for example, FE engines are known to be cold blooded pigs until fully warmed up when this passage is plugged or non-existent! In warmer climates it usually is not a necessity. Many/most after market intakes do not have this crossover and even if they cast the hole, it often just goes to a short, blind, dead end. I'm not well experienced with Clevelands, but I am certainly aware that for the Windsor engines, not all intake gaskets are created equal. I'll leave it to some of the Cleveland "experts" here to recommend the best gasket set for you.
HTH,
Gene
 

Walter Sparks

Member
Jun 22, 2013
38
0
7
Savannah Georgia
Jun 26, 2013
#15
  • Jun 26, 2013
  • #15
Well I am in Savannah GA area so it is never really cold and mostly HOT HOT HOT. I dont think it will be a biggie to plug those holes then.
 

Hack

15 Year Member
Mar 23, 2004
1,945
13
69
Minneapolis
Jun 27, 2013
#16
  • Jun 27, 2013
  • #16
The valley pan prevents oil from coking on the underside of the intake. Some people run them, some don't. They can be more of a pain to seal than not having a valley pan, from what I've heard. Some people even cut the areas that seal onto the heads off the valley pan and run a partial pan just with the ends that rest on the block. I did this. I drilled a hole to allow oil to drain if some gets around the edges and into the pan.

The last 400 I put together I left the whole valley pan in and it sealed up fine. If you follow the directions you shouldn't have too much trouble.
 

Walter Sparks

Member
Jun 22, 2013
38
0
7
Savannah Georgia
Jun 27, 2013
#17
  • Jun 27, 2013
  • #17
Thanks...I will see what happens....
 

horse sence

15 Year Member
Nov 29, 1999
12,264
8,114
233
Wile Coyote's stunt double
Jun 27, 2013
#18
  • Jun 27, 2013
  • #18
i usualy leave that pan out. if your intake doesn not have the heat cross over passage the bottom of the intake should not get as hot as one that goes through . if it does you can plug it off.
 

Walter Sparks

Member
Jun 22, 2013
38
0
7
Savannah Georgia
Jun 28, 2013
#19
  • Jun 28, 2013
  • #19
The new gasket does not have the exhaust crossover hole. So I will just leave the pan out or cut the ends off where the seals keep blowing out.
 

horse sence

15 Year Member
Nov 29, 1999
12,264
8,114
233
Wile Coyote's stunt double
Jun 28, 2013
#20
  • Jun 28, 2013
  • #20
is it blowing any oil at the timing cover seal or rear main? just wondering.
 
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