Are rubber valve cover gaskets JUNK? Pic inside

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,693
Reaction score
6,869
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
I’ll be the guy that will chime in and say that I really like the Fel Pro steel core rubber gaskets.

The biggest change for me though was getting away from using stamped tin/steel covers and going with more rigid cast aluminum covers- it is all I’ll use these days.
yes. the stamped steel will deform over too strong of a gasket. hell, torque the cork gasket enough on one corner and you basically guarantee a leak there too
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,693
Reaction score
6,869
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
You must be registered for see images attach

I proactively went back and put larger spreaders on to help mine. I just used stock cork which i had on my shelf for about as long as ive been alive lol... I think I cleaned it up real well and IIRC i used a gasket sealant to retain the cork in position on the head. But I could have just carefully staked it with the bolts and made sure it was positioned right too. The diffuiculty I have reaching makes me lean toward using gasket sealant.
 

SirRobyn0

Full Access Member
Joined
Dec 6, 2019
Posts
6,755
Reaction score
11,402
Location
In the woods in Western Washington
First Name
Rob
Truck Year
1984
Truck Model
C20
Engine Size
305
im just saying because of its use and properties, i wouldnt want that getting in my oil (like RTV in that sense) and if your gluing a rubber gasket to metal.. i feel at that point covers with strong construction and spreaders with a cork gasket will just work better lol
It's just a thin line of 3M weather strip adhesive, and like with RTV you don't want to slop it all over the place, but it's fine if used correctly and it does a VERY good job of holding gaskets in place and keeping them sealed on that side. The biggest down fall to me is it's a PITA to get it all off. What I like is having an air pump on my truck and all the associated lines it can be quite a trick to snake the valve covers in and out. So I can put a thin line of RTV (I like the right stuff in the caulking gun) right on the head. I can glue the cork gasket to the valve cover and if I bump or pressure the gasket against something snaking the cover back into place the gasket will stay in place no matter what. So for me it's a must do. But I think the main take away is we all have a different technique that works for us.
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,693
Reaction score
6,869
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
It's just a thin line of 3M weather strip adhesive, and like with RTV you don't want to slop it all over the place, but it's fine if used correctly and it does a VERY good job of holding gaskets in place and keeping them sealed on that side. The biggest down fall to me is it's a PITA to get it all off. What I like is having an air pump on my truck and all the associated lines it can be quite a trick to snake the valve covers in and out. So I can put a thin line of RTV (I like the right stuff in the caulking gun) right on the head. I can glue the cork gasket to the valve cover and if I bump or pressure the gasket against something snaking the cover back into place the gasket will stay in place no matter what. So for me it's a must do. But I think the main take away is we all have a different technique that works for us.
but they make gasket sealants for that purpose

You must be registered for see images attach
 

bucket

Super Moderator
Staff member
Super Moderator
Joined
Aug 3, 2010
Posts
30,439
Reaction score
28,345
Location
Usually not in Ohio
First Name
Andy
Truck Year
'77, '78, '79, '84, '88
Truck Model
K5 thru K30
Engine Size
350-454
I've seen a lot of guys use a lot of weatherstrip adhesive on gaskets, in all sorts of applications. It doesn't hurt anything at all if it's not used in excess.

I only use it to hold a stubborn gasket in place while I install it. Like the '87-up rubber valve cover gaskets that usually have to be stretched into the groove.
 

SirRobyn0

Full Access Member
Joined
Dec 6, 2019
Posts
6,755
Reaction score
11,402
Location
In the woods in Western Washington
First Name
Rob
Truck Year
1984
Truck Model
C20
Engine Size
305
but they make gasket sealants for that purpose

You must be registered for see images attach
Yes they do and what's the other one..... Gasgacinch... All great products I just can't tell much a difference between any of them other than 3M comes a in squeeze tube and those gasket sealants have a brush. I have used both and they all seem to work fine.
 

Nasty-LSX

TogetherforeverCovid19
Joined
Nov 22, 2014
Posts
1,395
Reaction score
1,737
Location
HOUSTON TX
First Name
Mi Hung Lo
Truck Year
85/86/87
Truck Model
c10/k10/k20
Engine Size
LSX
Ok, found the culprit after feeling DUMB for 2 days. After taking them off about 10
times and using silicone and no silicone I found the problem. My cheap $80.00
CHINA valve covers had to much material on the intake runner area. I took my
4in grinder and shaved off material just where the runners are touching the valve cover.
reinstalled and BINGO. Rubber gaskets with steel inserts or liners dont suck.
All is good now. I did not even use RTV o_O Take a look. I used grinder on
Valve cover not the intake. Took off lots of material. products just dont fit
correctly anymore. Pretty much just left a hair line lip. click on pic to blow it up BIGGER
up.

You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
 
Last edited:

HotWheelsBurban

Full Access Member
Joined
Mar 31, 2023
Posts
2,398
Reaction score
5,654
Location
Houston, Texas
First Name
Carol
Truck Year
1990
Truck Model
R2500 Suburban
Engine Size
350
I did something I told myself I was not going to do. Put Chrome valve covers on. I put a weiand stealth intake
on the truck and then said to hell with it and bought Chrome valve covers on it. I went to COMPETiTiON SALES
I bought all the rubbers and breather and gaskets. When I got home and opened the box, they were rubber. I
cannot get this crap to seal and stop leaking. Is the rubber junk? Do I need the thick cork type? I will say
engine looks ten times better and runs even better than before with this intake compared to stock.

You must be registered for see images attach
Competition Sales, didn't know they were still around! My dad used to buy stuff from them in the 60s and 70s. Still on the North Freeway?
 

Nasty-LSX

TogetherforeverCovid19
Joined
Nov 22, 2014
Posts
1,395
Reaction score
1,737
Location
HOUSTON TX
First Name
Mi Hung Lo
Truck Year
85/86/87
Truck Model
c10/k10/k20
Engine Size
LSX
Competition Sales, didn't know they were still around! My dad used to buy stuff from them in the 60s and 70s. Still on the North Freeway?
yes sir, also in Pasadena. Super shops is making a come back also :oops:
 

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,693
Reaction score
6,869
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
Ok, found the culprit after feeling DUMB for 2 days. After taking them off about 10
times and using silicone and no silicone I found the problem. My cheap $80.00
CHINA valve covers had to much material on the intake runner area. I took my
4in grinder and shaved off material just where the runners are touching the valve cover.
reinstalled and BINGO. Rubber gaskets with steel inserts or liners dont suck.
All is good now. I did not even use RTV o_O Take a look. I used grinder on
Valve cover not the intake. Took off lots of material. products just dont fit
correctly anymore. Pretty much just left a hair line lip. click on pic to blow it
up.

You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
that chinesium is gonna corrode out and die now
 

ChuckN

Full Access Member
Joined
Nov 8, 2022
Posts
1,316
Reaction score
3,996
Location
Bellinham, WA
First Name
Chad
Truck Year
1981
Truck Model
C10
Engine Size
350
Ok, found the culprit after feeling DUMB for 2 days. After taking them off about 10
times and using silicone and no silicone I found the problem. My cheap $80.00
CHINA valve covers had to much material on the intake runner area. I took my
4in grinder and shaved off material just where the runners are touching the valve cover.
reinstalled and BINGO. Rubber gaskets with steel inserts or liners dont suck.
All is good now. I did not even use RTV o_O Take a look. I used grinder on
Valve cover not the intake. Took off lots of material. products just dont fit
correctly anymore. Pretty much just left a hair line lip. click on pic to blow it up BIGGER
up.

You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
Nice work!

After you mentioned that, I got to thinking of my own and maybe I should check that out!
You must be registered for see images attach


After looking at mine with cast thicker valve covers, there’s lots of space in there- methinks perhaps your intake manifold has a lot of overlapping material in that area? No matter though- glad you found a solution!
 

Nasty-LSX

TogetherforeverCovid19
Joined
Nov 22, 2014
Posts
1,395
Reaction score
1,737
Location
HOUSTON TX
First Name
Mi Hung Lo
Truck Year
85/86/87
Truck Model
c10/k10/k20
Engine Size
LSX
Nice work!

After you mentioned that, I got to thinking of my own and maybe I should check that out!
You must be registered for see images attach


After looking at mine with cast thicker valve covers, there’s lots of space in there- methinks perhaps your intake manifold has a lot of overlapping material in that area? No matter though- glad you found a solution!
Yes the material on the intake runner area is pretty thick. I even tried the factory covers and they would
have needed to be modified also. Thats how I found out about to much material in the same area when the
factory covers were leaking also. Crazy!. You have plenty of clearance. Im glad I figured it out. I started
to believe the oil was coming from the intake bolt area or gaskets, but I knew it was all correct. Im glad I
tried to put the factory valves cover back on and when they leaked the same way I knew exactly what the
problem was at that point. :happy160:
 

stroker2

Junior Member
Joined
Oct 27, 2022
Posts
3
Reaction score
9
Location
Wisconsin
First Name
Jim
Truck Year
1986
Truck Model
C10
Engine Size
350
As a former NASCAR engine builder doing 450 plus engines a year , 3M weather strip adhesive was the preferred method to glue FelPro double cork metal reinforced gaskets to the covers . Never use RTV . Using the mention method you can remove covers ,set valves if needed and reinstall without leaking .Let the gasket do the sealing as designed . FYI our engine shop did R&D with FelPro to test new gasket designs. Thanks
 

Nasty-LSX

TogetherforeverCovid19
Joined
Nov 22, 2014
Posts
1,395
Reaction score
1,737
Location
HOUSTON TX
First Name
Mi Hung Lo
Truck Year
85/86/87
Truck Model
c10/k10/k20
Engine Size
LSX
As a former NASCAR engine builder doing 450 plus engines a year , 3M weather strip adhesive was the preferred method to glue FelPro double cork metal reinforced gaskets to the covers . Never use RTV . Using the mention method you can remove covers ,set valves if needed and reinstall without leaking .Let the gasket do the sealing as designed . FYI our engine shop did R&D with FelPro to test new gasket designs. Thanks
Ill look into that double cork gasket from FelPro. I do need a thicker gasket. Do you have a part #? Thanks
 

Latest posts

Forum statistics

Threads
44,163
Posts
950,684
Members
36,276
Latest member
2manysquares2care
Top