txaggie
Full Access Member
- Joined
- Apr 1, 2024
- Posts
- 112
- Reaction score
- 146
- Location
- austin texas
- First Name
- kris
- Truck Year
- 1985
- Truck Model
- suburban C20
- Engine Size
- 454
454 engine rebuild and intake gasket leak
- Thread starter txaggie
- Start date
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.
txaggie
Full Access Member
- Joined
- Apr 1, 2024
- Posts
- 112
- Reaction score
- 146
- Location
- austin texas
- First Name
- kris
- Truck Year
- 1985
- Truck Model
- suburban C20
- Engine Size
- 454
Went with this as a replacement order today:
www.summitracing.com
Fel-Pro 1212 S-3 Fel-Pro Performance Intake Manifold Gasket Sets | Summit Racing
Free Shipping - Fel-Pro Performance Intake Manifold Gasket Sets with qualifying orders of $109. Shop Intake Manifold Gaskets at Summit Racing.
- Joined
- Aug 3, 2010
- Posts
- 30,424
- Reaction score
- 28,257
- Location
- Usually not in Ohio
- First Name
- Andy
- Truck Year
- '77, '78, '79, '84, '88
- Truck Model
- K5 thru K30
- Engine Size
- 350-454
Typically with used heads and/or intake, it's best to smear a very thin coating of rtv around the coolant ports, to prevent minor leaks like that.
txaggie
Full Access Member
- Joined
- Apr 1, 2024
- Posts
- 112
- Reaction score
- 146
- Location
- austin texas
- First Name
- kris
- Truck Year
- 1985
- Truck Model
- suburban C20
- Engine Size
- 454
the heads were cleaned and machined, all new gaskets everywhere, and a new edelbrock air gap intake. I’m about to go retorque everything because we haven’t checked that post heat cycles. Wonder if that could be it?
txaggie
Full Access Member
- Joined
- Apr 1, 2024
- Posts
- 112
- Reaction score
- 146
- Location
- austin texas
- First Name
- kris
- Truck Year
- 1985
- Truck Model
- suburban C20
- Engine Size
- 454
Bolts were really loose. Some were down to only 5 foot pounds when spec is 25. Hopefully it solves it.
- Joined
- Aug 3, 2010
- Posts
- 30,424
- Reaction score
- 28,257
- Location
- Usually not in Ohio
- First Name
- Andy
- Truck Year
- '77, '78, '79, '84, '88
- Truck Model
- K5 thru K30
- Engine Size
- 350-454
Hopefully the intake face of the heads were not machined as that can make it more likely for the intake to have fitment issues.
hogdaddy
Full Access Member
- Joined
- Jan 12, 2023
- Posts
- 127
- Reaction score
- 237
- Location
- Alabama
- First Name
- mike
- Truck Year
- 1986
- Truck Model
- Scottsdale
- Engine Size
- 350
Edelbrock and many others recommends a non-steel core gasket for use with aluminum intakes as the low torque of the bolts does not sufficiently compress the steel core gasket.
Last edited:
75gmck25
Full Access Member
- Joined
- Oct 13, 2016
- Posts
- 2,254
- Reaction score
- 2,193
- Location
- Northern Virginia
- First Name
- Bruce
- Truck Year
- 1975
- Truck Model
- K25 Camper Special TH350 NP203
- Engine Size
- 5.7
I also found that the old bolts for my stock intake on an SBC were just a little too long for the thinner flange on the intake. I'm not sure how the BBC compares.
Some of the SBC bolts (center?) go through the head into the valley, so no issue other than making sure they have RTV to stop oil weeping. However, IIRC the four end bolts on the SBC are into a blind hole, and if the bolt is too long it may bottom out and give you a false torque reading before it completely compresses the intake gasket. In my case it was the bolts nearest the firewall that led to a small loss of antifreeze, which finally turned into a stream.
Some of the SBC bolts (center?) go through the head into the valley, so no issue other than making sure they have RTV to stop oil weeping. However, IIRC the four end bolts on the SBC are into a blind hole, and if the bolt is too long it may bottom out and give you a false torque reading before it completely compresses the intake gasket. In my case it was the bolts nearest the firewall that led to a small loss of antifreeze, which finally turned into a stream.
