sbc rear intake manifold oil leaks - Page 2

Hacksaw · 09-17-2024, 09:31 AM

Mike: after you clean the manifold, do a dry fit to check how much gap you have. Don't assume it's near OEM tolerences. You may need to lay an extra thick bead.

cad · 09-17-2024, 11:12 AM

If you are using the rear oil pressure port by the distributor, ensure the fitting is not cracked. I chased a leak for quite a while, and then whola, it broke in my hand while reaching behind to feel for the leak.

Dirk Olson · 09-18-2024, 01:46 PM

Ultra grey or black will not leak,both will cure in oil, sob to clean off but works. been using for years. Also works great for gasket substitution for timing chain, water pump, fuel pump cover, 4sd covers and tailstock etc.

ZenzenRacing · 09-18-2024, 02:40 PM

I'll second what Dirk said, good stuff!

Run to Rund · 09-18-2024, 08:50 PM

I have had great results with Permatex ultra black. Clean the surfaces with lacquer thinner, use a thick enough bead, etc. as others posted.

Signman · 09-19-2024, 10:08 AM

With all due respect
My limited engine bolting experience have found Right Stuff is awesome seals great is expensive, Ultra works great does the same job is lower cost.
The difference is Right Stuff cures quickly when you need to get the engine running now, Ultra takes a while to cure you have to have some time to let it set up.

Both are great products.

If the china wall or back of intake have been milled for port alignment you will need to apply a high amount of either product to seal. Make sure the distributor opening is clear when it squishes a finger swipe may be required.

DanBar · 09-19-2024, 07:29 PM

In the past I have had problems with this area when the head gasket was a little short of reaching the edge of the cylinder head at the 3 point junction of the china wall cyl. head and the intake manifold. When applying sealant it would not push into the gap left by the slightly short [.020-.040] head gasket by itself. It would leave a gap the thickness of the head gasket under the head at that junction point of the 3 surfaces. Since then I make sure to put a dab of rtv on the inside of the block and using a finger make sure there is sealant forced into that spot before applying rtv to the china wall for the manifold. hope this helps. Dan

09-17-2024, 09:31 AM	#11
Hacksaw Senior Member Join Date: Sep 2016 Posts: 857 Likes: 163 Liked 286 Times in 159 Posts	Re: sbc rear intake manifold oil leaks Mike: after you clean the manifold, do a dry fit to check how much gap you have. Don't assume it's near OEM tolerences. You may need to lay an extra thick bead.

09-17-2024, 11:12 AM	#12
cad Senior Member Join Date: Apr 2009 Location: Omaha, NE Posts: 683 Likes: 156 Liked 78 Times in 44 Posts	Re: sbc rear intake manifold oil leaks If you are using the rear oil pressure port by the distributor, ensure the fitting is not cracked. I chased a leak for quite a while, and then whola, it broke in my hand while reaching behind to feel for the leak.

09-18-2024, 01:46 PM	#13
Dirk Olson Member Join Date: Mar 2003 Posts: 182 Likes: 32 Liked 149 Times in 38 Posts	Re: sbc rear intake manifold oil leaks Ultra grey or black will not leak,both will cure in oil, sob to clean off but works. been using for years. Also works great for gasket substitution for timing chain, water pump, fuel pump cover, 4sd covers and tailstock etc. __________________ Dirk Olson 5036 STK

09-18-2024, 02:40 PM	#14
ZenzenRacing Member Join Date: Aug 2005 Posts: 257 Likes: 227 Liked 42 Times in 16 Posts	Re: sbc rear intake manifold oil leaks I'll second what Dirk said, good stuff!

09-18-2024, 08:50 PM	#15
Run to Rund Senior Member Join Date: Sep 2007 Location: Henderson, NV Posts: 578 Likes: 7 Liked 47 Times in 25 Posts	Re: sbc rear intake manifold oil leaks I have had great results with Permatex ultra black. Clean the surfaces with lacquer thinner, use a thick enough bead, etc. as others posted.

09-19-2024, 10:08 AM	#16
Signman Senior Member Join Date: Oct 2003 Location: Lower Slower Delaware Posts: 511 Likes: 15 Liked 226 Times in 85 Posts	Re: sbc rear intake manifold oil leaks With all due respect My limited engine bolting experience have found Right Stuff is awesome seals great is expensive, Ultra works great does the same job is lower cost. The difference is Right Stuff cures quickly when you need to get the engine running now, Ultra takes a while to cure you have to have some time to let it set up. Both are great products. If the china wall or back of intake have been milled for port alignment you will need to apply a high amount of either product to seal. Make sure the distributor opening is clear when it squishes a finger swipe may be required. __________________ Frank Ferrucci I/SA 1271 "Be Thankful for the Gifts You are Given"

09-19-2024, 07:29 PM	#17
DanBar Junior Member Join Date: Jan 2022 Location: summer shade ,ky Posts: 15 Likes: 21 Liked 9 Times in 4 Posts	Re: sbc rear intake manifold oil leaks In the past I have had problems with this area when the head gasket was a little short of reaching the edge of the cylinder head at the 3 point junction of the china wall cyl. head and the intake manifold. When applying sealant it would not push into the gap left by the slightly short [.020-.040] head gasket by itself. It would leave a gap the thickness of the head gasket under the head at that junction point of the 3 surfaces. Since then I make sure to put a dab of rtv on the inside of the block and using a finger make sure there is sealant forced into that spot before applying rtv to the china wall for the manifold. hope this helps. Dan