Upper and lower intake manifold gasket

[localhorst]

Hello, I'm replacing the seals on the upper and lower intake manifolds. That's a well-known problem. The cooling water became less and less and it smoked white from the exhaust pipe.

Since my intake manifold shows some traces of the seal, I would like to know whether it would be sensible to replace it at the same time? How do you assess the condition (see photo) of the intake manifold? I am concerned that water or oil can run under the seal and cause damage again.

 

[Alan 55]

Hello, I'm replacing the seals on the upper and lower intake manifolds. That's a well-known problem. The cooling water became less and less and it smoked white from the exhaust pipe.

Since my intake manifold shows some traces of the seal, I would like to know whether it would be sensible to replace it at the same time? How do you assess the condition (see photo) of the intake manifold? I am concerned that water or oil can run under the seal and cause damage again.



Welcome to the forum. From the pictures I see nothing out of the ordinary. When the surfaces are cleaned up you can examine them again to be sure. When cleaning it is very important to prevent particles from falling into the intake ports and other critical areas. I use red shop rags for this purpose. Some may oppose this idea stating that lint could come off of the cloth and cause contamination. If this is of concern it may be possible to use duct tape to seal the ports. In any case, keeping things clean is needed.View attachment 29328

View attachment 29326

 

[BuickGirlFromMars]

Using negative pressure like a vacuum around the port as you work could help for debris. Lint would be much less damaging in an engine than abrasive material especially metal. I saw a video where a small amount was left in an engine and it caused the equivalent wear as about 150k miles(on a relatively normal wear trend) to the main bearings and other surfaces before it finally circulated to the oil filter that could cause oil pressure to go from something to nothing on an engine with mileage. That could half the service life of the engine and realistically probably worse than half for an owner in reality

 

[HotZ28]

If you have any deformation (cavity's) of the head surface, or LIM surface, you can fill them with JBweld and smooth the surface with a putty knife before the bond takes place. Then let it set/cure for 24-hrs before reassembly!

 

[localhorst]

Thanks for your help, I will clean it up and then reassemble. Have ordered the seals from FelPro metal, the current ones were plastic. Maybe the metal ones will last better and longer.

I would clean the surfaces with a rag and brake cleaner. I don't know if there are any better ways. The oil which was in the cavities under the intake manifold, I have sucked and cleaned. In the upper intake manifold, which is made of plastic, it also smelled like gasoline, maybe I would have to change the fuel injection pressure regulator.

Sorry for my bad English, I hope you can understand it.

 

[Alan 55]

Thanks for your help, I will clean it up and then reassemble. Have ordered the seals from FelPro metal, the current ones were plastic. Maybe the metal ones will last better and longer.

I would clean the surfaces with a rag and brake cleaner. I don't know if there are any better ways. The oil which was in the cavities under the intake manifold, I have sucked and cleaned. In the upper intake manifold, which is made of plastic, it also smelled like gasoline, maybe I would have to change the fuel injection pressure regulator.

Sorry for my bad English, I hope you can understand it.

In order to clean the surfaces, it may require something slightly abrasive such as some light emery cloth. This is where it is necessary to be careful to avoid getting any foreign matter into the ports. The fuel pressure regulator can be tested once the engine is running. When the vacuum line is removed from the regulator, there should be no gasoline present.

 

[localhorst]

I took some sanding fleece to clean it. That worked quite well. I also found a small crater on a cylinder head next to the passage for the coolant. It could be the problem with the oil in the water. You can feel it when you run your fingernail over it. I plugged all the inlets before grinding.