exhaust manifolds PCM 5.7

[laurie8888]

This may be a stupid question, however which ports does the water flow through the manifold.

I drained exhaust manifold, removed Riser for inspection and there is one large hole in center partially internally corroded, I guess water flows through this into the matching exhaust manifold large hole.
Then also there are 4 thin slots on either side of manifold and riser, presume these are for gases and should have black carbon inside instead of rust....and should not fill with water ....Am i right?

[AirTool]

The water is on the outside....else the surface of the manifold would be EXTREMELY hot. When the gaskets leak...they leave a rust trail down the outside.

Plus a lot more cross sectional area is needed for the exhaust than the water.

Also note one end of the outside has your water hose and the other end has a drain plug.

http://www.submarineboat.com/images/..._lost_foam.jpg

[laurie8888]

Thanks Airtool thats what I thought

However when I sprayed some water into the Drain hole on the outside of the exhaust manifold im pretty sure some water shot up through the large hole in the middle....am i missing something here? how could this happen if they are seperate chambers

[AirTool]

That doesn't sound good.

[laurie8888]

After this I replaced the Riser gasket and put back together

I have started the engine a few times and revved up to 3500 RPM, No problems encountered, also oil is normal viscocity on touch and no visual discoloration> temp 162 max.


I only sparayed water in where water was coming out (drain holes)

Manifolds are only 12 mths old. maybe I was seeing things!

[AirTool]

Manifolds are only 12 mths old. maybe I was seeing things!

Probably so.