Cooling Water Fitting Sealant?

Not yet? Fuel pump and fuel filters as planed will all be inline on the hose. (https://www.holley.com/products/fue... HOC Memorial Day Sale Fuel Systems Highlight) I agree with the concept of buying a complete marinized engine package, but I've researched this idea for eight plus years and I would like to think the path I'm going down will still work just fine. The biggest reason is the buy-able engine packages will not fit in my boat's engine bay and $$. The base engine was purchased as a brand new marinized GM version of the 6.2 LS. In all applications that I've seen the exhaust manifold are being used as the exit point of the heated sea water. I'm very open to be educated as to why this would not work? For the fuel injection intake manifold I'm looking at using Performance Design unit. (https://shop.performancedesign.com/xs-ls3-intake-manifold-p29.aspx} I have a height of the FI manifold issue that this unit fixes and will look good with the hatch open. A special marine flame arrest type air filter will be used on the throttle body. With respect to mix / match, Do you mean on the sea water intake system? If so, the recommendation to minimize the effects of galvanic reaction was to go with SS fittings were possible. This boat most likely will be a trailer queen most of the time. Just short 6 hours in the fresh water runs. If you are referring to the engine and drive train? Again I'm wide open to learning about what works the best or why what I'm looking at doing will not work? Your thoughts are greatly appreciated. Thank You! Bob

 

Bob what Gonzo is saying about manifolds has always been the case with fresh water cooled marine engines in my experience.

Sea water is injected after the manifold generally via a component called an "exhaust elbow", which are often misnamed "risers". The coolant circulates through the manifold but the elbow is cooled by sea water exiting the heat exchanger.

Best approach is probably to ask the manufacturer.

 

Good Morning all that are following this thread! Chev Gen III LS1 Manifolds https://www.cassellmarine.com.au/products/chev-gen-iii-ls1-manifolds?_pos=107&_sid=a68c47040&_ss=r These are the maifold's link. I guess it's too early in the AM for me. I'm having a bit of brain lock. Bob

 

That is an automotive system that is dangerous and illegal on a boat. Marine systems are self contained and no pressurized hoses are the cheap rubber type like the Holley you show.

As for aluminum exhaust manifolds being raw water cooled, they will corrode in a relatively short time. They are performance items that are not designed for a long life, but to be as light as possible. Unless you are going to race, there will be no appreciable difference between you project and an off-the-shelf unit.

 

Interesting! I'm glad for the details. Now I can further check into these systems and have good questions. This style of exhaust manifold is the only thing that would fit in the engine bay. I think I'll have to take my chances with them.