Tips and Tricks to installing new exhaust components on your boat.
This guide will help both new and experienced boaters when it comes time to replace those aging exhaust components, usually rusted or clogged by years of water exposure. Please note that this guide does assume you have a basic knowledge of tools and are able to use them properly (including torque wrenches).
Cleaning and Preparations
• Remove paint from gasket surfaces on your new parts using a razor blade and lacquer thinner. A gasket scrapper can also be used, but be careful to not damage or mar the surfaces. Then use compressed air to thoroughly blow debris out of exhaust passages and water jackets.
• Note that depending on the casting method, many new manifolds and risers come with bits of casting pieces left in their water jackets. This is not a sign of a defective part, it is just part of the casting process. It is a good idea to blow these pieces out prior to installing.
• Make sure the gasket surfaces on your head(s) are also clean, and scrape as necessary (be careful not to get debris down the ports).
• If reusing bolts, water fittings, or other parts, make sure they are clean of rust and in reusable condition. It is usually not a good idea to reuse lock washers, especially if they show any signs of corrosion, so replace those as necessary.
• Never reuse gaskets, they should always be replaced. If purchasing a part from me, examine the picture and description in the listing to see if the part comes with a gasket or not. If it does not, contact me and I can supply them.
With all of your parts clean and ready to install, follow these steps and don't forget to torque down all bolts/nuts to the correct torque setting. Overtightened bolts can lead to threads getting stripped, cast parts cracking, or bolts breaking, and can void any warranty that the part carried.
• Manifold-to-head gaskets should be installed dry; do not use any gasket sealer, silicon, or other compounds.
• Riser and Elbow gaskets may require sealer depending on the type of gasket. Most gaskets purchased from me will not; however, thin gray paper gaskets will require a Permatex non-hardening sealant.
• Do not use anti-seize or lubricants on the threads of bolts or studs unless instructed to do so.
• Do not use stainless steel or grade 2 bolts except for in specific applications, they are generally too soft and will not hold a torque setting.
• When installing studs, use a red thread locking compound on the threads that will seat in the casting (not on the nut end).
• Follow your original manufacturer's service manual for specific torque settings when installing manifolds, risers, or elbows. If you do not have it, contact an original equipment dealer in your area (look up your engine manufacturer's website for a list of dealers). 35 or 40 ft-lbs is generally a safe setting for 3/8" grade-8 course-thread bolts. Be sure to torque evenly and in steps.
• Torque should be reset after initial startup, while the parts are still warm.
• When installing pipe fittings or plugs, do not over-tighten them. They need only be snug. And avoid using thread sealant tapes or compounds which contain Teflon.
Now that your new parts are installed and properly torqued, insure that all hose clamps and hoses are also connected and tight. Look over the bilge and engine to make sure you did not leave any tools or parts laying around.
I hope this guide has been a help. Contact me with any questions. Thank you.