Exhaust manifold Warehouse
The plan is replace the Ford 7.3's current cast-iron exhaust manifolds with a water cooled aluminum manifolds. (1) Marine fatigue manifolds such as the one in to image on a Detroit diesel are cardboard boxes built all over exhaust pipes coming right from the cylinder head. They notably reduce steadily the exhaust temperature, the motor storage space heat and reduce steadily the motor heat up time. (2) Marine manufacturers like Glen-L carry damp manifolds for Chevy and Ford machines generally converted for utilized in jet ships. Among the list of suppliers given just below I found MesaMarine which could custom build the manifolds but i will be too afraid to ask just what that will cost. Manifold Warehouse had them, nonetheless they cost about $2000 when it comes to set.
How To Not Ever Build A Damp Manifold
I began by-doing some evaluating with lost wax casting then switched to lost foam. (1) (2) missing foam is an ongoing process in which you initially produce the component you prefer in styrofoam. Afterward you encase the foam a shell of dirt which baked into a hard ceramic like crust. Eventually you afin de in molten aluminum that burns out of the foam and fills the void. Allow it cool off, knock off the shell of dirt, clean it, and you're done. The method were unsuccessful miserably for me personally, however it was an excellent education. You'll find out more about it here: "Lost Foam Casting".
How to Build A Wet Manifold
The theory now's to bend, reduce, and weld a damp manifold collectively. Harbor Freight put their particular pipeline benders on sale once again thus I now have a 12 great deal pipeline bender and I made a few practice bends. (1) Preheating the pipe may be the trick to flexing aluminum, otherwise it tears open as soon as you reach greater than a 20 degree change. The pipeline in reduced part of the photo tore available whenever forced to bend without adequate heat. Also hot is together with pipeline melts with very little caution because unlike metallic, aluminum does not turn red before it melts.
(2) Each manifold is made from 1 3/4 inches pipelines welded to a 1/2 dish that bolts on fatigue head. The pipes immediately direct the flow downward. About six ins from the head the four pipes merge into two pipelines, that carry on down in parallel after that turn 90 degrees toward the rear where they will certainly join collectively. I tried to help keep the turns mild and maintain just as much volume within the pipe as you are able to to be able to reduce steadily the drag and pressure.
At underneath end associated with the exhaust, the pipes link into a cast aluminum adapter with pipe tread for a 3 inch metal check device. (3) To throw the adapter, a straightforward aluminum mildew ended up being fashioned from scrap aluminum together with check valve. A plate in the end of a brief little bit of pipe ended up being placed to the check and this held the passage open and only allowed the aluminum to throw the threads of the check device. Covered the component plus the device threads with a layer of soot allowed the pipe to be removed while the cast component unthreaded through the check valve.
The check valve will avoid water from flowing back up in to the exhaust once the motorboat is submerged. Sea-water floods in through exhaust ports is something to-be prevented together with check valves tend to be an added degree of protection to avoid this from taking place. If everything works perfectly they may not be required. The motor storage space is paid with background air, but there is absolutely no way for the background pressure easily attain the exhaust side of the motor since the exhaust side is shut from the the valves and piston bands so the check valves ensure that water wont rise through exhaust. To help keep the check valves cool, the raw water-supply through the jet pump may be piped in and injected in to the check valves so that it is directed onto the valve gate. The natural liquid will also further cool off the fatigue before it passes through a flexible fatigue pipe that connects the check device to an excellent aluminum exhaust pipeline with exits the transom underneath the water-line.
(4) Ken "Welderman" who's among my welding and casting sources have been after could work and so I sent him the image of my manifold in which he reacted so it appeared as if I'd pin holes which I should pressure test that. I thought it seemed very good, but I sealed within the manifold, connected it to a 12 volt tire pump, brushed on some soapy water, and... maybe you have observed those types of bubble devices? A number of the holes had been easy to fix but other individuals had been persistent. I could grind the weld out, fill it back and the leak will be right back. We burned through and patched a couple of spots thus I had been sometimes working backwards. After 16 hours of path and mistake I finally got the holes patched so the pump achieved 40 psi before too-much air was leading out the short-term seal between your face plated. The most effective approach would be to lay out parallel welds, and use my stainless brush to get rid of the soot between each pass. The pin holes most often had been at the end of the welds, thus I began operating your final weld across most of the stops, or hooking the termination of the weld so it crossed throughout the previous weld.
(5) The next step was to weld on bolt passages. These are make from 1 inch rod and drilled with a 7/16 gap that will allow a 3/8 inch bolt to feed providing the manifold a small amount of area for thermal development. Each passage had been positioned after which spot welded onto the 1/2 face dish. (6) there clearly was no way to go across the exhaust pipelines so 7/8 inches holes were drilled thought the face plate to revealed the bottom end of each passage way. The union for the passage way additionally the face dish had been then welded from within the hole, plus the hole ended up being full of a couple of extra passes. Eventually the 7/16 opening for the bolt had been drilled down once more.
(7) (8) The exhaust pipes after that tend to be enclosed by flat sheets in order to develop a liquid package. Engine coolant liquid will flow into each manifold towards the top front after which be directed past all the fatigue ports before flowing down the manifold where it's going to be connected with a flexible coolant hose heat exchanger build in to the hull. The flexible coolant hose and versatile fatigue hose will allow the engine to maneuver because vibration and tork without damaging the manifold.
Using the liquid field completed we pressure tested the box and when once more worked hours to correct the pin holes. Desiring a significantly better answer, we looked to the magic of chemistry and purchased a gallon of CPS-128 Seal All Polymer Sealer from directions for use tend to be: "simply pour Seal-All™ into the water-jacket. Wait one hour, or apply 10 PSI for 1 minute to penetrate the leak. Pour excess out and shop inside initial bottle to recycle. Treat for one hour at 200°F or 8 hours at 72°F." It was that simple also. I'll use Seal-All in every of components that hold pressure as well as the speed-up equipment box.