PT Boat Engine Room Walk-through Tour of Higgins PT658 in Portland OR

Well, here we are on PT 658 and many of you asked to take a

tour

of the

engine

room

, so we're going to go down into the

engine

room

and show you some of the key features of the world. only the engine room of the PT

boat

works, so I'm going to go down this vertical ladder to the engine room where there are three um 5 m 2500 cubic marine engines, they are v12 made by Packard Packard v12 and they burn aviation gasoline, for what we have the port, we have the starboard view made by the Packard exhaust hoses and then we have the mid engine with the two exhaust hoses coming out in either direction down here, just the general design that it has on the forward bulkhead, It has the engine control panel. with the engine order telegraphs right there, those pointers and then you have tachometer gauges for engine speed and you have manifold pressure gauges and you have Magneto selector switches here that have three positions, you have intake exhaust and on both uh for each of the three engines, you also have oil temperature, oil pressure and water temperature gauges here, these are all airplane style gauges, there is also a 7 day

boat

clock right there, you can see it and here on this half there's the tank level indicator so what you do is uh you have to have the two front 800 gallon tanks and the two rear 800 gallon tanks.

What you do is you have a little bit, which causes bubbles in the tank and you can see how much gas you have where the needle goes. a rough indicator, the most accurate way is to glue, put a stick in there, a graduated stick, um, here you can see the exhaust, uh, sorry, the fresh water expansion tank and it's a dry sump design, so which has an external lube boil sump tank that is there in the corner, it has about 20 gallons of oil in there, so it has a scavenge oil pump on the bottom and most of the oil is kept in that tank anyway, these engines are, uh 1,850 horsepower mainly due to the carburetor, supercharger and intercooler, so here's the carburetor, here's a holly 1685 f um, you can see where the gas goes in here on the side and, uh, that's a pretty big amount of gas, it uses 66 gallons. one hour when at cruising speed and then at top speed it burns 200 gallons per hour well no its closer to 170 gallons per hour so 500 gallons per hour for all three engines at top speed anyway so you can see the supercharger wheel that's inside This spiral type casing and then it sends the uh, it spins at 3,00 or 7,000 RPM when the engine crankshaft goes to 1,000, so it's driven by gears, then you have an intercooler and the intake manifold in the middle and then you have the exhaust manifolds. here and they are water cooled and they hold up well and they don't melt here you have the DC distribution board and you have the battery breakers right there is the battery box in each corner and then You have several loads and 24 volts DC up there and then you have ignition power and the lights, the 24 volt lights and down here is another one of those former oil sump tanks, here we have what's called an auxiliary generator. a capital that uses a wakaa motor and the control panel uses an old coal uh uh carbon washers uh type volt voltage regulator anyway so this actually works Although our 200 amp DC generator doesn't work because we don't have a arer vulture drag that works, uh um, the generator actually works, although if we could control it anyway, there's a workbench down here and a secret door to uh, after the part of the ship that's not in the original drawings and the exterior bulkhead we just replaced. bulkhead with new wood and then we are going to restore the voltage regulator that goes to the engine.

Each of these motors has a starter motor and a generator, so you can see the starter motor is the large one on the left, the generator is the smaller one on the right is a 40 amp 24 volt DC generator and it has a carbon pile, it's what's called a carbon pile voltage regulator right there and um, I think one works but the other one doesn't work because they're old, anyway, so something significant about these carbon tubes. exhaust is that they got very hot and were originally copper tubes that were inside a rubber hose with water flowing between them.

We didn't have that, so we just put uh uh. an accordion hose that was wrapped with fiberglass insulation and it melted the fiberglass and got so hot that flames were literally coming out of the back of the exhaust manifolds, so anyway we finally got some people and a couple of companies who donated their It's time and money to have stainless steel tubing that's bent and then we put it inside a rubber hose and there's a quarter inch piece of tubing spot welded in a spiral that goes all the way around and guides the water spiraled so that the outside of the thing only goes to 90° when it's running instead of 1 1800° which is what it was before, anyway, so you can see down here, we have the original vent fans, there it is supply vent up. oh no that's the exhaust and it just goes out into the engine room and then here you have the supply vent which is another fan and there's the control um you also have the shelf where they keep the engine manuals and We also have a sign in the engine room saying it is quite appropriate.

There's so much noise down here when these things are working that you don't even like it. I can shout in your ear and you can't hear, so we have this silence. Please come down. here, here, this is the control box for the other auxiliary generator that we're missing and it's supposed to be right there where that black toolbox is, but eventually, if we can find another auxiliary generator, we'll put it in there and uh. so we'll have everything we need, something inside these batteries, these battery boxes are basically 12 volt batteries connected in series and parallel, so we have 24 volts going to our starters.

An interesting feature on this DC distribution board is that these are the starters. solenoids, up there on the engine control panel you have a button that you start here, I'll show you and when you start the engine, you have to align the power, then you lift this little plate and you press the button and it starts, it makes the engine start and when you have enough oil pressure, you bring this to both and then the engine starts turning over as long as you have fuel, so anyway these solenoids, when you press that little button, you come here and you can go in.

In case the wire that connects that button to this solenoid trips or something and breaks, you can just press it and you'll turn the starter on that way, it's an electromagnet zone, it's cool, although you know, the Navy has it all. uh with a backup and this is the backup method to start the engines so let me see uh that's it um I hope you learn something and I'll try to take a movie next time we start right now uh so this is uh Jerry signing the only operational engine room on a real WWII PT boat uh PT 658