Can you assist with confirming where on the engine these parts lie ?
speed controller.jpg:This is a (heavy corroded) speedcontroller. It's similar to the one you can see in photos I have posted before, but the "torpedocoupling" has the part from the airtank connected, thus making it to appear a little different.
DSC_0012.jpg:This is the oil-distribution mechanism. It's mounted on the front cover of the engineblock and being run via a gear mounted on the engine's crankshaft (acting on the gear at the left in your photo).
It distributes "bursts" of oil to lubricate the different mechanisms in the torpedo (foremost the engine itself and the propeller-axle/crossdrive).
The vertical shaft on your photo is a link connecting to a rod driving the torpedo's distance-mechanism/"brake-mechanism". The "brake-mechanism" (in lack of a better english word...) keeps the torpedo's depthrudder locked downwards (typically at about 10 degrees) for the initial running distance (adjustable - typically 150-200m). When the engine-revolutions have turned this mechanism from the set distance to zero, a lever activates a rod lifting the hook locking the depthmechanism's servoengine, allowing the depthmechansim to function and control the rudder.
The distance-mechansim works in a similar way (but with a different gear, so it runs a lot slower): When it has moved down from the set distance (max 12000m), a lever will release the startinglever which again will shut off the main airsupply, as well as the supply of fuel, water and oil, making the engine stop and the torpedo slow down and seek to the surface.
On torpedoes equipped with a programsteering-device (ie Fat or Lut), there would also be a flexible axle connected to the left gear, transmitting the engine RPM's to the steeringdevice (to control the lenght of the straight legs and turns of the "zic-zac" running pattern).
DSC_0013.jpg:The part on the right I think must belong to the depthmechanism (the axl transferring the movement of the pendolum to the servoengine), but it's different than the ones from the TA I and II mechanisms used after 1942, so again: An early variant I think.
DSC_0017.jpg:This puzzles me (I'd like to see more photos from other sides, and measurements), but judging by all your photos, the parts comes from an early production torpedo, and there were several modifications from the first G7a(TI) version in 1925 to those being made later (and especially after 1940).
It might be an early variant of the seawater-pump (a simple gear-pump distributing seawater to the channels casted in the engineblock for cooling of the engine), but it's impossible to tell wihtout measurements and other photos.
DSC_0019.jpg:Again, this would be very useful to see from other angles and some measurements... (is it the same as DSC_0017.jpg??)
Obviously it's mounted in the hull probably in the gyroscope compartment or an exersice-head, but other than confirming it's from a very early produced torpedo I can't tell exacly what it is right now (might not be from a G7a at all).
DSC_0023.jpg:This is the hatch for the gyroscopecompartment. The iron ring on the front is an inlay of the hatch (which itself has been completely corroded), and the cross underneath is the part locking it in place (again: As this is made of brass, it's obvioulsy a very early produced torpedo).