Got a good look at the engine today. Here it is before teardown
First thing was to pull the head back off.
I will be replacing this head with a high compression head, which increases compression ratio from 4:1 up to 6:1. Back in the 20s, gas was of such poor quality that compression had to be reduced. Ford actually derated compression from 4.5:1 to 4:1 about 3 years into production because of the gas problem. With today's gas, 6:1 or even 8:1 compression ratios are possible. This gives a big increase in power, well above the 20 hp Model T's left the factory with.
Here is a look I had at the pistons before the engine was pulled
I was able to take a closer look at the pistons with the engine out, and they were rattling around in their bores. The rings were not compressed. Which explains the crappy compression I got before teardown. A new model T engine will generate about 50 psi compression. I was measuring around 12-15 psi. Part of that loss was due to the piston rings not sealing and part was due to leaky valves. The result was I was getting probably 10-12 hp out of my old engine.
Here is an old block that my buddy had laying around. Interesting that a spider crawled up the tailpipe, through the open exhaust valve, and fell into the combustion chamber forevermore.
Back to my engine, here you can see one of the cracks in the block, traveling from a valve seat to a cylinder
Now it was time to unbolt the auxiliary Warford transmission from the Ford transmission. Here is what the Warford looks like when installed in the truck.
These auxiliary transmissions were an aftermarket add-on, and provided both an under-drive and over-drive. And they are all cast iron and steel. Small, but weigh about 80 lbs.
With that done, the next job is to remove the upper transmission cover, called the hogshead.
Here is one of the transmission bands. The Model T has three bands, Reverse, Low and Brake. The wide drum is the brake drum, the middle is Low and the other end is reverse. Before 1926, all the drums were the same size. Ford increased the brake drum width in 1926 to provide better braking and to prevent the drum from cracking due to heat from braking. The reverse drum spins in the opposite direction than the other drums. When you push on the reverse pedal, the reverse band clamps around the reverse drum and you go backwards. When you press down on the low pedal, the band grabs the low drum and you move forward in low gear. Halfway up on the low pedal is neutral, which is like a typical standard transmission clutch pedal pushed all the way down. If you let up the Model T low pedal, the band releases the drum and you are now in high gear. High gear is direct drive in a Model T.
Then the oil pan comes off. The oil pan covers the bottom of both the engine and transmission. The transmission and engine share the same lubrication - 30 wt. oil. No tranny fluid in a Model T. These pans are held on with about a hundred bolts with castle nuts and cotter pins. Another weird thing about Model T oil pans is that the weight of the engine/transmission assembly causes the pan to bend over time. Happens so often that there is a special jig to re-straighten them.
Time to remove the valves, springs and cross pins. Here are the exhaust and intake valves
The valve stems are held in place by a cross pin, not keepers as are the design today. Here is an upside down pic showing the cross pins
Here are the valves removed
With the valves out, the next job is to pull the ford transmission
It takes a special wrench to access the 4 bolts holding the transmission to the engine
Here are pics of the trans coming off
Here is the magneto. It generates electricity to run the engine. I won't be reusing a magneto. I will run off the battery and generator.
Here is the engine block with the transmission removed
Next we will get into the bottom end