I'm interested in getting a model T in the next year or so. In preparation I've been studying all the drawings and document I can get a hold of. One thing I don't understand is how the crank bearings and the cam bearings get lubricated. I see there is an oil tube coming off the top of the fly wheel. Does this somehow run oil through a channel that lubes these bearings?
It is a splash only system.
Mostly splash. The oil is thrown around and is collected in various places where it can drip down through holes to oil the bearings. There are also dippers where the oil accumulates and is picked up by the rods. Neat huh? Mike
Robert -- The oil tube carries oil to the front of the crankcase. The oil then works its way back to the sump at the flywheel. On its way there, it is splashed and dripped all over everything in between.
Cyclonic oiling. KGB
So is it the rods that splash oil on the crank bearings? I get that the rods dip into the oil but obviously the cam and crank bearings can't do that.
You've got it!
Robert, The flywheel and magnets are running in the oil at the bottom of the crankcase at the transmission area. The oil is violently thrown about inside the rear of the crankcase. There is a small funnel just in front of the flywheel that collects oil. With the car level that funnel/tube runs downhill to the front of the engine at the cam gear location. The oil then travels back to the rear of the engine passing thru the dips on the bottom of the inspection cover on the bottom of the crankcase. The rods "dip" into this oil splashing it around and lubricating the mains, rods, pistons, and cam shaft. The main bearing journals of the block have small holes for the oil to run into the main bearings. The lifters and valve chamber on the side of the engine get oil from the "mist" created by the "splashing" of the rods. All of this is dependent on the car being somewhat level most of the time. If climbing a steep hill for very long you can starve the front of the engine for oil, because the oil tube/funnel is now sloping uphill instead of downhill. I have heard that the old saying "protect old number one" is referring to the front main and number one rod of the T engine. To illustrate how violent the oil is being thrown around inside the crankcase. I had left off the starter bendix cover. I accidently started the engine. In the time it took to get from the front of the car to the key and kill the engine, all 5 quarts of the engine oil were forceablly ejected thru the bendix cover hole ... There is a lot of oiling going on inside the engine, just remember "to protect old number one"
These cutaway pictures may help.
I've got to agree with Donnie, I think that the term splash is way too mild, deluge, is closer to the truth. I was adjusting the bands one day, and with the inspection cover off, I accidentally hit the starter button. Oil came gushing out at an unbelievable rate. I was mopping up oil for an hour.
Awesome. Thanks! So specifically the main bearings receive oil that the block collects from the splash and runs down a journal slot.
Is it fair to say that these bearings then ride on a film of oil as modern plan bearings do? Or is it more that enough oil is moving around that it just transfers heat from the bearing? I know the babbits melt at around 400F so I'm assuming the bearings stay comfortably below that.
I have a great interest in the engineering and design of the model T as you can tell.
Robert,yes it is fair to say that these bearings then ride on a film of oil as modern plan bearings do. A little more info on how it works.
Thanks Frank! That's actually pretty amazing. That's pretty ingenious. I wonder how far back this technique goes. I suspect it was probably used in steam engines prior, but that's just a guess.
Do you have a lawn mower or other piece of equipment with a small four stroke engine?
They also use the splash system.
1959 Briggs and Stratton from a Toro Sportlawn reel mower.
How far will those boards get on a tank of gas?
It doesn't go anywhere on the grass, but when I put it on the concrete driveway, it vibrates along its merry way, like the players of your old electric football game.
It's a cute and very clean motor and runs great. I currently have it listed Craigslist. Lots of inquiries but no cash, yet...
I'd think that Mack Cole would want that.