Timing a Model T

Tom in SW VA

Tom in SW VA

Well-known member
I have a simple (stupid) question. How do you set the timing on a Model T? I am a Model A person and this my first foray into the Universal Car. I have a 24 T.

Thanking you in advance :)
 
Could someone give me step by step instructions on timing a Model T?

From locate TDC on cylinder one on .................

Thanks a million!:)
 
Pull No 1 spark plug. With key off crank the engine till you feel compression with your finger over the hole. Look in the hole and watch the piston come up to TDC, both valves should be closed. Go a smidge past TDC till the piston is just over center going down. If you look at the pin in the crank shaft it should be just past 3 and 9 oclock. Disconnect the rod from the timer. With the timing/spark lever up, turn on the key to battery. If the coil is buzzing, turn the timer counter clock wise till the buzzing stops then turn clock wise till if just starts. Now bend to adjust the rod till it goes in the hole in the timer. Unless there is a short in the system, there is only battery voltage at the timer. Unless there is a lot of wear or slop in the linkage this will put you really close in the ball park.
Should add; if the coil is not buzzing try turning clockwise till it just start to.
 
Last edited:
1. Pull out the #1 spark plug
2. Shine a light in the spark plug hole (flashlight)
3. Using the hand crank watch in the hole as you crank the engine. You are looking for the compression stroke where both valves are closed and the piston is coming upwards.
4. To determine the exact place the spark should happen use a plastic stir stick from McDonalds or a plastic straw. Place the straw on the piston as it approaches TDC on the compression stroke. You will feel the piston come to the top. The crank handle will move an inch or so with no movement of the piston, because the piston is "at" TDC.
5. Continue to gently turn the engine using the crank. When the piston just begins to move downward stop! This is where the spark needs to happen.
6. Lay the #1 spark plug on the head bolt with its wire connected.
7. Disconnect the timer rod from the steering column.
8. Turn the ignition on "BAT".
9. Adjust the timer until it the spark happens just after the piston passes TDC as in steps 1 - 5. You can repeat steps 1 - 5 with the key on to verify that you have indeed found the right spot.
10. Bend the timer rod so that the timer is in this position with the rod connected and the spark lever on the steering column is all the way up.
 
I use an hourglass when timing a model t.

Them sucker are slow.
 
Last edited:
Two people have given instructions on how to time a Model T. Does yours have a distributor? If so you need to let us know and what kind. When someone ask how to time a Model T the default is coil and timer.
If it's an original Bosch, there are a couple of different style Bosch units that are each setup a little different.
 
Then if you are having a problem than we need more information. Just moving it back to the top does not help you.
Both way shown above get to the same place with slight differences in approaches.
 
It is hard to see sometimes down into #1 cylinder to find the best spot just past TDC. I take a 1/4 in. dowel (about 15 in. long) and put in down on top of the #1 piston and lean the dowel on the radiator support rod. You can then make a pencil mark on the dowel next to the support rod when you are just about at TDC. Now you have a nice indicator of where the #1 piston is located with respect to TDC.
 
That what the pin in the crankshaft pulley is for. When it's horizontal the engine is at top dead center (3:00) at about 3:15 it just past TDC.
 
That's why I always use a plastic straw. It is easier to feel it go past TDC than it is to see it, and more accurate too.


Ed in Maine said:
It is hard to see sometimes down into #1 cylinder to find the best spot just past TDC. I take a 1/4 in. dowel (about 15 in. long) and put in down on top of the #1 piston and lean the dowel on the radiator support rod. You can then make a pencil mark on the dowel next to the support rod when you are just about at TDC. Now you have a nice indicator of where the #1 piston is located with respect to TDC.
Click to expand...
 
I don't know about your T but it is really hard to see the pin on mine, because all of mine have the small pulley. The other issue is, many Model T's have Model A cranks, aftermarket SCAT and Sure Mike crankshafts, and 1920's 4 cylinder Chevrolet cranks. If the hole for the crank ratchet pin is not where it is supposed to be you have no idea whether the piston is actually where you think it is. Good way to get injured.

redmodelt said:
That what the pin in the crankshaft pulley is for. When it's horizontal the engine is at top dead center (3:00) at about 3:15 it just past TDC.
Click to expand...
 
RE; The other issue is, many Model T's have Model A cranks, aftermarket SCAT and Sure Mike crankshafts, and 1920's 4 cylinder Chevrolet cranks." While you do make a good point about the pulley pin hole, I really do not think this is the case here. With the brass or low radiator cars you should be able to look under the radiator and see the pin. I have not heard or see anyone talking about the hole for the crank pulley being different in above cranks, I would think that for the most part people running those will know how to time there modified engines.
 
My point is that my method is easier, quicker, and tells you the actual position of the piston. Your method is hard for an old guy like me who does not like to get on his knees to do anything.
 
:) Ya old guys, I am only 61 but I can get down to the floor, gravity helps with that but getting back up is getting harder. Bad motorcycle accident does not help.

By eye site or plastic straw both way will work.
 
You must log in or register to reply here.
Back
Top