SMTA...hope this is not a dumb question

Dave H (MI) · Nov 3, 2019

I had asked about replacing a seal on the live hydraulic pump because I have oil in the distributor. I understand about setting #1 to top dead center and the soda straw in the spark plug hole...BUT...how do I know this is TDC on ignition and not exhaust? It matters I would think right? I removed a distributor one time only, maybe 15-20 years ago on a Farmall B. Isn't there a mark or such on the flywheel that I need to mark with some white paint or marker so that I make sure it stays there during the repair? I cannot do this repair right now because the tractor died outside and the weather is just too chancy, but I want to use the winter months to make sure I understand the process before I screw up one the hardest working tractors I own.

D Slater · Nov 3, 2019

Remove the distributor cap. Turn engine until pointer on rotor points to near the terminal number one spark plug wire is on. Then line up the pointer with notch in front pulley and that will be on compression stroke. When installing distributor get the rotor pointing at the same place. Engine would need to turn another revolution to be off the compression stroke if running okay if located like above. Original front pulley on a SMTA will just have one notch.

SkipperII · Nov 3, 2019

Put your thumb over the spark plug hole, bump the engine over, or have someone rotate it manually, and feel for the pressure to push on your thumb, then line up the timing mark. I'm not an IH guy, so I can't tell you where that's at. Some are on the front engine crank pulley, some on the flywheel.

gene bender · Nov 3, 2019

if you put the dist back in with the rotor pointed the same as when you took it out you will be just fine if you do not turn the engine over disconnject the ground from the battery that way you know someone has not turned the engine over without dist installed. I pull them all the time and it just works same as pulling a mag

F-Dean · Nov 3, 2019

Take the valve cover off and watch the rocker arms. If both exhaust and intake valves are up (closed) it is compression. If they are not both "up," it is exhaust.

rustred · Nov 3, 2019

that wont tell you unless u watch the running mate , #4 cyl. its valves must be on the rock. When at TDC #1 and #4 cyl valves are up. just that #4 is on overlap so #1 has to be on compression.

Hayfarmer · Nov 3, 2019

only trouble I ran into. marks on drive gear are on the front, towards front cover but you can find them with mirror. If you are off a tiny bit you can fix it with distributor timing

used red MN · Nov 3, 2019

Wow, take the valve cover off to just remove and replace the hydraulic pump and distributor on an engine that was running fine? Do what D Slater recommends and all will be fine.

Dave H (MI) · Nov 3, 2019

I gotta say you guys made me feel a little better about this process. I don't mind dinking around with the B or the Super A but the SMTA cuts, rakes and bales all my hay on this side of town and I am going to need it pretty quick come Spring. Just have to dust off my memory and print out your responses and think I can muddle thru. Much appreciated!

F-Dean · Nov 3, 2019

I do not have a SMTA, just a couple of Ms. On a standard M, it is easy to take the valve cover off.
On an M, #1 will have both valves closed at TDC of its compression stroke -- they will have been closed for 180 degrees.

SMTA...hope this is not a dumb question

Dave H (MI)

Well-known Member

D Slater

Well-known Member

SkipperII

Well-known Member

gene bender

Well-known Member

F-Dean

Well-known Member

rustred

Well-known Member

Hayfarmer

Well-known Member

used red MN

Well-known Member

Dave H (MI)

Well-known Member

F-Dean

Well-known Member

Similar threads