Tdc on John Deere 2550

[Colt9556]

John Deere 2550 need help on how find top dead center can’t find any marks on flywheel kinda lost needing to run valves on new head

 

[cole in mo]

John Deere 2550 need help on how find top dead center can’t find any marks on flywheel kinda lost needing to run valves on new head

Mabey the marks are on the front pully, turn the engine by hand in the right direction, watching the #1 rocker arms. When the intake arm closes, turn the engine a little more, clean the front pully, looking for timing marks, same with the flywheel.

 

[Dieseltech]

Watch the rocker arms, you don't need exact TDC on a four cylinder engine. Bump engine over and when one rocker EHAUST valve just closes and the INTAKE starts to open you can set both rocker arms on the other paired piston. Cylinders 1 and 4 are at TDC together, and 2/3 are at TDC together. So when 4 arms are rocking, set 1. When 2 arms are rocking set 3. Etc.

 

[Fixingfarmer]

I believe there is a line on the pulley and a raised green ridge on the front cover

 

[matthies]

You have to remove odd shaped cover on the left rear of the engine. Usually a diamond shape with a double ended bolt, smooth on end you see, and threaded on the other into the block. Remove the bolt and cover, then push a 3 inch 5/16 bolt into the hole and slowly bar engine over. When the bolt falls in a 1/2 inch you are at TDC, then set 4 valves, turn engine over one rev and adjust last 4 valves.

 

[matthies]

You have to remove odd shaped cover on the left rear of the engine. Usually a diamond shape with a double ended bolt, smooth on end you see, and threaded on the other into the block. Remove the bolt and cover, then push a 3 inch 5/16 bolt into the hole and slowly bar engine over. When the bolt falls in a 1/2 inch you are at TDC, then set 4 valves, turn engine over one rev and adjust last 4 valves.

Insert the 5/16 bolt into the threaded hole.

 

[Jim.ME]

You have to remove odd shaped cover on the left rear of the engine. Usually a diamond shape with a double ended bolt, smooth on end you see, and threaded on the other into the block. Remove the bolt and cover, then push a 3 inch 5/16 bolt into the hole and slowly bar engine over. When the bolt falls in a 1/2 inch you are at TDC, then set 4 valves, turn engine over one rev and adjust last 4 valves.

x2 If it is a 2550 Ag tractor. If it is a 2550 riding mower different info is needed. Got to love reusing model numbers.

One needs to look at the valves to see which cylinder is at TDC compression, ready for the valves to be set, as #1 and #4 are TDC at the same time and the pin will drop in.

Colt9556,
You say you are replacing the head, what are you using for a manual to guide you and specs? The service manual (TM4403) tells you how to do it and which valves can be set, based on whether #1 or #4 is TDC compression and only requires one 360-degree rotation after TDC #1 compression is found.

 

[Cliff Nelson]

Insert the 5/16 bolt into the threaded hol

Insert the 5/16 bolt into the threaded hole.

You can use the double ended bolt as the timing pin.