Massey Harris 50 w/ Loader and Finding TDC

[Haminarmor]

I need to find top dead center in a Massey Harris 50.
The loader makes it tough to access the flywheel, (and the #1 plug hole) and now that I’ve reached it it’s very difficult to turn; much tighter than any other time I’ve done this on an engine. It might just be the angle I have to approach it from, or that I can’t wrench it due the front hydraulic pump. Does the front hydraulic pump create drag on the system?
So far I’ve managed to inch the wheel along by looping a rope through the spokes, but if uncoupling the hydro pump would help I’d do it.
Thanks.

 

[Jim.ME]

I need to find top dead center in a Massey Harris 50.
The loader makes it tough to access the flywheel, (and the #1 plug hole) and now that I’ve reached it it’s very difficult to turn; much tighter than any other time I’ve done this on an engine. It might just be the angle I have to approach it from, or that I can’t wrench it due the front hydraulic pump. Does the front hydraulic pump create drag on the system?
So far I’ve managed to inch the wheel along by looping a rope through the spokes, but if uncoupling the hydro pump would help I’d do it.
Thanks.

Welcome to the forums.

Uncoupling the pump will not make a noticeable difference, turning it that slowly with no hydraulic function engaged.

If you are looking for TDC to check timing, it needs to be TDC on compression stroke of #1. The TDC marks line up at TDC of the exhaust stroke as well, that will put timing 180 degrees out.

Do you have all the plugs removed? It should turn easier with all the plugs out and you might be able to turn it with the fan and a bit of pressure on the fan belt. Always turn the correct direction so any gear lash is removed in the correct direction.

Another method. Jack one rear wheel clear of the ground, block the other one to prevent rolling. Put the transmission in high gear and turn the wheel in the forward direction to roll the engine. Always turn the correct direction so any gear lash is removed in the correct direction.

Edited to correct stroke error.

 

[used red MN]

Hello Haminarmor, welcome to YT! Just so we all have an understanding, you are trying to feel the compression at number 1 cylinder closest to the radiator as you turn the engine, is this correct? Trying to understand your “rope in wheel spoke configuration” I take it this is an attempt be able to turn the engine through the gear train and yet be able to monitor the spark plug hole, am I also following this as correct? Jim’s suggestion should be helpful, in particular the choice of gear. The highest gear gives the wheels or drivetrain the most mechanical advantage over the engine. The exact opposite of the engine driving the rear drivetrain, in that respect the engine has the greater mechanical advantage in the lowest gear. Some use a cotton ball in the spark plug hole. When it is blown out you know the piston has started the compression stroke.

 

[Haminarmor]

Beautiful advice. An example of when a spinning wheel actually accomplishes something.
I got that telltale puff from #1 and looked in the peephole for timing marks. Saw no marks on the flywheel.
Turned the wheel a little back and forth and still nothing.
Then I figured I’d wing it, and did the puff of air again, then set the distributor a tiny bit past the #1.
The tractor started, ran rough but I tweaked the distributor and it evened out pretty well. Then it stalled and wouldn’t restart.
Lots of gas dripping from the carb, though.

 

[used red MN]

I am glad that helped you. Sounds as though I left a key detail out that I thought you already knew. When air starts pushing out of the cylinder there is nearly a 1/2 of a crankshaft turn before the piston is at TDC. So in reality it poofs out the cotton ball then you continue turning the engine slowly, watching for the timing marks so you can line it up to TDC.

 

[Haminarmor]

Roger that, used red in MN.
Problem is, I can’t find timing marks on the flywheel through the peep hole, so I went the “seat-of-the-pants” route.
Maybe it’s a replacement flywheel?
Anyhow, it runs a bit rough at higher rpm but won’t idle down past 1200rpm or so, and won’t start when it’s warmed up.

 

[Jim.ME]

Roger that, used red in MN.
Problem is, I can’t find timing marks on the flywheel through the peep hole, so I went the “seat-of-the-pants” route.
Maybe it’s a replacement flywheel?
Anyhow, it runs a bit rough at higher rpm but won’t idle down past 1200rpm or so, and won’t start when it’s warmed up.

The flywheel often needs to be cleaned to see the marks. I have used some medium to fine grit emery cloth looped over the end of a stick to clean the flywheel. Get the rotor pointing at number one terminal in the distributor cap and start cleaning with the emery and some brake cleaner, If it runs the marks should be near either or both sides of that point. You should have a good light as they generally are not that pronounced.