TO30 starts hard and runs rough

Replacing a bad component with a new but still bad component is a common problem. Check the quality of the spark because that is easy and often all that is needed is cleaning the ignition points. Your spark should be able to jump a 1/4 gap every time and be a strong blue-white in color.
 
Run a compression test.

Even if decent compression, open the valve cover, check that all the valves are
opening and closing, look for broken springs, bent pushrods.
 
No comp gauge?
Thumb over the plug hole and bump it over.
Enough comp will blow your thumb of the hole.
If the same on all 4 holes, crossed the plug wires?
 
.

Remove each plug and check condition of them, keeping plug by cylinder order. Look up 'spark plug visual diagnostics' and that will give you clues. I chased one tractor this spring that had fouled plugs, but I'd replaced a few other parts because "those plugs should be fine" since they were replaced just last fall...

Get a compression tester at Harbor Freight and test all cylinders. If the engine hasn't run a lot or in a long time, there can be rings sticking that will free up with use. Some put a little oil down the spark plug hole after first compression test, to see if compression goes up (tells if the problem is piston or valves).

Verify firing order from distributor is correct. Line up cylinder #1 with distributor #1 post. I bought a TO-35 the previous owner had swapped two of the four, it sort of ran but barely. Could be a bad spark plug wire. Harbor Freight sells a unit you plug in between the spark plug and plug wire that glows when it gets spark, but it's 12v and some tractors are still 6v and may not indicate anything.

Old fuel, plugged fuel line/carb.

Figure out a way to split the problem: is it electrical, fuel, or compression?

.
 
[i:330b4af363]Harbor Freight sells a unit you plug in between the spark plug and plug wire that glows when it gets spark, but it's 12v and some tractors are still 6v and may not indicate anything.[/i:330b4af363]

That gizmo will work just fine, because to fire a plug takes the same voltage be it a 6v or 12v system.

I keep a binder on all my old junk listing any repairs & their part numbers, test results such as compression tests, carburetor jet changes, timing etc., and other actions by mileage or hours. I have too many vehicles to keep track of what gets done to which & when

I number each spark plug with a Sharpy on the porcelain so it gets back to the same cylinder each time. One can keep a record of how each plug looks each time it is removed.

My TO 30 has a very badly worn valve seal on #4, that plug carbons up real fast, and will misfire after a few hours of operation. At which time I pull all four plugs, clean #4, and the other three if needed due to their seals not sealing as well as they need to.

As mentioned above, check the points gap making sure the cam that the points ride on to open and close is lubricated, and clean them with a point file or very fine emery cloth or sand paper. If they are burnt, plan on replacing them along with the condenser as soon as you can. Inspect the distributor cap for carbon tracks, and cracks both of these conditions will cause misfires.

Sometimes a failing coil as it heats up will cause misfire before they it fully shorts out internally.
 
One more thought:

If the exhaust valve lash has tightened up that will cause poor idle and missing under load. When that happens the exhaust valve wont fully close during the compression stroke causing a misfire due to the drop in cylinder pressure.

It is a PIA the check the lash because one needs to remove the gas tank to be able to access and pull off the valve cover. But once the valve is uncovered, it is a simple task to adjust the lash.

My Slant Six has the same over head valve configuration as the TO 30 excepting there are small caps riding on top of the valve stems. The feeler gauge has to be passed between the rocker arm and top of the small cap.

Settings for TO-30 lash on both intake and exhaust valves are:
0.015" (cold around 70 degrees)
or
0.013" hot


Video here on lash adjustment

Disregard the slant six measurements mentioned in video.
 
Yep!
He found the wires were crossed and all is fine now and he thanks one and all for the wonderful suggestions.
He appreciates all the time people spent giving him input on his problem.
He also wishes everyone well and especially expresses wishes for a Merry Christmas for all should you not hear from him again in the future.
 
Quite often the case is the easiest solution turns out to be what fixes the problem after too much overthink, and pulling the trigger on the parts cannon.
 
How do I get a quarter inch spark and blue? And what is the easiest way to be sure that it is in time?

I am still not able to get it to start after cleaning the points and checking the rotor cap and rotor and I am getting some spark to each of the plugs
 
(quoted from post at 11:30:21 09/16/22) How do I get a quarter inch spark and blue? And what is the easiest way to be sure that it is in time?

I am still not able to get it to start after cleaning the points and checking the rotor cap and rotor and I am getting some spark to each of the plugs

You can take an old spark plug and open the gap to 1/4 inch and use that to check for strong spark. I don't think it has to be blue or white.
You originally said that it still runs rough after replacing ignition and fuel system parts. Now you say it won't start at all. Is your battery fully charged? I don't remember if you said it's 6 or 12 volt.
Did you ever do a compression test?
 
(quoted from post at 10:05:35 09/18/22)
(quoted from post at 11:30:21 09/16/22) How do I get a quarter inch spark and blue? And what is the easiest way to be sure that it is in time?

I am still not able to get it to start after cleaning the points and checking the rotor cap and rotor and I am getting some spark to each of the plugs

You can take an old spark plug and open the gap to 1/4 inch and use that to check for strong spark. I don't think it has to be blue or white.
You originally said that it still runs rough after replacing ignition and fuel system parts. Now you say it won't start at all. Is your battery fully charged? I don't remember if you said it's 6 or 12 volt.
Did you ever do a compression test?

I did a compression check. 1 is 100. 2 is 85. 3 is 105. 4 is 110
Fully charged the battery. 12 v system. Still no start now.
 
The compression is good enough to run. One soft cylinder, but it should still start. What have you done between the time you replaced "all electrical and fuel and it still runs rough" and now that it won't start at all?
Have you tried starting fluid sprayed onto the carburetor intake?
At this point I would put the old carburetor back on and see if it will at least start.
 
(quoted from post at 09:53:03 09/19/22) The compression is good enough to run. One soft cylinder, but it should still start. What have you done between the time you replaced "all electrical and fuel and it still runs rough" and now that it won't start at all?
Have you tried starting fluid sprayed onto the carburetor intake?
At this point I would put the old carburetor back on and see if it will at least start.
When the new carb and electric was put on. The tractor ran well enough to run the bush hog and then it ran out of gas. When we put gas in it we were able to get it started once and it was very rough. No it does not start. I tried started fluid. But no luck
 
When you run out of gas, there's a good chance that sediment from the bottom of the tank got into the filters and plugged them up or even got into the carburetor. Remove the plug at the bottom of the carburetor and make sure you have a good flow through the carburetor. You should be able to fill a pint jar in a couple of minutes. If not, then start checking the filters. There should be one at the top of the fuel bowl under the tank, and another one in the carburetor inlet.
I would still put the old carburetor back on. The after market ones that you can get probably are made in the land of almost right and can cause trouble.
 
(quoted from post at 14:24:53 09/19/22)
(quoted from post at 09:53:03 09/19/22) The compression is good enough to run. One soft cylinder, but it should still start. What have you done between the time you replaced "all electrical and fuel and it still runs rough" and now that it won't start at all?
Have you tried starting fluid sprayed onto the carburetor intake?
At this point I would put the old carburetor back on and see if it will at least start.
When the new carb and electric was put on. The tractor ran well enough to run the bush hog and then it ran out of gas. When we put gas in it we were able to get it started once and it was very rough. No it does not start. I tried started fluid. But no luck

If it won't even fire on starting fluid, you have spark problems.
 
(quoted from post at 06:01:37 09/10/22) I have replaced everything electrical and the fuel system and it still runs very rough
What next?
I'm sure you are aware of the rotor turns counter clockwise .
 
(quoted from post at 11:26:40 09/22/22)
(quoted from post at 06:01:37 09/10/22) I have replaced everything electrical and the fuel system and it still runs very rough
What next?
I'm sure you are aware of the rotor turns counter clockwise .
If you have decent compression. Does it mean the valves are working properly?
 
(quoted from post at 18:07:35 09/22/22)
(quoted from post at 11:26:40 09/22/22)
(quoted from post at 06:01:37 09/10/22) I have replaced everything electrical and the fuel system and it still runs very rough
What next?
I'm sure you are aware of the rotor turns counter clockwise .
If you have decent compression. Does it mean the valves are working properly?

Working and sealing might be two different things.

Working I would consider opening and closing. Sealing would be working without leaking.

When you sort out other problem check compression on #2 with a few squirts of oil. If it comes up might be rings sealing. If not check valve lash. A too tight valve will cause low compression, as will bad valve/seat.
 
(quoted from post at 05:09:22 09/25/22)
(quoted from post at 18:07:35 09/22/22)
(quoted from post at 11:26:40 09/22/22)
(quoted from post at 06:01:37 09/10/22) I have replaced everything electrical and the fuel system and it still runs very rough
What next?
I'm sure you are aware of the rotor turns counter clockwise .
If you have decent compression. Does it mean the valves are working properly?

Working and sealing might be two different things.

Working I would consider opening and closing. Sealing would be working without leaking.

When you sort out other problem check compression on #2 with a few squirts of oil. If it comes up might be rings sealing. If not check valve lash. A too tight valve will cause low compression, as will bad valve/seat.

The valves all look to be opening and closing properly. I have all the plugs out and the starter is having a hard time turning it over.
I will attempt to lash the valves and put it back together. Anything else I should be looking for while in side?
I have been running this tractor for 6 years and never a problem.
Is it possible it got hot and blew the head?
 

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