9N starting help

[Reedjp]

Hello everyone, been trying to determine the issues with my ‘41 9N. Historically, it’s started beautifully. However, this spring I was using it to run out wood chipper and later that day our tiller. Once I got started with the tiller, the arms, being sensitive buggers, went up too quickly and I reacted by pushing them down as fast as I could. Immediately after that, I had white smoke coming out the tailpipe and couldn’t keep it started. We pushed it back in the garage and now it won’t start. I’ve replaced spark plugs, checked the spark (though, not with a gap tester), disassembled carb and bought a new one. With air intake off, I get decent suction from carb but it overflows, with both carbs. I’m lost and frustrated at this point as it’s a beautifully restored tractor from my wife’s family. Any help would be appreciated.

 

[trav_marq]

That white smoke could indicate head gasket problems. Might have to take the head off if you're getting any coolant in the system, could be why you're having trouble keeping it started. Just an idea though.

 

[Bruce(OR)]

Sounds like multiple problems.
Is the engine oil milkshake brown?
When you pulled the plugs, were any dripping wet?
Did the exhaust have a sweet smell to it when it was last running?
Comp check is what in the cylinders?
If you have a rad pressure checker, fill the rad and pressurize it with the plugs out. Coolant should fill the bad cylinder.
That's enough for now from me.

 

[Eman85]

Replacing parts without diagnosis usually just wastes time and sometimes parts.
You had the plugs out, great time for a compression tests. Did any of the plugs appear exceptionally clean, steam is a great cleaner. Are any of the fluids low, smoke usually requires a fluid. Not sure what you mean by carburetor overflows.

 

[Reedjp]

Replacing parts without diagnosis usually just wastes time and sometimes parts.
You had the plugs out, great time for a compression tests. Did any of the plugs appear exceptionally clean, steam is a great cleaner. Are any of the fluids low, smoke usually requires a fluid. Not sure what you mean by carburetor overflows.

Yes, an unfortunate realization once I started the process. The plugs were carbon fouled and the new ones are dry. Still looking into the rest but by carb overflowing, I meant that gas was draining out of the sediment bowl.

 

[Reedjp]

Sounds like multiple problems.
Is the engine oil milkshake brown?
When you pulled the plugs, were any dripping wet?
Did the exhaust have a sweet smell to it when it was last running?
Comp check is what in the cylinders?
If you have a rad pressure checker, fill the rad and pressurize it with the plugs out. Coolant should fill the bad cylinder.
That's enough for now from me.

Engine oil: normal color
Spark plugs: originals when the smoke occurred are carbon fouled, new ones are dry.
Compression check: still need to do, don’t have tester
Noted on rad, just don’t have a checker
Thank you!

 

[Reedjp]

That white smoke could indicate head gasket problems. Might have to take the head off if you're getting any coolant in the system, could be why you're having trouble keeping it started. Just an idea though.

This is my biggest concern and why I’m hoping that I can diagnose everything else before going this route. Thank you!

 

[bluerooster]

Let's start with the fire hazard, and fix the fuel leak from sediment bowl. Could be manifold gasket. Allowing an extremely lean mixture. (I have that trouble with my 2N. (gasket ordered) Simple diagnosis; I would pull all the plugs, put some gas, (mabe a teaspoon full) in each cylinder, replace the plugs and try to start. If it fires, then you may have a vacuum leak due to manifold gasket, bad valve, head gasket.... These tractors inherently run a bit rich, so carbon black plugs is not unheard of. head gasket blown between two cylinders could be a possibility, but it should still fire and run on the other two. (albeit with way less power, and rough as all get out) Just for spits and giggles, you can put some grease around the joint where the intake meets the block, It will temporarily seal any suspected leak. If it then starts and runs, you have found the trouble.

 

[Eman85]

Yes, an unfortunate realization once I started the process. The plugs were carbon fouled and the new ones are dry. Still looking into the rest but by carb overflowing, I meant that gas was draining out of the sediment bowl.

Sediment bowl is the glass bowl at the fuel tank shutoff, do you mean that is leaking?
Simple radiator pressure test, use the compression of the engine. Remove the fan belt and have someone turn the engine while you look in the radiator. If you have a head gasket problem it will push air into the radiator. Should still do a compression test. Also buy a spark tester and check the spark. Also do a fuel flow test at the plug at the bottom of the carb. Shut fuel and remove plug then turn the fuel on and see how long it takes to fill a pint jar.

 

[Reedjp]

Let's start with the fire hazard, and fix the fuel leak from sediment bowl. Could be manifold gasket. Allowing an extremely lean mixture. (I have that trouble with my 2N. (gasket ordered) Simple diagnosis; I would pull all the plugs, put some gas, (mabe a teaspoon full) in each cylinder, replace the plugs and try to start. If it fires, then you may have a vacuum leak due to manifold gasket, bad valve, head gasket.... These tractors inherently run a bit rich, so carbon black plugs is not unheard of. head gasket blown between two cylinders could be a possibility, but it should still fire and run on the other two. (albeit with way less power, and rough as all get out) Just for spits and giggles, you can put some grease around the joint where the intake meets the block, It will temporarily seal any suspected leak. If it then starts and runs, you have found the trouble.

Poured a teaspoon of gas into the spark plug holes and it started for a brief second. Long enough to see the white exhaust again. Got a good whiff of it and it is indeed sweet smelling. I think at this point I should just move straight to the head gasket, correct?