# 49 8n 12v



## Thatone8nthatwontrun (3 mo ago)

So. I have a 49 8n that has sat and not run for quite some time, I had fire on one cylinder, pulled the wires and could tell they needed replacement, so I replaced them, and messed with the points a little, got all four firing, used to run on propane, but I’ve since switched it back(it was my grandfathers) but I’m getting fire on all 4 but won’t start. I’m getting good fuel to the carb. Any ideas?


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## pogobill (Jan 31, 2012)

Welcome to the forum. Have you taken the bottom off of the oil bath air filter to see if it's letting enough air through? Also if it's been sitting, check to see if there are any critters nesting or plugging the exhaust. Both easy checks.
Then look at the plugs to see if they are getting wet with fuel. If not you have a fuel issue. Are the plug wires back running to the proper plugs? Is the spark coming at the proper time? 
Have you a operators / owners manual for the tractor?


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## Thatone8nthatwontrun (3 mo ago)

pogobill said:


> Welcome to the forum. Have you taken the bottom off of the oil bath air filter to see if it's letting enough air through? Also if it's been sitting, check to see if there are any critters nesting or plugging the exhaust. Both easy checks.
> Then look at the plugs to see if they are getting wet with fuel. If not you have a fuel issue. Are the plug wires back running to the proper plugs? Is the spark coming at the proper time?
> Have you a operators / owners manual for the tractor?


I can hear air easily coming out of exhaust, I pulled the boot off of the oil air filter I know I’m getting fuel to the car, what would stop it from goin too the plugs wires are on the right plugs I believe, and I don’t know how the spark wouldn’t be coming at the right time. Thank you for the welcome


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## linquistmarc (5 mo ago)

The distributor was probably advanced some to get it to run right on propane, so double check the plug wire location on the distributor cap so you don’t blow your muffler off😏 and retard the timing a little and I think you will get it going. Make sure that point gap is dead on too, that will keep you guessing sometimes.👍


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## Thatone8nthatwontrun (3 mo ago)

linquistmarc said:


> The distributor was probably advanced some to get it to run right on propane, so double check the plug wire location on the distributor cap so you don’t blow your muffler off😏 and retard the timing a little and I think you will get it going. Make sure that point gap is dead on too, that will keep you guessing sometimes.👍


Can you tell me the firing order?


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## Joe.S.AK (Nov 26, 2020)

So, #1, First of all a hearty welcome!










OK, an observation: It was running on Propane - was the carb ""adjusted"" to compensate for the "new" fuel long ago? If so, it seems to be a simple carb check and then a 'tune-up' should do you. Field strip the carb and clean it until it shines (OK - just very clean). Pre-set the carb jets to the +- standard (In fully and then back 1.5 - 2 turns). 

The timing thing is a wise thought --- just-in-case. After that she should start

If not, another 'thing' you could try is pulling the plugs (check for the proper type and their gaps) and then put ~~1/2 teaspoon squirt of fuel in each cylinder. See if she fires off with that sort-a carb bypass and if so then adjust the jets in the carb as you normally would do.

Let us know how it turns out. - Joe -


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## linquistmarc (5 mo ago)

Thatone8nthatwontrun said:


> Can you tell me the firing order?


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## Joe.S.AK (Nov 26, 2020)

Thatone8nthatwontrun said:


> Can you tell me the firing order?


1,2,4,3 - #1 is furthest forward (radiator end)


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## Joe.S.AK (Nov 26, 2020)

One thing #1, you said "I’m getting good fuel to the carb. "Fuel + air burns in the cylinders - so, are you sure fuel + air is going into the cylinders? Try the little squirt of fuel into each spark plug hole deal, rig the plugs up and see if she fires off for a second or two. Exercise in "Proof of Concept" there. I'm thinking that a little chunk of something is jammed in the float needle valve - meaning the fuel can't get past that could-be-obstructed tiny valve opening. That would mean plenty of fuel to the carb but none out to the cylinders.


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## Thatone8nthatwontrun (3 mo ago)

Joe.S.AK said:


> One thing #1, you said "I’m getting good fuel to the carb. "Fuel + air burns in the cylinders - so, are you sure fuel + air is going into the cylinders? Try the little squirt of fuel into each spark plug hole deal, rig the plugs up and see if she fires off for a second or two. Exercise in "Proof of Concept" there. I'm thinking that a little chunk of something is jammed in the float needle valve - meaning the fuel can't get past that could-be-obstructed tiny valve opening. That would mean plenty of fuel to the carb but none out to the cylinders.


I’ve had the carb off, I can blow through all the ports, I’ve got a new carb coming, I’m gonna replace plugs tmrw, give this old marvel one more chance, then wait till Saturday if that don’t do it. But is there a chance the distributor can be 180 degrees out, and keep it from running, I’m not even getting so much as a hit at the moment though


[/QUOTE]


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## linquistmarc (5 mo ago)

Thatone8nthatwontrun said:


> I’ve had the carb off, I can blow through all the ports, I’ve got a new carb coming, I’m gonna replace plugs tmrw, give this old marvel one more chance, then wait till Saturday if that don’t do it. But is there a chance the distributor can be 180 degrees out, and keep it from running, I’m not even getting so much as a hit at the moment though


[/QUOTE]
With the distributor cap off, and using the diagram above the #1 cylinder should be at Top Dead Center (TDC) when the rotor is pointing at the position where #1 plug wire is connect to the cap. The timing mark on the flywheel should be on the TDC mark. If any of these are out of alignment then it is either your piston is on the exhaust stroke or your distributor may be 180 deg. out of alignment.


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## Joe.S.AK (Nov 26, 2020)

AHHhhhhhhh #1,

If you've removed the Distributor there is something to know --- The slot drive to turn the Distributor is *slightly* OFF CENTER. Don't just throw it back together thinking that the slot and tang are centerline symetric. If it's mis-aligned and then firmly bolted back it *Could*, easily, break the distributor itself. 
Align the distrib back in place (using less than finger tight on the bolts) and then slip / rotate the distrib's shaft until it goes back offset like it came apart. After you're happy with it snug the bolts a little to make sure you're A OK. 

OH - on buying another carb from the net - NOT such a good idea. The engineers in China were having a bad year when they reverse engineered (Yeah, 'Cloned') these Ford Carbs. Shiny and nice looking and also rarely work. Go to a reputable parts dealer on the net and buy a full rebuild kit. Email me for ideas and sources.

Joe


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## Joe.S.AK (Nov 26, 2020)

Well - The Rest of the Story --------------------------------

#1 called me about an hour ago - and after spending a ton of hours again today he was finally able to get his grandfather's 8N running late today. The carb still needs a full rebuild but he said he was able to drive it around a little. 

Now it's just a matter of fixing the thousands of 'little things' and he'll be out bush hogging in a week or two (or 3, or 4, or .......... 
Motivated tenacity with a will to succeed finally did it. 🎖

WAY TO GO #1!

- Joe -


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## linquistmarc (5 mo ago)

Joe.S.AK said:


> Well - The Rest of the Story --------------------------------
> 
> #1 called me about an hour ago - and after spending a ton of hours again today he was finally able to get his grandfather's 8N running late today. The carb still needs a full rebuild but he said he was able to drive it around a little.
> 
> ...


Hold on Joe! Don’t leave us hanging here. What did he do to get it to finally start. Was it the carburetor or electrical/ignition?


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## oletrapper (5 mo ago)

linquistmarc said:


> View attachment 82987


Love those diagrams Linquistmark> 😀


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## oletrapper (5 mo ago)

That one 8N, 
I saw the title of your thread and have read it all. Very interesting. I was 7 years old when that tractor was built.  Dating myself but that's okay. When I bought our farm in 1971, the 8N was my first tractor. A real work horse. Personally, I have never seen one that ran on propane. I have heard of it but just never seen one.
Treat yours with TLC! 
Change the oil, Transmission/gearbox oil, etc. Especially the air breather bath. Remove it and soak in a mixture of gas and diesel fuel. About 3 to 1 mix. 3 diesel, 1 gas. 
Yours may already have an overrun clutch on the PTO shaft which is a MUST if you plan to bushhog with it. If it doesn't, you need to buy one. If you bushhog without it without an override, the bushhog will push you over a hill or into a tree sure as the world. I know from experience. :-(
We don't know what exactly fixed your problem but please let us know. Something to watch for in the future when you get it going good is the ignition system. You stated that is 12V. The originals were 6V. Just remember if you replace anything like the coil, condenser next to the points that you get 12V. Your starter motor was probably left as 6V unless it has been rebuilt. A 6V starter motor will last a long time as long as you don't have to crank the engine for long periods. If you do, it will burn it up. Again, I know from experience. lol 
Good luck with it. OT


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## oletrapper (5 mo ago)

I forgot to include this with my earlier post. Overrun/override clutch.




 OT


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## plarrydean1977 (4 mo ago)

Thatone8nthatwontrun said:


> So. I have a 49 8n that has sat and not run for quite some time, I had fire on one cylinder, pulled the wires and could tell they needed replacement, so I replaced them, and messed with the points a little, got all four firing, used to run on propane, but I’ve since switched it back(it was my grandfathers) but I’m getting fire on all 4 but won’t start. I’m getting good fuel to the carb. Any ideas?


the jetting on carb is way diff from propane than gas


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## jrelkhunt (8 mo ago)

Thatone8nthatwontrun said:


> So. I have a 49 8n that has sat and not run for quite some time, I had fire on one cylinder, pulled the wires and could tell they needed replacement, so I replaced them, and messed with the points a little, got all four firing, used to run on propane, but I’ve since switched it back(it was my grandfathers) but I’m getting fire on all 4 but won’t start. I’m getting good fuel to the carb. Any ideas?





plarrydean1977 said:


> the jetting on carb is way diff from propane than gas


turn on the ignition


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## linquistmarc (5 mo ago)

oletrapper said:


> Love those diagrams Linquistmark> 😀


Thanks


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## Joe.S.AK (Nov 26, 2020)

Well, for starters, the phone connection wasn't all that hot. I understood it was a Gasoline through the Carb problem. I suspect that #1's Grandfather had to adjust it to accommodate the Propane as fuel. #1 sent me a short (6 second!) email phone video and the The OLD Propane set-up SEEMED to be a combination of a small, old, house style regulator going through Copper tubing into the carb and then, with the mixed in air went to the cylinders. 
Of course, the tractor HAD been sitting for 10 years and his Grandfather had been running it for quite a while before that so it could have been Propanized 20+- years ago.

For what his Grandfatherhad to work with back then it was a slick set-up. I think that the whole sticking point on the no start problem was that the carb hadn't seen gasoline in a ..L..O..N..G. time and that it was almost certainly 'tweaked' for Propane in not only the carb but possibly in the dwell angle and point gap. 

At any rate, that young lad (#1) just wouldn't let loose until he got it fired up. He did gall up the brass float valve seat in the effort so I suggested a rebuild kit and a FO-4 shop manual to bring things back to factory and learn more.

He seemed like a really nice fellow - I wish him well. BTW - he has my cell # if he needs anything else all he needs to do is call.

- Joe -


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## John Liebermann (Sep 17, 2018)

In a situation like this I give er a small snort of starting fluid to see if spark works. If it fires you know you have electric.


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## Joe.S.AK (Nov 26, 2020)

The 'Biggie' here is simply did the fuel / air mix made it ALL the way to the cylinders. Just getting gasoline to the floats doesn't ensure it goes all the way to the "Boom Boom Spots". New plugs and wires solved that 'sketchy" spark problem and rummaging around inside the carb, it would seem, dislodged junk and blew the jets out. VOILA! The fuel got through, mixed with the air and continued into the cylinder.

No "Head Lifter" spray needed.


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