# Ford 8n Valve removal



## Mike77

I have an old Ford 8n that was smoking badly so I removed the engine head to find the valves and pistons caked in carbon. While I plan on cleaning the pistons and replacing the rings I don't know how to remove the valves. Any tips?


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## JimCobb

Hi,
If you plan to ring the engine and are not familiar enough with the job to remove the valves you need to find someone to give you a hand.
Also the rings are not the only thing that will cause smoke you will find that you may need valve guides and seals to only replace the rings is money waisted and all of your work lost.
If you like the tractor go on and do a complete job or you will only regret what you have done.
Signed ,
The voice of experience


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## Mike77

Thanks for the advice those it shop manuals only helped me so much.


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## stephenscity

The valves are pretty easy to remove with the head off. You need to suppress the spring then remove the spring clip remove the old valve seal and it should slide out. Check your guides and see if they need to be replaced. I have to agree if you have gone this far I would do it right not that exspesive to get the head done Only you know how far ya want to go but with that much carbon sounds like bad valve seals.
One word of caution when you take a head off and you don't resurface it might not seat back right.


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## Mike77

Sounds good and thanks. I've been cleaning carbon off the head and pistons for weeks. Now I have to get a spring compressor since pushing the guides down with conventional tools is turning out to be barbaric.


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## stephenscity

Have you had any progress?Got an update?


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## Mike77

Nothing new yet. Took a Break from that to set up the onion planter on the cub. I should have an update by early spring since school is starting up


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## TonyH

Just general Mechanic knowledge, not 8N specific.
If the Cylinder walls do not have a ridge at the top ( close to the Head) then you probably don't need Rings. 
The Ridge would indicate the Cylinder walls are worn.
Are these Heads build like car engines where the Valves pass through the Guides then comes te Spring and the Washer that is all held together with Keepers?


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## Mike77

TonyH said:


> Just general Mechanic knowledge, not 8N specific.
> If the Cylinder walls do not have a ridge at the top ( close to the Head) then you probably don't need Rings.
> The Ridge would indicate the Cylinder walls are worn.
> Are these Heads build like car engines where the Valves pass through the Guides then comes te Spring and the Washer that is all held together with Keepers?


I'm not so sure what to say since this is my first machine but the valves are order the way you listed.


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## TonyH

Again, this is not 8N engine specific. not sure how they did their Head
http://www.sjdiscounttools.com/kdt383.html

A tool like this holds the Valve as it compresses the Spring so you can get the Keepers off. 
If you run your fingernails up to the top of the cylinders, will they run all the way until they come out of the cylinder or is there a Ridge about 1/4" down?
Did the engine smoke as soon as you started it or did it take some time. If it smoked right away but then slowed down for a bit then smoked badly after that, it might be just guides and valve stem seals. Or maybe just the old dried out.. maybe missing stem seals. Yahoo Valve Stem seals to see what they look like.


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## st3gamefarm

TonyH said:


> Just general Mechanic knowledge, not 8N specific.
> If the Cylinder walls do not have a ridge at the top ( close to the Head) then you probably don't need Rings.
> The Ridge would indicate the Cylinder walls are worn.
> Are these Heads build like car engines where the Valves pass through the Guides then comes te Spring and the Washer that is all held together with Keepers?


 It's a flathead, so servicing the head would just be cleaning and re-surfacing.

As to the valves, Yes, springs, guides, and keepers. 
I dont know if the guides are one or two piece, but someone here can shed more light on that. As to valve guide seals, I dunno, But see no real reason for them on the inverted valves.


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## Mike77

@TonyH the engine would just be able to start and sometimes not at all. Went through a lot of ethanol to get it going and when she did run it was thick blue smoke out of the gate. Granted we did get a lot of plowing and tilling done but the lack of hp was palpable.


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## Sanddawg

A link that maybe of help to you:

http://www.ntractorclub.com/howtos/howtos.htm

Manuals:

http://www.ntractorclub.com/forums/manuals/manuals.htm

Look under "Service/Troubleshooting (20)" and also look under "Tractors (58)" for the information you need.


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## Mike77

I actually have that first site printed out and while it has helped that whole screw driver thing did not help me remove the valves. As for manuals I really praise it manuals but the valve removal was like the one thing they did not cover.


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## Mike77

Ok I got back from college and finally getting back to work for this short week. So far the cylinder head is the only thing clean but I should be getting those valves out and lapped in the near future


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## dawzie

Welcome to the site. Just a little info. From what I see your tractor is a 2-N or 9-N not an 8-N. Might matter in getting parts. In order to adjust the valves there is a special tool needed. On one of these tractor sites I saw it being used during a rebuild.

If you could get a couple of pics. of the cylinders with the rags out would be helpful to see how they look for wear.


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## Mike77

I can get those pics but the cylinder walls are in very good condition. No ridges or scratches to be seen.


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## Mike77

Ok guys I could use a tip again. I attempted to remove the valves and while I got one out the rest are stuck tight and so far wd40 was unable to free them. I want to save these valves since the seats are in good condition and 200$ for new valves is expensive for a college kid. Any suggestions?


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## stephenscity

Try soaking them for a couple days with your favorite penatrant. I like PB Blaster but sure someothers work just as well.


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## Sanddawg

My favorite homebrewed penetrant is 1 cup of automatic transmission fluid (ATF) to 1 cup of acetone, then soak...wait...try...soak...wait...try again until they loosen up. The ATF acts as a cleaner, acetone thins the ATF so it will penetrate faster. You can adjust the mixture as needed, a little more or less of acetone may help. Take your time and slowly work the valves back and forth until they loosen up.

Good luck on the stuck valves.


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## stephenscity

Kept that mixture sounds good!!Thanks Would be a lot cheaper!!!


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## Mike77

I can give it a try since our forklift uses ATF as power steering substitute. It's l the lack of experience with machines that's putting a damper on this project. Sometimes I wish the flat tire was all I had to fix


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## TonyH

WD-40 is a usless lubricant. It is nice to use to find a squeakbut then you must go back and lubricate it properly. It is absolutely useless as a Rust Pentrator. BBlaster, Kroil or anything actually designed to penetrate stuck hardware will work better then fish oil (WD-40)


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## terry piper

would a valve spring compressor work?


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## Patcroy

stephenscity said:


> The valves are pretty easy to remove with the head off. You need to suppress the spring then remove the spring clip remove the old valve seal and it should slide out. Check your guides and see if they need to be replaced. I have to agree if you have gone this far I would do it right not that exspesive to get the head done Only you know how far ya want to go but with that much carbon sounds like bad valve seals.
> One word of caution when you take a head off and you don't resurface it might not seat back right.


Heads are quite thick and I haven’t seen one warp yet. Gaskets are quite good these days and still available at car part stores. Likely the valve that stick is the intake as it has a rubber ring whereas the exhaust doesn’t.


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## allanworks

anything that comes in contact with the combustion chamber, exhaust, and baked in oil I like to soak in seafoam overnight then spray down with PB blaster. my theory with it is it eats up the carbon allowing the PB blaster to soak further in. it rarely fails me and if it does you're probably gonna need a torch anyways to get it out. you should not need a valve spring compressor just a flat head screwdriver wedged between the spring and the hole in the block pushed down should release the tension off the valve spring keeper.


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## Patcroy

I had to remove the valve spring retainers clips for exhaust cylinder 1 and 2 then force down the valve stem guides with a hammer and large socket. These brass guides were seized in there bad. The rubber o ring gaskets had become porous, soft and swelled up. I am trying to figure what could have caused that? I would think it rather become carbonized as the rest of the heads did? Weird eh?


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