Ford 8n engine rebuild

[David Fortier]

Hi, I did strip my 8N engine this week and plan to buy an overhaul
kit. I presently have thin wall sleeve in my block and plan to install
new thin wall sleeve(heard about the complexity of installing them,
but I will machine an insert on a lathe to help me out). I did some
research on the web about new sleeve and honing, but can't find
much info. Do I need to hone new sleeve after installing them?

 

[Duallie]

I had to hone mine to size. The sleeve I tried to freeze in dry ice and pound in took a lot more honing than the last three, those I pulled in slowly with all thread. I had a mandrel made from a cylinder of 3.25" rod. They were thin wall in a 9N.

 

[Britcheflee]

I did not - and have not heard it is required - make sure you keep everything in the same order they come out - be very organized and clean and take pictures of everything and mark with sharpie - the process takes time but I did it and if you are methodical it is not a difficult process - this was a few years ago now and someone here provided me with a fantastic step by step list which I followed and it worked out fine - I will search my archives and see if I can find it for you.

lee

 

[Britcheflee]

Ok I found it - rather long so if you want to e mail me then I can send it as an attachment to you - it is very useful
PM me with your e mail and I will send it to you

lee

 

[HCooke]

Here's a link to a web site with a great tutorial on rebuilding that engine.
http://www.external_link.com/

 

[ZANE]

Do not try to peel out the sleeves if they are cast iron. There is a process that can be used to peel the .040 steel sleeves by starting a screwdriver sharpened to one side to start the sleeve peeling . If this is tried on the cast iron sleeve I just about guarentee a broken block.

Their is a tool that you can use to drive the sleeves out of the bore with. It is best to have the crankshaft removed to insure that you don't damage the journals by striking them. You could have a machine shop fabricate one by turning a piece of round stock just a little larger than the bore of the cylinders. First turn a piece of stock of about 3/4" to about .020" smaller than the bore, then turn half of the blank to about .020" smaller than the bore of the sleeves. Cut about 3/4" from each side of the turned driver so that it will go into the bottom of the sleeve if the crankshaft is still in the engine and with a 10 or 12 lb hammer and a large drift against the tool drive them out the top of the cylinder. Or you can do it the hard way and fabricate a threaded thingy to straddle the top of the cylinder and use it to crank the sleeve out. Not recommended by me!

If it is the thin cast iron .040 sleeve the best way to remove them is to use a cutting torch or heating torch to heat a portion of the sleeve from top to bottom red hot and then allow to cool to room temperature and then the sleeve will almost fall out. This will not damage the cylinder wall as long as you don’t cut through the sleeve and heat the cylinder wall.

If you are a pretty good welder their is an easier way to get the old sleeves out. Lay the block on it's side and with a 6011 1/8" rod run a cold bead from the bottom of each sleeve to the top. Do this about 3 times in each sleeve and allow them to cool to the touch. You can then either pull them out with your hand or catch the bottom edge with a large screwdriver and tap them out. Be careful not to weld through the old sleeve. After you get the old sleeves out lightly hone or sand the bore where the heat from the welding may have cooked the carbon to the bore slightly. Don't hone much. The new sleeves must have an interference fit.

Don't try to drive the new sleeves in with the tool that you fabricated to pull them out with as that tool will split the sleeves when you try to drive them back in.

You can take a piece of flat plate of at least 1/2" thick and that will completely cover the top of the new sleeve plus about 1" or so and drive the new sleeves down till they are even with the deck of the block You will know when they are even with the deck because they won’t go any farther. You can make a better tool to drive the new sleeves by finding an old automobile rear axle that has a flange with the lugs. Drive out the lugs and cut the axle shaft off about 16” long and use it to drive the sleeves home. Works great!

I have recently found a good way to quick freeze the new sleeves that really speeds installation.
I bought a fitting to use to refill the small blue propane cylinders sold to use on a torch etc. Now I put the fitting on the BBQ propane bottle, turn it upside down and hold the new sleeve opening under the propane flow when the valve is turned on. I wrap the sleeve with a heavy cloth such as a towel and close the bottom of the sleeve with the cloth and around it. It only takes a few seconds of that liquid propane to freeze it solid. Then quickly start it in the bore and drive it down quickly. Most of the time the sleeve will almost fall down into the bore.

Be absolutely sure there is no source or ignition anywhere near when doing this and do it outside for sure.

Zane