Ridge Reaming

[rae61]

I just started stripping down a 200 from a 65 mustang ( it's going in my 71 Bronco).

After I cleaned the carbon from around the top of the cylinders there is a small ridge in the top, all the walls look good no scouring,
nice and smooth. What are the benefits to removing the ridge, if I don't what problems will that cause? The bottom end looks good,
no machining required, so I'm thinking of doing just rings and bearings.

 

[rbohm]

8) taking the ridge from the top of the cylinders makes it easy to remove the pistons from the top. if you dont remove it you can severely damage the pistons and/or the block itself. this is the tool i use to ream the ridges, its not cheap, but it is easy to use;

http://www.napaonline.com/Search/Detail ... 0006403815

 

[Thad]

If you go back with file to fit rings besure to check end gap at the tightest point in the cylinders.

 

[mustang6]

Almost by definition, if you have a ridge your bottom end is not good to re-ring without boring.

 

[JackFish]

If you've never done it before it's easy to cut the cylinder out of round, which will subsequently call for truing up the bore at the machine shop anyways.
my machinist> <me

 

[rbohm]

If you've never done it before it's easy to cut the cylinder out of round, which will subsequently call for truing up the bore at the machine shop anyways.
my machinist> <me

8) i agree to a point. the tool i linked to however makes it easier to keep from making mistakes like that. i have used the old style ridge reamers, and the one i linked to, and the newer one is easy to use, even for an rookie.

 

[rae61]

Almost by definition, if you have a ridge your bottom end is not good to re-ring without boring.

I just want to make sure I understand, if there is any ridge I should bore the cylinders and I'm wasting money by just putting rings in?

I also understand that you can do damage if not careful with the reamer but the newer ones are a little more user friendly.

 

[rbohm]

Almost by definition, if you have a ridge your bottom end is not good to re-ring without boring.

I just want to make sure I understand, if there is any ridge I should bore the cylinders and I'm wasting money by just putting rings in?

I also understand that you can do damage if not careful with the reamer but the newer ones are a little more user friendly.

8) i agree with scott to a point. i have reringed engines without boring them, even though there was a ridge at the top, with no issues. granted boring a cylinder with a ridge is the best way to go, depending on your budget.

 

[64falconsix]

If you do not cut the ridge on a re ring job you risk breaking the top ring when you run the engine. the top ring could bind when it hits the ridge, I have seen this happen. I would have a machine shop mic the bore for taper and out of round.also check piston to bore clearence,and piston wear most machine shops will do this at no charge. If all are within specs, cut the ridge and put the new rings in. If it is in the budget boreing it out to the next useable piston size would be the best and longest lasting option.Also