You may need to change a damaged guide, or need to remove all of them to have the bottom of the block machined flat.

Drifting them out will not be easy, two sides of the guide are very thin and damage easily.

I am not aware that new replacements have ever been available, but luckily they are usually in really good condition, plus there are plenty of scrap blocks around and always worth keeping a set of guides on the shelf, if you are scrapping a cracked block.

Image 1

This is a piece of 1 1/2″ OD tube with a flat filed to clear the adjacent guide, a long 5/16″ bolt or threaded rod, and a 7/8″ long spacer with a diameter just under the size of the guide. Mine is made from aluminium so as not to damage the guide.

I made the top washer from 1/4″ steel plate, so nice and strong. My tube is 2 3/4″ long with the bolt 5 1/2″ long but both could be an inch shorter as you only need to lift the guide 1″ to free it.

Image 2

Photo 2 shows assembly ready to pull the guide up flush with the block (about 3/16″), remove the nut and then fit the 7/8″spacer and continue to pull the guide up until free.

Image 3

Guides can be refitted by carefully using a hammer and hardwood block, fitting as pairs with flats together will save alignment problems if done singly.

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