Picked up a 87 Ranger with a miss. One cylinder was down to about 85 psi. All others 120-130. Figure that is where my miss is. Anyway. My son and I just tore it down. The land between ring one and two on the piston in the low compression cylinder had a piece that fell out when we removed it. All other pistons look good. Anyone ever just replace one piston rather that replacing the whole set?

The engine has been rebuilt once. The crank is .010 under and the bores are .060 over now. Everything measures good, so a polish on the crank and a fresh hone on the cylinders and it will be good to go. We are going to put bearings and rings in it.

It has the non-roller cam in it. Some of the cam lobes look like they are worn a little. The followers have a shollow groove where the base circle of the cam has been running on it. How worn is too worn to be reusable?

Hope someone can help out here.

Steve

 

Generally you're allowed a few thousandths of wear, but I replace them if you can feel the ridge on the follower or if there is any sort of scoring on the cam lobes. You can replace followers by themselves, and you have to replace them when you replace the cam.

 

I kind of thought that about changing the cam and followers together. It seemed like it should be like changing a flat tappet cam in a pushrod engine. Have to use new cam with new lifters. Thanks for the advice.

Steve

 

You can likely get a set of roller followers and a cam for not much more than standard. Might be used, but the rollers won't care if their bearings are good and the surface is not worn. I think the cam is a different grind to make up for the size difference of the roller followers, but don't take that to the bank. I saw a used set on craigs list for ~$50, if memory serves. I was tempted to get it, but really don't drive enough to worry about the followers and the Zinc diosulphate(whatever..) stuff that has been removed from most oil lately. When the Lima was first introduced, there was a problem with the followers, but that was then...
tom