Ok I have a 72 351C that I rebuilt and have since day had a rattle in the upper part of the motor. a few years pass and it finally decides to chew up a lifter leaving the bottom half at a 45 degree angle and my cam lobe slightly rounded on the edges. so i tear down the motor and replace the cam and lifters knowing full well that there might be a chance of residue chewing the whole inside of my motor up, but I think I cleaned it out decent enough. anyway the problem is, it did it again. same lifter on cyl 3. not sure if its exhaust or intake. but what would cause this to happen? where does the lifters get there oil from? do I possibly have a plugged oil hole? any help is appreciated. thanks

 

The lifters are supplied by a gallery that extends the length of the block. If you pull out all the lifters on the same bank, and pull the plug at the front of the block you can see all the way through them.

Here's what you do to check for oil flow: Remove the intake and distributor and remove all the lifters on that side and line them up in order so that they can go back in the same bore when you're finished.

Put an oil primer shaft in place of the distributor and chuck up a drill. Run the drill and observe to see which bore the oil comes from. On a Windsor engine it would come from the rear lifter bore oil hole. I expect the same on the Cleveland but don't remember. When you see oil coming from the first bore in the line, which ever it is, put the correct lifter in that bore and run your oil pump again. If oil comes out of the second bore put the correct lifter in that bore.

Continue down the line making sure that you not only get oil from each bore, but also see if each lifter fits its bore preperly. If a lifter were loose in its bore, it could lose pressure around the lifter.

ALSO... are you running an oil with the zinc additive or using a cam break in supplement with the additive? If you don't provide the zinc additive on a new cam and lifters, you will have this problem although not usually on the same lifter bore. That said if one lifter were not getting oiled well, then the lack of zinc might show up the same place each time.

Make sure that there is nothing in that area that would restrict oil splash to that lobe. Splash is the only way that the lobes are lubed. That's why you run a fresh cam and lifters at 2000 RPM for 20 minutes during break in, to ensure there is plenty of splach.

One more thing. In the last few years the number of flat tappet lifter manufacturers has shrunk dramatically. This has caused some REALLY junky lifters to come in from China. Make sure you use quality lifters from Comp or Crane.

Hope this helps,

 

Thanks for the reply, I will try that. ya i am using the rotella diesel oil cause of the zinc factor and I knew the lifter market has shrank so this last time i bought motorsport lifters. i figured those would be good I know they were pretty expensive for lifters haha. the only thing I can figure is not enough oil to it. thanks again

 

I think that the MAIN thing you should check is to see if there is an obstruction to oil splash. It could be a piece of gasket material caught in a crucial position or something. I would remove the cam and probe around to make DARN SURE that nothing is restricting splash.