when my winter beater (lincoln tc 1986 5.0) idles with the hood up i hear a sound that im not sure if its detonation or a rod knocking. i added a can of engine restor to see if that lubes it to reduce the sound...
how do i know which prob it is
rod knock is a worn bearing, what is detonation and how do you fix it? what doe they sound like?

 

Run the tank dry and put in a gallon of race gas or some gas with really high octane. If it knocks, that is not detonation. Drain the oil and put in 40 wt oil and a can of STP. If it quietens down, you have rod knock.

 

How do you fix rod knock permanently, besides running heavier oil? I own a thirdgen. I'm sure I'm going to need to know this.


And what's the sound difference between a rod knock and lifter noise.

Thanks.

 

Replace the motor or rebuild it.

 

Easy, R&R engine and rebuild it.

difference

 

or just change the rod bearings

 

If I am that far, I might as well change everything before I have to do it again. Cheaper to do it all once than to do it again.

 

not really. You don't even have to pull out the engine or disconnect the tranny to change the rod bearings. Just jack up the engine a few inches and drop the oil pan

 

You sure that the cam bearings and the cylinder bores don't need to be refreshed? I mean, if one set are worn out, could the others be that far behind?

OK. For the winter beater, I would just change the rod bearings like mentioned but if it was the other question where you are looking to fix up the car, I would refresh the engine if I was keeping it and it wasn't a winter beater.

 

Don't forget the oil pump. Get a high volume but not high pressure one.