I got a new Discovery from a friend for parts today. It's got a bad knock, sounds like a spun bearing or something. It doesn't overheat and has occasional misfires on 3. Any clue what the sound is from? I'm going to tear down the engine later. Just curious what y'all think.

https://www.youtube.com/watch?v=W5-n...ature=youtu.be

 

sounds like a misfire and maybe an exhaust leak

 

thats mechanical. Maybe a wrist pin or serious issue with the cam or lifters.

 

It's definitely mechanical. Sounds like it's coming from the bottom end but I could be wrong. There was some tiny metal flecks in the oil, but not much. Any other ideas?

 

hold it to the floor and see what happens

 

I'm sure it would blow to bits....

 

Double knock, probably a rod. I would guess big end but could be wrist pin. Don't start it anymore unless you just want to put a hole in the side of the case for fun. If you do blow it up on purpose, get it on video please lol.

 

Big end what I was thinking too, after listening to a bunch of videos. I'll make sure to get a video when I finish grabbing parts!

 

Lol, please do and give me an excuse to say

 

Sounds expensive unfortunately, IMO it's a big end 'death rattle' as it's too low pitched for a small end. IMO, start it up on tick over only but don't rev the engine it could go bang anytime and big time but use an engineers stethoscope to listen to the engine top and bottom and then switch off asap.

I sincerely hope I'm wrong for your sake.