main bearing noise

mcgill · Post by **mcgill** » Wed Feb 29, 2012 2:21 pm

hello ive just come back from a view of a rover p5b which is really on the ball,However"owning rv8s for 30 years "this one has a strange knock that hides behind the firing so to speak under load.sounds deep like big ends,but not the familiar patern...So has left me to think crank mains?....but as ive never heard a v8 with main problems,im stuck to guess what it is.
Rev the nuts out of it in nautraul as its whisper quiet,only under load or really cold..,has great oil pressure hot or cold..
any ideas?

kiwicar · Post by **kiwicar** » Wed Feb 29, 2012 3:14 pm

Hi
Piston slap? worn out engine mount allowing contact with the side of the engine bay causing a rattle. Flexplate/Flywheel comming loose?
Mains can go, on an engine as low tune as the rover you can have the crank fall in half at the centre main and only get a rattle as you go from load to over run otherwise no symptoms. Best advice I can think of is to drop the sump and have a look.
While I'm thinking of possable causes, the damper may have perrished rubber and be moving more than it should under load, fine off load and reved.
Best regards
Mike

mcgill · Post by **mcgill** » Wed Feb 29, 2012 11:07 pm

kiwicar wrote:Hi
Piston slap? worn out engine mount allowing contact with the side of the engine bay causing a rattle. Flexplate/Flywheel comming loose?
Mains can go, on an engine as low tune as the rover you can have the crank fall in half at the centre main and only get a rattle as you go from load to over run otherwise no symptoms. Best advice I can think of is to drop the sump and have a look.
While I'm thinking of possable causes, the damper may have perrished rubber and be moving more than it should under load, fine off load and reved.
Best regards
Mike

Ill go back to him,and see what i can sort out.i liked it as it has every bit of history and two owners,62,000 and all mots even original bill of sale,
thanks for the pointers

kiwicar · Post by **kiwicar** » Thu Mar 01, 2012 10:24 am

Hi
You have checked the exhaust manifold and system for leaks? just when they are from close to the engine they can sound very "metallic", normally miss identified as tappet noise though.
Best regards
Mike

mcgill · Post by **mcgill** » Mon Mar 05, 2012 9:36 am

Ive recorded the sound,,bit tinny but from phone and stuck on youtube,help appriciated....its the clattering noise after first ten seconds
http://www.youtube.com/watch?v=5mv99Uxs5L0