Main bearing troubles
 

i had my dad listen to my engine, which had a tapping noise coming out of the left side. i was thinking it was an exhaust leak, but my dad says the main bearings are going out. do main bearings cause any kind of tapping that speeds up with the RPM of the engine, and slows down with the RPM? he also says it dissapears once i rev up, but you hear it in a 2000 RPM idle, and when the engine is settling down after a high rev. the engine has 147000 miles on it, i drive 15 miles to and from work on a freeway every day.


any information for me?

if you have a 5 speed i suggest a throwout bearing...

yeah.. that's not going to make a tapping sound. More like a squeal but nice try.

You've more likely lost a rod bearing but the damage is the same. Crank needs polished or maybe turned. Need new crank and rod bearings and new fasteners. Be really really happy if you don't end up with a full rebuild though I'd do one anyway. Consider swapping in a replacement engine. that one's gunna be spendy to fix.

that doesn't sound encouraging. although, gives me an excuse to do a 4.6 liter swap...

if its a manual and you've had the clutch replaced before i'd look at the TOB, definetly makes a tapping noise if the bearing touches the fork when the clutch is fully out...which is a common problem in those years. mine defienetly(sp?) taps. only problem is I need a firewall adjuster and idk if i wanna go through the trouble, its just a noise atm, and i know they can be quite loud.

new car swap IMO.

start by pulling your oil filter. Cut open the filter and check for flecks of metal. After that pull the tranny and check the TOB install (possible damage or marks to the TOB or clutch fork. Something will show contact marks.

it's an automatic. XD and i will let you guys know about the oil filter when i pull it.

EDIT: i had an engine stethescope for my engine, and my master mechanic (dad) said it was the cam bearings that were the loudest, because he heard it in the top half of the engine, and it got quiet at the bottom half. so, i have an excuse to get the powerpak from Super Six. :)

EDIT2: my dad is deaf...i brought it to a family friend who is a mechanic shop owner...he said it was most likely either my main bearings or rods. it's awesome, because if it is the rods, it's gonna be expensive to replace...yay...