stumpedby weird noise from engine!
01-24-2013, 06:19 PM
#1
Member
Thread Starter
stumpedby weird noise from engine!
So I have a 91 190E mercedes 2.3 8v 5 speed. 194k miles. There is a noise that started out like a marble in a glass jar from around the alternator/water pump area on the front of the engine (I thought it was an alternator bearing going out). The noise is not there on cold start, only when it is up to temp. The noise has gotten deeper and louder and does not increase in speed with the rpms. It actually goes away when you open the throttle. (Or it use to). Now it is still rattling like a marble in a glass jar with a diesel type of noise from within the engine. When the car is turned off hot and restarted sometimes there is a loud metallic crunch noise as it turns over (engine mounts and tranny mount were replaced less then 2k miles ago). I have no idea what this noise could be and I can not seem to figure out if its the water pump, timing chain tensioner, timing chain its self, or some other problem. Car gets up and goes no problem, but I have had it stall out while idling at a stop light or even going around a corner at low speed (with the clutch depressed). And the idle will sometimes stick at 2k rpm but if I pull the gas pedal out it will down idle so I do not think that is related to the noise in question, please help!
01-24-2013, 08:08 PM
#2
Sounds like water pump bearing to me. Look at the pulleys while it's idling, you should be able to see it wobbling, later it'll actually spray water from behind the pulley.
Things like cam and crank bearings sound more like scraping metal when they go, it's the pulley bearings that sound like marbles. I'm not that familiar with clutch fans though, maybe it could be that too. Should be able to see/feel something loose.
Things like cam and crank bearings sound more like scraping metal when they go, it's the pulley bearings that sound like marbles. I'm not that familiar with clutch fans though, maybe it could be that too. Should be able to see/feel something loose.
01-24-2013, 10:58 PM
#3
Member
Thread Starter
Well there is the second deeper noise that would still be unaccounted for along with the metallic crunch noise on hot startup if it were just the water pump beaing. It can be heard inside the car with the windows up. (It kinda sounds like someone cracked a walnut made out of iron with in the engine when you start it right after turning it off when its above 80C).
