Plz help ID strange sound coming from the front of the engine of '88 LXi.

[vetski179]

YouTube sample of sound.

Car is high mileage LXi. The sound is coming from the front of the engine.

Sound increases with engine RPM. Disregard where the video was shot. The video was to get the sound only. If I could narrow a location the sound seems to be coming from the water pump area.
The prime suspects are:
1: Water Pump (relatively new, no leaks, pump shaft solid, not wobbling as you'd suspect if internal bearings were bad. Seems too loud to be the water pump.)
2: Bearing in the timing belt tensioner.
3: Oil pump.
Minor suspect:
1: Alternator (relatively new, no charging issues)

I took off valve cover. No issues there. Removed top of timing belt cover and looked down into the belt tensioner area. Nothing obvious like metal shavings. Put valve cover back on, with top timing belt cover off and ran the engine. No wobbling of the tensioner pulley, and the sound was not louder. Sound is getting progressively worse over the last 2 months.

Thank you.

[ShiRen]

When was your last timing belt job? I would highly suggest you just do it and do the water pump (unless its clearly good as new) while you're in there. Its like less than a $100 job and is much cheaper and easier than if you were to wait for the timing tensioner to seize, bending all your valves or water pump going and overheating and blowing the head gasket. My money is on the tensioner because if it were a water pump there would likely be a geyser of coolant spraying in every direction, its easy enough to take the belt loose and turn it by hand anyway. In fact, you can run the car without the serpentine belts and narrow this down by a lot. Oil pump is probably unlikely, but not impossible.

If the tensioner is suspect you seriously do now want to be running or driving this car right now.

[Willo]

Sounds more like a connecting rod bearing?

[conozo]

Get a mechanics stethoscope and poke around, you'll pinpoint the loudest area real quick.

[vetski179]

I got a new timing belt/tensioner and water pump. Turned out to be the water pump. Thanks for all the great suggestions

[Oldblueaccord]

I got a new timing belt/tensioner and water pump. Turned out to be the water pump. Thanks for all the great suggestions

Thanks for the update and glad its fixed.