Nimajneb

I was wondering if anyone could help me figure out what might be wrong with my 1991 Lexus ls400... A couple weeks ago i noticed a loud whining noise coming from my engine... I happened to notice it right before I noticed my car started to overheat... I let my car cool down while checking my fluids and everything seemed fine... I drove it home later that night... The next morning on my way to work I heard the same loud high pitch whining noise (Similar to a whining belt)... Since I was at work and not far from home I decided to drive it home after work... The noise was still there but this time I noticed a little smoke coming from the engine when I got home... It smelt like burnt oil... I let the car sit for a week or so until I had the time to try to fix it and figure out what was wrong... I know it isn't the serpentine belt or anything attached to it.. They all move freely and the car still whines without the belt on...

So my thinking is maybe the bearings in the water pump are going bad? But on the way to the garage to work on it the whining noise suddenly wasn't there anymore... I thought maybe I got lucky and continued on with no whining for about a week...

Well now the whining is back and its starting to smoke a lot worse...

Any ideas? Any type of information would be extremely helpful as for I dont want to start ripping apart the engine to get into where the water pump is since its kinda tedious...

cobalt91

Smoke from the tail pipes or under the hood? How old is the timing belt? Any oil leaks around the front of the engine? Maybe oil getting on the timing belt.

steve2006

Overheating and the whining noise would suggest the water pump is shot, you do not say how many miles the car has done or whether the TB and WP have been changed.
There is no easy way of diagnosing the probem apart from stripping the engine down to physically check both, it may be tedious but if the pump bearing goes and the belt comes off you will have to do the job anyway.

RA40

iTrader: (6)

Welcome to Club Lexus. Not knowing the history on the car...

Mechanical components that emit noise is an ASAP issue to check. The overheating and the noise would indicate a water pump along with the cooling system maintenance. Since you have to open the front to get the water pump, might as well do the timing belt, idlers and front cam seals.

Nimajneb

There are 215k miles on the car... When I changed the fan bracket a couple months back I had the front all open and the timing belt looked like it had recently been changed.. Even my mechanic thought the same thing... In fact I had bought a timing belt in preparation to changing it while I was in there but seeing its condition I decided it didnt need done... I just recently purchased this car a year or so ago and am not sure on the service records...

I thought the same thing that it might be the water pump but the car doesnt always overheat... Only on long journeys.. I figured if there was no coolant going to the engine it would overheat extremely fast???

It appears the smoke is coming from under or below the LH timing belt cover... My concern is that if the water pump bearings are going that would make sense for the high pitch whining noise but I dont understand the smoke coming from under the LH timing cover? Especially cause it smells like oil not like two pieces of metal rubbing together...

I will start removing the front components of the engine this weekend and get to the point where I can remove the water pump... Hopefully I will find the problem along the way...

Can anyone tell me what turns the water pump? It doesnt appear to me that the serpentine belt runs it? Is it connected through the timing belt or is it propelled through the motion of the water? Just curious...


Thank you all for your speedy responses and suggestions... I am no mechanic but I consider myself pretty handy once I know what to go after.. My problem is I dont know enough about engines to diagnose these tricky issues.. So your help is very useful... Especially because I am a college kid and cant afford to take it to the dealer and pay $80/hr labor for some schmuck to rip apart my engine replacing everything in his path...

SkulCracka

lexls.com you will find what you need there. but honestly you think water makes a water pump move? so what makes the water move. i hope you typed that just not thinking.

RA40

iTrader: (6)

In light of that, probably separate issues:

Check between the A/C condenser and radiator for debris hindering airflow. If the cooling system has not been serviced, I would suggest doing that.

If there is burning oil that will be pretty obvious when you get in there to inspect WRT what needs to be replaced.