So during a checkup my mechanic found a small ticking sound coming from the water pump area, so I asked them to open stuff up and check it out, and replace drive belts etc. since my car has almost 90k miles. I was initially told it might be the water pump, and I was quite surprised because I believe the 2011 shouldnt have any water pump issue. Turns out it's not the water pump, but an oil scavenging pump that has a failing bearing so it has a bit of ticking sound. The part for this pump cost 3x more than the water pump. I did a quick search on the forum and did not find any posts on this. Dont know much about the pump other than it pumps engine oil trying to behave like a dry sump engine. Just wanted to share with everyone here.

 

Part number is 151A038010, same as the one in RC F

 

Engine has 2 oil pumps, which one is it?

 

The one on the serpentine belt drive. The main one is driven by the crank and lives in the timing chain cover. When you say ticking noise, did it make the noise all the time or only hot/cold? Mine still makes a really annoying ticking noise when cold and it really sounds like it could be coming from the scavenging oil pump. It also gets louder when I remove the oil fill cap, making me think the origin of the ticking isn't external like the broken exhaust manifold crowd, and the noise is very random which makes me really doubt it is valve related because valve noises don't go away with warming up, and they're like clockwork, not random.

Did you happen to shoot any video of it making the noise before you took it to Lexus for examination?

 

No I didnt get a chance to take a video, i should have....it grew louder so i was hoping to get to the mechanic in time before anything blows up...

the sound is present all the time...start up, throttle, ac...its frequency seems to correlate to engine rpm

 

That sounds normal, all Fs tick and it does correlate with RPMs. Unless this is a different/new ticking noise I would be skeptical.

 

Yeah my description is probably off. It starts with the tick and gets into a grinding sound in under 30 minutes...u can hear it loud and clear inside the car with windows closed at the end of 30 min..
definitely not a normal sound...not sure how to describe it

 

Yeah grinding is not normal, thats a nice list of cars in your sig btw.

 

A lot of Fs tick - Mine does not and it never has.

Lou

 

It happens really quick though..from a slight ticking that sounds like a louder normal belt drive or the injector sounds...to a grinding one (kinda like a pebble rolling inside a pump) in under 30 min..i was genuinely worried. This car has been solid reliable otherwise, not a hiccup

well i am glad it's not the water pump so it is true it doesnt affect 2010+ models

 

So just to update everyone on this..it appears to be a false alarm, in a way
I had to wait a few days for the scavenging pump to come in (back order part). After taking apart everything, they found it's not the water pump or the scavenging pump, they suspect it's engine oil related. I found that hard to believe because the oil was changed with Kennol synthetic about 1000 miles ago at a friend's shop...and how can engine oil cause noise in the oil pump?
So my mechanic is referring me to lexus after all that labor, and is not charging me anything. I want to pay my share for their time so I asked them to go ahead and change the oil and the drive belt, since parts were already taken apart.
After they changed the oil and drive belt the noise goes away. They did mention the oil filter was extremely dirty and doesnt look like it's replaced 1000 miles ago. Our guess is the previous shop forgot to replace the filter...and the pump couldnt get enough oil due to blockage or pressure etc. I am only glad I did not drive the car far after hearing the noise, hopefully no further damage was done.
I will keep checking in to see if the noise comes back, fingers crossed. But so far it just appears to be a really dirty oil filter. From the fact that the forum has no record of this part failing, and lexus dont carry the part anywhere means it's probably something that rarely breaks...
At the same time I am also freaking out coz the same shop changed the oil for my other cars...obviously i wont be going back to the "tuner" shop

 

^^^^Glad they figured it out for you and it was a false alarm Not changing the oil filter

Lou

 

My mechanic was changing the serpentine belt last week and notice that the scav pump bearing sounded a little rough slight grinding sound when spun.
If the bearing is bad can I simply change the bearing or do I have to change the entire scavenging pump?
Also has anyone had a similar problem?

MY08 Japan spec.

 

Haven't heard of this failure on this forum. TIS doesn't give any help for the internals of the scavenge pump, so you're pretty much on your own if you just want to replace a bearing. Keep in mind, you have to remove the timing cover to do this job, so it's no small task. It appears there are metal tubes on the backside of the timing cover connecting to the scavenge pump that must come off to remove the pump. So, you might want to save yourself a lot of grief and just buy the new pump. It would really suck to remove the timing cover, "fix" the pump, and then have it fail shortly after putting the whole front of the engine together again.

BTW, this pump must be made of Vibranium or something. I'm seeing a little over $500 from US Lexus discount retailers.

 

Thanks for this, I'll do some more research on it maybe it's a similar case at the OP.
I'd rather spend that cash on some new rear bushings