Noise after Timing belt replacement (1 Viewer)

[Usterzai]

Hi All,

I just changed the timing belt on my 99 LX with 17200 miles. Everything went smoothly but I must say it was exhausting especially those compressor bolts. It took me more than 2 hours to get them out. I read all the threads and basically watched clips of OTRAMS video while doing the belt. But now I have a problem.

There is this weird noise coming from the crank pulley area. It goes away when I rev the engine but I can hear it when parked or coasting on the highway. I removed the serpentine belt and started it and it looks like it is behind the crank pulley. I took a video clip and you can hear it at 38-42 seconds mark and around the 20 sec mark as well. Is this something of an immediate concern?


A friend of mine told me that the new belt might be really tight due to the tensioner being new and this noise will go away after sometime, is that true?

The timing marks aligned perfectly, and I checked them 10 times, the belt marks also aligned with the timing marks on crank and cams when I installed them. I also rotated the crank 2-3 times and it freely turned around. There are no leaks, no overheating, and the oil temp is in normal range, I have a slight missfire that was present before the belt job. I changed all the coils and plugs with Denso and I have been told that injectors might be the next culprit due to the misfires more prominent only on cold starts.

Help will be appreciated since I am planning to take my kids on a trip for new years.

FYI the old belt was in good shape but I found a lot of belt dust under the covers and the tensioner pulley was bad, as well as the fan bracket. So I am glad I changed it and hoping I wont have to tear it apart.

 

[fjcruising]

It almost sounds like the teeth of the belt haven’t been worn in yet and are rubbing every time they go around - which also is consistent with what your friend said. I’ve never heard that before so I’ll let others chime in but in my non expert opinion, it sounds plausible.

 

[KenH]

aftermarket belt? Asin tb kit = high pitch noise. I only do tb with oem only.

 

[2001LC]

I've never listen to belt after install on a 2UZ. I have on other engine where belt tension is manually set (no hydraulic tensioner) with feeler gauge. When set to tight, sound similar. But that's the beauty of the hydraulic tensioner, it's self-adjusting. If you used the OEM or the OE Aisin kit from reputable source like @cruiseroutfit . You should have all good parts. Like the NTN tensioner

I have noticed, some Amazon seller substituting parts. I'll except KOYO or NSK bearings.

Mitsuboshi is a OE belt. Replacement OEM Toyota belt have NBR made in USA on them.

VVT engine here, but marks are the same in non VVT.
Provided timing marks lined up after two full revolution ("T" is not timing mark). Yellow arrow points to timing mark.

If you replaced the crankshaft oil seal, and seal not seated flush with oil pump case. Crank sprocket may ride on seal and make this sound.

Crankshaft position sensor plate, installed cup side out, so it does not ride on belt. I would think, sensor would not read and you'd have cranking but no start. But if plate bent out, it may start. One way to check if not sure. Pull PS (easiest) belt cover and inspect belt. If plate installed backward, then new belt will be frayed on outside edge from rubbing of plate.

Also make sure coolant level is to top of radiator after 8 hour cool down with front end higher than rear of vehicle (best). Low coolant and pump runs dry and may make that sound.

Also, it's very important the thermostat jiggle value is at top. System will not bleed properly. When cooling system running properly. You'll have idling temp around 184 to 187 F. An easy check is turn cabin heat to hot fan on high. It should feel very hot at vent, but not excessive. If cool, coolant is not circulating, so likely low on coolant. Don't go just by what the gauge on dash indicates, until it's verified.

 

[Usterzai]

@210

I've never listen to belt after install on a 2UZ. I have on other engine where belt tension is manually set (no hydraulic tensioner) with feeler gauge. When set to tight, sound similar. But that's the beauty of the hydraulic tensioner, it's self-adjusting. If you used the OEM or the OE Aisin kit from reputable source like @cruiseroutfit . You should have all good parts. Like the NTN tensionerView attachment 2165543
I have noticed, some Amazon seller substituting parts. I'll except KOYO or NSK bearings.
View attachment 2165545
Mitsuboshi is a OE belt. Replacement OEM Toyota belt have NBR made in USA on them.
View attachment 2165547
VVT engine here, but marks are the same in non VVT.
Provided timing marks lined up after two full revolution ("T" is not timing mark). Yellow arrow points to timing mark.
View attachment 2165539

If you replaced the crankshaft oil seal, and seal not seated flush with oil pump case. Crank sprocket may ride on seal and make this sound.

Crankshaft position sensor plate, installed cup side out, so it does not ride on belt. I would think, sensor would not read and you'd have cranking but no start. But if plate bent out, it may start. One way to check if not sure. Pull PS (easiest) belt cover and inspect belt. If plate installed backward, then new belt will be frayed on outside edge from rubbing of plate.
View attachment 2165538

Also make sure coolant level is to top of radiator after 8 hour cool down with front end higher than rear of vehicle (best). Low coolant and pump runs dry and may make that sound.

Also, it's very important the thermostat jiggle value is at top. System will not bleed properly. When cooling system running properly. You'll have idling temp around 184 to 187 F. An easy check is turn cabin heat to hot fan on high. It should feel very hot at vent, but not excessive. If cool, coolant is not circulating, so likely low on coolant. Don't go just by what the gauge on dash indicates, until it's verified.

I did all the mentioned above things when installing the belts, I also downloaded the FSM timing belt parts from TIS website by subscribing for 2 days. The timing marks did indeed match up and I made sure of that by asking two other people two confirm both times when taking off and when putting back in.
I did order from amazon by following the link in otrams video to give him some credit for making a really good video. The tensioner was NTN, bearings were koyo and NSK, and the timing was belt Mitsuboshi. The only thing I noticed was the finish of the water pump was a little rough. The kit was sold by amazon which I made sure cause I had bad xp with 3rd party sellers on amazon.
I was going to order parts from cruiser outfitter but I rent somebodies garage to do my work and he changed the dates on me so I had to go the amazon route to get the parts before the window of the garage availability closed.

I also took the air out of the cooling system which took a while and it is exactly like what you mentioned. The coolant was to the top in the radiator early morning after being parked with the top up.

I think the belt is rubbing with something but I am not sure what. I found evidence of rub on the old belt which was Toyota belt changed at 90000 miles by Lexus dealer. I placed the crank sensor like it should, is it possible that it was bent a by some one in past ? Is it easy to change out ?

 

[2001LC]

You've "@210" at top of post #5. I hope that not coolant temp?

Do you know if the worn side of belt was facing out away (front) from engine?
I've a few pictures of used belts, but only fronts & tops. They are not worm like your belt.

Here one that side of belt aren't visible clearly. In it I see rear appears it may be a bit frayed.

You need to pull lower cover to get at sensor plate, which everything is in the way. If your old belt is frayed at front, you may be able to see sensor plate and belt. I've not tired this; But, if crank sensor pulled, a small snake drain camera or mirror, and you may get a peak at senor plate. You can also use a snake camera from above. Just pulling the PS top cover you can see the belt, as I pictured above. Then run the snake camera down inside. I picked up a snake camera off Amazon for $30. Wifi to my iphone for viewing. Not great but usefully.

If engine running good with good temps, I not worry to much. Drive as much as you can now before the trip, pushing it hard. See how it acts.

Misfire: I'd look in tech stream at misfire, and load the engine (foot on brake and gas in transmission D) as you do. Miss may be fuel injectors, which 44k and Chevron Techron is helpful in cleaning them. Also watch your fuel trims for clues. Also look for vacuum leaks. The seals at bottom of injector can leak air as can intake gaskets, natural replace all old cracked hoses.

But don't make to much of engine sounds, misfire when cold. Cold does give clues, but operating temp is where we want all as it should be.

 

[Usterzai]

I think I was writing @2001LC but some how one zero got omitted. The cooling temps with the scan gauge are at 182-186. 186 when I floored it and it goes down in couple of seconds to 181-182. The temperatures dropped by 10 degrees after the belt change. Before I had 191-194.
I took some pictures before the install and the worn side is in the front. The marks are visible on the PS cam pulley.
The snake camera is a great idea and I will try that. I do have one but it can be used with laptops only. I used to check CATs and what I found was not good PS side honey comb 70% blocked but I am getting a code for driver side. Strange but a problem for another time .
I will check the techstream tomorrow to check for fuel trims. The intake gaskets are all new I changed them when the starter failed, hoses are on my list, I have changed the PCV hose so far with the PCV valve.

These are the pictures I have pre belt removal, the marks are visible on the front of the belt. I should mention that I did not remove my belt at the position in the picture I went 50 degrees ahead just like FSM said. I don't have after pictures because I was on Face time with a friend showing him timing marks to confirm when I dropped my phone in the coolant bucket under the engine.

 

[2001LC]

I can think of only 3 points the belt is touched at front; water pump pulley, LH cam sprocket and crank sprocket sensor plate.

The above picture resolution is to low, and I can't zoom in. So I can't see.
But old belt was frayed on front. Then one possibility is crank sensor plate was/is somehow bent.
The crank pulley holding tool commonly sold, has bolts included that are to long. If bolts not shimmed out, the bolt run in to far and can damage the plastic cover. This could also bend the sensor plate. In that case you would have seen marks on lower cover.
Someone may have torqued down the crank bolt, with sensor plate on backward. Then subsequent corrected, reinstalled damaged sensor plate. Bent sensor plate could give a slightly erroneous signal to the ECM by way of crank position sensor, effecting timing just a hair. Timing can affect temp.

Your temp being at 191 F pre belt may be clue.
Assuming you had good coolant mix and topped, new plugs & coils in and saw those temp pre belt job.. basically did only the belt job then saw temps drop. Then your water pump may have been going bad. Typically the bearing goes bad and leaks at same time. This could damage belt on front, if WP pulley just a bit misaligned due to bad bearing. So if new belt not frayed, it's point to water pump frayed old.

If new belt frayed, points to crank sensor plate.

Or my thinking is a holiday mess. Merry Christmas!

 

[Usterzai]

I can think of only 3 points the belt is touched at front; water pump pulley, LH cam sprocket and crank sprocket sensor plate.

The above picture resolution is to low, and I can't zoom in. So I can't see.
But old belt was frayed on front. Then one possibility is crank sensor plate was/is somehow bent.
The crank pulley holding tool commonly sold, has bolts included that are to long. If bolts not shimmed out, the bolt run in to far and can damage the plastic cover. This could also bend the sensor plate. In that case you would have seen marks on lower cover.
Someone may have torqued down the crank bolt, with sensor plate on backward. Then subsequent corrected, reinstalled damaged sensor plate. Bent sensor plate could give a slightly erroneous signal to the ECM by way of crank position sensor, effecting timing just a hair. Timing can affect temp.

Your temp being at 191 F pre belt may be clue.
Assuming you had good coolant mix and topped, new plugs & coils in and saw those temp pre belt job.. basically did only the belt job then saw temps drop. Then your water pump may have been going bad. Typically the bearing goes bad and leaks at same time. This could damage belt on front, if WP pulley just a bit misaligned due to bad bearing. So if new belt not frayed, it's point to water pump frayed old.

If new belt frayed, points to crank sensor plate.

Or my thinking is a holiday mess. Merry Christmas!

I like your thinking and tomorrow I am going to use the snake camera to try to get some pictures from the passenger side belt cover. I appreciate your help I was stressed out but feel much better now .
Prebelt I had installed new plugs 10000 miles ago and 8 new denso coils - 1 month ago, also torqued the plugs when changing coils after I read your thread about them coming loose. Some were a little loose so Thank U for that as well.
I am going yo try to upload pictures again maybe that works.
Merry Christmas.

 

[Usterzai]

Just snaked a camera through the passenger timing cover and it does not look like the belt is rubbing against the crank pulley. I do see a slight mark on the new belt but I am not to sure where it is rubbing. I am going to drive it from some time and will report back hopefully it will go away with time.

 

[Rick Stevens]

Hello sir, I was searching for some info for this EXACT noise from my 2UZ engine and ran across this post. It started right after I installed the aisin timing belt kit . Was wondering if you would be kind enough to share the final outcome. This is my wife's daily driver and I'm now worried about reliability. Sorry to ask a question as my first post here , but my son has several scheduled doctors appointments through the end of the year that are quite a ways from home. I won't be able to go with them most of the time and I'm running out of time on this repair. Any insight would be greatly appreciated.

 

[Usterzai]

Hi, the final outcome was that it was normal. I believe when we change stuff we kind of get more sensitive to different noises. I drove mine 10k miles with no problems. I am not sure how your sounds like but I think the culprit might be the belt. However, I am no expert either so I cannot say it is normal. I took mine to Lexus check and they also said it was normal and nothing unusual. They also did not charge me anything which was nice of them. I now have 04 LC and this time I plan on using OEM belt not the one that comes with the kit.

 

[Rick Stevens]

Thank you very much! Mine sounds exactly like your video. Perhaps I am being hyper sensitive. I just need it to be a reliable as possible right now and was a little freaked out when I heard the noise. Again, thank you !

 

[mtlexus]

I don't mean to bump/necro an old thread - but this is the ONLY example of this sound I can find. The EXACT same thing is happening to my GX470 after a timing belt replacement. It does not sound normal, but was hoping anyone else could chime in on whether they've heard this after a belt change and what ended up happening.

 

[Mike NXP]

I don't mean to bump/necro an old thread - but this is the ONLY example of this sound I can find. The EXACT same thing is happening to my GX470 after a timing belt replacement. It does not sound normal, but was hoping anyone else could chime in on whether they've heard this after a belt change and what ended up happening.

I just read through this and watched the original video and I personally would cast a vote for 'not normal' ...Now that may not necessarily mean there is an immediate problem but something sounds out of round / rubbing / worn / different than other 2UZs that I've heard......Video / audio online can be deceiving though...... Since OP mentioned he's gone 10K+ with the noise maybe it's not anything to lose sleep over

How tuned in to your motor were you before the timing belt install? As noted some folks just tend to hear things differently once they start paying attention. However, if you are pretty well aware of how your motor usually sounds, and it sounds different right after the timing belt job, I can't help but think something changed.


Welcome to MUD...Looks like you're down in Helena? Consider bumping over to the MT406 clubhouse and see if there are any cruiser folks in your area who can have a listen. If you're up in the Kalispell area, I've got a 470 you can listen in on to compare

 

[mtlexus]

I just read through this and watched the original video and I personally would cast a vote for 'not normal' ...Now that may not necessarily mean there is an immediate problem but something sounds out of round / rubbing / worn / different than other 2UZs that I've heard......Video / audio online can be deceiving though...... Since OP mentioned he's gone 10K+ with the noise maybe it's not anything to lose sleep over

How tuned in to your motor were you before the timing belt install? As noted some folks just tend to hear things differently once they start paying attention. However, if you are pretty well aware of how your motor usually sounds, and it sounds different right after the timing belt job, I can't help but think something changed.


Welcome to MUD...Looks like you're down in Helena? Consider bumping over to the MT406 clubhouse and see if there are any cruiser folks in your area who can have a listen. If you're up in the Kalispell area, I've got a 470 you can listen in on to compare

Thanks - I’m going to drive it for a bit to see what happens. Not feeling super hopeful since I’ve put 100 miles on it with no change yet, but you never know. The shop has said they’ll look at it again if the noise doesn’t subside.

And thanks for the welcome. I’ll definitely check that out and I just might take you up on that offer next time the wife and I are in Kalispell. Cheers.