caskibum

Increasing valve noise after timing belt replacement on 2005 RX330.. Timing marks dead on, crank rotated 60 deg CCW per instructions before removing belt, front camshaft snapped back forward to TDC from lifter force on cam when timing belt was removed. I have found references to VVT-I variable timing sprocket being knocked out of whack or damaged from backward rotation or other mishandling.

Thread at link below describes similar situation, which was resolved by removal of exhaust camshaft and what is described as "reset of aux gears". I've found some info on "resetting" variable valve timing sprockets, but nothing pertaining to 3MZ-FE engine or specific enough to act on. I'll be opening the valve covers shortly to check clearances, hopefully nothing bent up.

Any info or insight on resetting the variable timing sprocket or engagement with the exhaust cam would be awesome. (fingers crossed for info and an easy fix).

Thanks for any help our suggestions.

Quote from thread: "It must have caused the VVTi to do something to cause that noise in spite of all the timing marks in place. I pulled the exhaust cams, reset the aux gears, replaced the hydraulic tensioner, and while I was under there (under where) fixed some exhaust problems and serviced the tranny. Fired it up and purrs like a kitten!"

https://www.clublexus.com/forums/rx-...ine-knock.html

Audiqv8

Did you use OEM parts or aftermarket?

https://www.clublexus.com/forums/sc4...lt-wp-kit.html

ukrkoz

Donno. I gave wife's RX300 to buddy's shop for belt replacement and two days later error light came up. Forgot which code exactly it was but it was one pointing at VVT-I malfunction. I called him, he took car back and fixed it. It was their fault, some minor thing, during belt install, as it runs on both VVT-I actuators. Sorry, t'was years ago, I forgot exact reason. But it was installation fault. I would not be trying to remedy it with resets, hence.

caskibum

Audiqv8, I used Aisin TKT-026 kit from Amazon. Came with Mitsuboshi belt, Koyo pulleys, and NTN tensioner. Interesting link on non OEM noise, looks like I have OEM parts as noted on your post in linked thread. Looking back the Amazon kit says "OEM equivalent" Mitsuboshi or Gates belt. I was pretty sure they specified OEM/Mitsuboshi when I ordered, I would have passed if I realized Gates was an option. There's a pretty big racket from under the front valve bank on my car with all accessory belts off, timing marks dead on,so I don't think it could be a pulley or belt issue. I have to assume some valves are jacked up or hopefully some VVTi mechanism is out of whack. I've done several timing belts before, two on similar toyota motors, and this went by the book with all marks spot on. Only issue was the front camshaft sprocket spinning back to TDC when the belt came off. The instructions in the Aisin kit said to rotate the camshaft CCW (backwards) to 60 deg before TDC to safe the valves from interference before removing the belt, which I did, and then the cam rotated when the belt came off. On reassembly, per instructions, I rotated the cam sprockets back to TDC, then the crankshaft, then installed timing belt. I've seen a few different instructions over the years on avoiding damage from cams spinning off compressed lobes during TB replacement, I don't recall this method on the prior VVT toyota motors I've done. I'm sick to think I might have jacked up the valves and need heads repaired when everything went be the book. If the front valves are jacked up from the cam spinning, I wonder if it would be appropriate to rework the front heads only since there was no motion on the rear cam and it's such a pain to get to? Anyhow, the prior post on cam spinning, loud valve clatter, and resolution by "resetting" VVT-i phaser pulley has my hopes up if I could understand what this is. Sounds like a job for moderator VVTiBob!

ukrkoz, No error codes, but this sounds similar and keeps my hopes up. I've had the VVT-i oil solenoids go bad and all the error codes, this is not my problem, not sure it would have been related to your belt replacement either.

Thanks both. Pulling the valve cover today and have my fingers crossed.

caskibum

Pulled the valve cover, all valve clearances in spec. Checked OBD and found error code P0018, had not thrown the check engine light. Checking the cam play and noticed a bit of backlash between the cam and the timing wheel pulley!!! The pulley bolt was not tight and the alignment notch in the pulley had been worn by the pin. Some metal filings inside the pulley and almost one tooth of backlash between the pulley and cam.

Positive I hit both pulley bolts with the torque wrench at 75 ft-lbs. The pulley torque tool has a pivoting arm and a couple bolts, I can only guess the torque wrench hung up on the pulley tool somehow and did not load up the bolt???

No pulleys in stock locally, arrives Tues.

Shaking my head a critical bolt came loose on my shift, but much relieved the problem is simple and solved.

As for the VVT-i "reset" or "unlocking" suggested, possibly resulting from camshaft spinning, I have not found any info to corroborate this (although there is much info on unlocking VVTi gears and replacing seals on the the 2AV-FE cam timing gear).

I'll sleep better tonight, and post back when running smooth again.

Felix

Just to add the 3mz uses solid lifters, vvt solenoilds on the intake only...which are on the drivers side of the intake....