Made the mistake to try and replace my timing belt by watching a youtube video. I rotated the old belt till all 3 timing marks aligned. Removed the old belt, but while I was trying to install the new belt to the timing marks I noticed the rear camshaft had rotated about 45 degrees counterclockwise. I tried to move it clockwise but it behaves like it's spring loaded and moves in increments of 20-30 degrees at a time. At the moment it's about 30 degrees clockwise from the timing mark. I've done some research since then and I realize that I should had rotated the crankshaft about 50 degrees clockwise before removing the old belt. Does anyone have an idea on how I can rotated the camshaft back to the timing mark without damaging the engine?

 

You have to rotate the rear camshaft back into position carefully while keeping an iron grip on the wrench! It WILL stay in position, but just barely. You will have to rotate it again to get the new timing belt on. Again, keep an iron grip on the wrench!!! And use a wrench, not a ratchet. You need to be able to control it in both directions!

Another trick, DO NOT PULL THE PIN on the tensioner until AFTER you rotate the engine twice and double check the alignment.

Bob

 

This is true, the rear cam is on a cam lobe and will want to spring forward or backward very easily.

Using some small size spring clips like the ones sold at lowes works well for keeping the belt on the cam sprocket(see pic below).
Also, using "C" clamps holding the cam sprocket to the rear metal timing belt cover helps hold the cam gears in place(optional but I like it).

My technique starts with lining up the rear cam sprocket first, and then running the belt around the tensioner and crank.

Next I do the front cam but this is where the rear cam wants to spring forward/backward and this is where the "C" clamp comes in handy to hold the rear cam sprocket in place.

Now with the belt clipped onto the rear cam sprocket(see pic below) and a "c" clamp securing it from moving, I rotate front cam ccw one tooth and put the belt on and take the slack out between the cams and clip the belt onto the front cam sprocket and "C" clamp it securely and see how it lines up.

At this point the belt is clipped to both sprockets and both sprockets are clamped in place with slack removed between them.

Also, before pulling the pin on the tensioner I lastly turn the crank cw a tiny hair to move any slack between the front cam sprocket and crank towards the tensioner area so that the belt is snug all around and check all the marks again.

Then I pull the pin on the tensioner and rotate the engine 2 revolutions and check marks again;
Some people prefer to rotate the engine first before pulling the tensioner pin.

Agree with checking work by rotating everything but the cam lines printed on the belt will not line back up again after 2 engine rotations(fyi) but your cam sprocket lines and crank marks better line up or the engine will be out of time.

PS- I've had the rear cam snap forward and backward on me and it didn't cause any damage. When it happened I turned it back in the direction of the position it came from.

Good luck!

 

I been thinking bout this too onRX400H

https://pmmonline.co.uk/technical/ti...exus-rx-400-h/

I thought you had to lock and immobilise the cam and crank.

 

[QUOTE=Vincenze;11033791]I been thinking bout this too onRX400H

https://pmmonline.co.uk/technical/ti...exus-rx-400-h/

I would recommend this guy on eBay 'AirCabinMan' he's got like 1000's of + reviews and his kits are 100% real toyota parts. I paid like $215 for mine (04 RX330) and even bought the cam and crack seals afterwards from him.

Some people complain about Gates and goodyear belts being loud. Go orginal Toyota parts. Even though they are made different japanese companies Asain (wp) and Mitsobishi (tb) and others, he sells you legit stuff that came on your car.

Just a thought..
Sav

 

[QUOTE=Savnout;11034126]Totally agree on the OEM parts. If you do belt do WP to (belt and braces!!). That is a great link. Ta. I know it is do-able for the medium level mechanic going through the (in the UK) driver side wheel arch.