Changing timing chain

[Hossam1516]

Hey, i have Toyota Avensis 2008, i'm planning to change the timing chain because it's make a lot of noise the car has 3ZZ-FE 1.6L engine and this is first time to do timing job but before i begin the job i did a lot of research about the timing and i saw a lot of videos and i know a lot of tips and tricks but i have a question; i saw in some forums that people had set the timing right and rotate the engine by hand and everything is good but since they started it up piston hits the valve and they are not able to rotate it, so my explanation on that from the experience i gathered from the internet and service manuals in any chain or belt system there's tension and slake side. The slake side always facing the tensioner, so in their situation the chain is already has slake in the tension side and by rotating the engine by hand doesn't make in trouble and since they stated it up the chain jump a tooth ? and also if i pretty sure that i'm in time and every inch of the chain in the tension side is very tight and the only side has the slake is the side that facing the tensioner so after release the tensioner it should be done and everything is good, Right?

so please anyone helps and please DON'T tell go to anyone professional to do it for you because i'm in very super budget at this situation, so anyone has experience in this job please tell me

[furtula]

How many miles does you Avensis have? Are you sure its not just the chain tensioner that needs to be replaced?

The purpose of the tensioner is to reduce the slack. I don't see how it's relevant anyway.

True, the chain wears out, but the number of links always stays the same. So if you have everything lined up, just wrap the chain around it, and the tensioner should do the rest, that is, reduce the slack.

The tensioner should be spring loaded, if same one as used in Auris, so once you set, and line everything up, you can release the tensioner (has a tiny mechanism to keep it closed), it will apply tension to the chain.  If you are afraid of pistons hitting the valves, remove the spark plugs, and turn the engine manually. If there is some interference, it will get stuck.

[Hossam1516]

34 minutes ago, furtula said:

How many miles does you Avensis have? Are you sure its not just the chain tensioner that needs to be replaced?

The purpose of the tensioner is to reduce the slack. I don't see how it's relevant anyway.

True, the chain wears out, but the number of links always stays the same. So if you have everything lined up, just wrap the chain around it, and the tensioner should do the rest, that is, reduce the slack.

The tensioner should be spring loaded, if same one as used in Auris, so once you set, and line everything up, you can release the tensioner (has a tiny mechanism to keep it closed), it will apply tension to the chain.  If you are afraid of pistons hitting the valves, remove the spark plugs, and turn the engine manually. If there is some interference, it will get stuck.

My Avensis has 218k miles and i will change the timing chain because over time it get stretched so i'm wondering about these people who done this job and as they said that they done the time right but when they start the engine everything goes wrong or just this people are lying and doesn't align the marks right ?

[Catlover]

Hi Hossam, it seems you have done your research well, read instructions and watched videos. You know the theory, now need to CAREFULLY put theory into practice. I suggest that is where others have gone wrong, they have not been careful enough. If you get the crankshaft and the camshaft teeth in the right position (get the manufacturers markers right place) then it should be ok. Just take your time, be careful, check your work carefully, you should be ok. Get it wrong, even by one tooth, then you will have problems. As Dean (furtula) says, take plugs out, revolve engine slowly by hand to check all is ok. It’s a long time since I done this job, principle is just the same, take your time, check and check again.            
Make sure you buy a quality chain, it does a lot of work, buy cheap and it may stretch more quickly.           
You will be buying a new filter and new engine oil, don’t buy the cheapest, buy quality filter and the correct grade of quality oil. Your car has done a lot of kilometres, treat it with respect and you will get many more hopefully.         
Change your engine filter/oil at least in line with Toyota recommendation, if not sooner. Look after the engine.                    
If the plugs and air filter have not been changed recently, maybe change then now. I know it’s all an expense, but it’s worth the effort to look after your car now, otherwise you will have a bigger expense sooner.            
Keep the form informed, let us know how you go on.

[TonyHSD]

Hi,

my advice is to find oem instructions how to do the job , print them on paper and follow strictly the manual. Do not rush and double check everything before going into next task. , you can also mark with a pencil each step is completed ✅ 

Here I can share a tip that I have been using in the past on timing belt changes on other cars with success. They might not be suitable for your engine but might be helpful to understand how things work. Good Luck and never rush to do it quickly.👍

 

When you set all sprockets at correct timing ready for dismantling do two marks on the tension side of the chain with white paint marker, one on the camshaft wheel and one on the crankshaft wheel, count the number of joints. Take both new and old chains , line up together and transfer the white markings onto the new chain. If there are any special tools to lock camshaft buy and use these so make sure camshaft is lock in place , Then when you start installing the chain start from top to bottom, align white markings that you had made on top and go towards bottom, if it’s too tense you can slightly move the crankshaft to accommodate aligning the white paint marks, once you do that you can go around the left side. Once you all set, yes spark plugs should be off the engine, rotate 3 times by hand to make sure all is set correctly and check again the oem timing marks if they are all aligned, the marks you had made with white paint are only for installing the chain and do not watch these anymore. 

[Hossam1516]

30 minutes ago, TonyHSD said:

Hi,

my advice is to find oem instructions how to do the job , print them on paper and follow strictly the manual. Do not rush and double check everything before going into next task. , you can also mark with a pencil each step is completed ✅ 

Here I can share a tip that I have been using in the past on timing belt changes on other cars with success. They might not be suitable for your engine but might be helpful to understand how things work. Good Luck and never rush to do it quickly.👍

 

When you set all sprockets at correct timing ready for dismantling do two marks on the tension side of the chain with white paint marker, one on the camshaft wheel and one on the crankshaft wheel, count the number of joints. Take both new and old chains , line up together and transfer the white markings onto the new chain. If there are any special tools to lock camshaft buy and use these so make sure camshaft is lock in place , Then when you start installing the chain start from top to bottom, align white markings that you had made on top and go towards bottom, if it’s too tense you can slightly move the crankshaft to accommodate aligning the white paint marks, once you do that you can go around the left side. Once you all set, yes spark plugs should be off the engine, rotate 3 times by hand to make sure all is set correctly and check again the oem timing marks if they are all aligned, the marks you had made with white paint are only for installing the chain and do not watch these anymore. 

 

6 hours ago, Catlover said:

Hi Hossam, it seems you have done your research well, read instructions and watched videos. You know the theory, now need to CAREFULLY put theory into practice. I suggest that is where others have gone wrong, they have not been careful enough. If you get the crankshaft and the camshaft teeth in the right position (get the manufacturers markers right place) then it should be ok. Just take your time, be careful, check your work carefully, you should be ok. Get it wrong, even by one tooth, then you will have problems. As Dean (furtula) says, take plugs out, revolve engine slowly by hand to check all is ok. It’s a long time since I done this job, principle is just the same, take your time, check and check again.            
Make sure you buy a quality chain, it does a lot of work, buy cheap and it may stretch more quickly.           
You will be buying a new filter and new engine oil, don’t buy the cheapest, buy quality filter and the correct grade of quality oil. Your car has done a lot of kilometres, treat it with respect and you will get many more hopefully.         
Change your engine filter/oil at least in line with Toyota recommendation, if not sooner. Look after the engine.                    
If the plugs and air filter have not been changed recently, maybe change then now. I know it’s all an expense, but it’s worth the effort to look after your car now, otherwise you will have a bigger expense sooner.            
Keep the form informed, let us know how you go on.

Thank you all for your help, of course i'll use an OEM parts; i'll get it from the dealership. my part list is: Chain tensioner , timing chain, slippers, water pump, set of spark plugs, air filter, valve cover gasket, RTV to make gasket on the timing chain cover, Toyota Engine oil 5W30 fully synthetic, oil filter and Toyota premixed coolant