Timing Belt

[enomad]

Excuse my ignorance, my wife recently bought a '98 model Rav 4, (petrol engined) with 95000 miles on clock.

It's in very good condition all round with a lot of service stamps in the book, but I'm wondering if there's any way of checking if the timing belt has ever been changed?

ie By removing timing cover and checking condition of belt?

As I said excuse my ignorance in these matters!

[anchorman]

I'm afraid you would be taking a huge risk by trying to determin the condition of the belt by looking at it. If you have no evidence from the service history then you are well advised to change it as the engine is of the type that will be wrecked if the belt breaks;

Service interval 63k or 5 years

[koikeeper]

HI,

Mine is a 2002, 51 plate, NRG VVT-I 2.0l,

Am I right in thinking this has a chain & not a belt so does not need changing?????? is this inside the engine?

If it is a chain, what is the belt to the left of the engine (looking for the front), as you can probably gather I

know nothing about cars lol

john

[anchorman]

Yes you are right but on yours it is important to make sure the oil is changed frequently (at least per the service schedule) as poor oil will cause the chain to wear prematurely. A broken chain will do considerable damage to an otherwise very durable engine.

[enomad]

Thanks very much for that information.

I'll get it booked in somewhere for the belt.

[anchorman]

HI,

Mine is a 2002, 51 plate, NRG VVT-I 2.0l,

Am I right in thinking this has a chain & not a belt so does not need changing?????? is this inside the engine?

If it is a chain, what is the belt to the left of the engine (looking for the front), as you can probably gather I

know nothing about cars lol

john

Yes yours is a chain so same applies about looking after the oil.

The belt you can see down the drivers side is called the serpentine belt and drives all the auxiliaries like A/C, alternator etc. It needs to be changed periodically but you can see if its beginning to show signs of wear as it will develop lots of small cracks;

If it breaks in service it will be inconvenient but not wreck the engine.

[GT4 BOOSTER]

hi men , i just changed the timing belt on the wifes rav 4 1998 auto , is it possible to fine tune the timing , think it may be 1/2 a tooth out at the cam side. very faint tick/tap at idle when cold seems fine when hot , drives fine no noises at all when cruising at 70 mph. crank kept on moving when i tightened up the tensioner , right pain in the backside.

[anchorman]

You can only get it one full tooth out so if it seems a gnats don't worry. Tappets often rattle a bit when cold which probably explains it and you can also hear the injectors. You would know for sure if it was a tooth out because it would be either "flat" one way or or "back firing" the other.

Some diesels have a fine adjuster but not your 3FSE.

Congrats on doing it yourself.

[GT4 BOOSTER]

it didnt tap before , so should i just let it be or try for the perfect timing marks by stripping it down again .

gone are the days of turning the dizzy at times like this - sigh.

[anchorman]

Turning the dizzy would only adjust the ignition timing but the implications of being a tooth out are really more of a concern with regard to the valve timing.

I know what you mean about being half a tooth out as it sometimes looks like they don't quite line up but it is impossible to be half a tooth out, you can only be a full tooth out and if you whip the top cover off and look at the teeth then imagine being one full tooth out - you would have no doubt! That's one trough and one peak out so visualise a tooth either way of the marks!!!

If it really could be that far out it may account for some noise but I wouldn't expect it to be as sweet as you describe. So what about the noise? It either did it before and you didn't notice it or if the belt is too loose it can resonate (turn the engine backwards slightly to untension the belt on the longest run and it should be just slightly "springy" if you twist the belt by 90 degrees). Sometimes the belt catches the inside of the cover and rattles. You might be able to run it with some or all of the cover off to test.

[GT4 BOOSTER]

Turning the dizzy would only adjust the ignition timing but the implications of being a tooth out are really more of a concern with regard to the valve timing.

I know what you mean about being half a tooth out as it sometimes looks like they don't quite line up but it is impossible to be half a tooth out, you can only be a full tooth out and if you whip the top cover off and look at the teeth then imagine being one full tooth out - you would have no doubt! That's one trough and one peak out so visualise a tooth either way of the marks!!!

If it really could be that far out it may account for some noise but I wouldn't expect it to be as sweet as you describe. So what about the noise? It either did it before and you didn't notice it or if the belt is too loose it can resonate (turn the engine backwards slightly to untension the belt on the longest run and it should be just slightly "springy" if you twist the belt by 90 degrees). Sometimes the belt catches the inside of the cover and rattles. You might be able to run it with some or all of the cover off to test.

thanks for the advice mate- its definetly a tappet sound not belt slop , it goes off when i rev the engine when cold and its periodic , not there all the time,. im going to leave it and maybe the belt will stretch/soften a tiny bit over time and the timing may go ok itself. like i said though it runs as smooth as when driving.

wife drove home lastnight from work said she heard no noises and it drives as before - words i loved to hear , whoo hoo ..

[pinkbits69]

hi men , i just changed the timing belt on the wifes rav 4 1998 auto , is it possible to fine tune the timing , think it may be 1/2 a tooth out at the cam side. very faint tick/tap at idle when cold seems fine when hot , drives fine no noises at all when cruising at 70 mph. crank kept on moving when i tightened up the tensioner , right pain in the backside.

as it runs fine timing must be ok, it sounds like timing belt slap, this is due to the belt been too slack and slapping the cover. toyota brought out a shorter spring to get the tension right. you don't have to replace the spring but you have to manually tension the tensioner yourself if you don't. hope this helps

[GT4 BOOSTER]

after letting the tensioner loose i pulled up on the tensioner roller to take up any slack then tightened the nut , so i doubt its the belt slapping. The noise is more like an old vauxhall cam shaft type tap.

i may replace the tensioner spring , but it did look about the 46mm toyota recommend.

im beginning to think the belt maybe too tight now - although i could twist it still at its longest part,if this is the correct procedure ?

[anchorman]

That method is just a way of checking. The procedure calls for you to turn the engine and allow the tension spring to take up any slack. It is very important that the engine doesn't "rock back" prior to tightening the tensioner as that will un-tension the belt. A new belt will bed in and further tensioning should be taken up by the spring. It is acceptable to go through the process again now the belt has bedded but don't use any mechanical means to assist the tension spring.