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I have just done my waterpump and timing belt (myself and my dad). But now i am noticing detonation in the high rpm region (6k>). We thought we put the timing belt in the exact same position as the old belt...but the old belt had stretched a bit. Would this detonation be caused by a misalignment of the timing belt with the cams? And how many teeth could it be out by? It runs well right up to about 6000rpm and then i hear the dreaded 'tink tink'. I am not driving it at the moment until i get it sorted out. I also adjusted the CAS but with little success. If i am a tooth out, does that mean the whole deal (harmonic balancer etc) has to come off again or is there an easier way?

I have not checked the timing with a timing light. I put a atmospheric bleeding BOV on at the same time but i don't think that has anything to do with the problem as that would only make mixtures richer.

Advice would be much appreciated.

Regards,

Scott

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You really need to put a timing light on it to find out what timing it is running before you / we can tell if it's a timing problem. All the way clockwise retards the spark, I think. Be aware that some timing lights seem to double the apparent timing angle.

Each tooth on the cam wheel is 7.5 cam degrees (15 crank degrees). There are 2 marks - one on the backing plate and one on the cam wheel for each cam. These should line up with each other when #1 is at TDC compression stroke.

Thanks blind_elk

Can someone give me a rundown on how to check the timing as i have the light.  Like where i get the pickup from etc.  And what marks i should be looking for.

Thanks,

Scott

I've never read anything specific about putting a timing light on an engine in these forums. Someone care to enlighten us?

thanks

-rb25

I've never read anything specific about putting a timing light on an engine in these forums. Someone care to enlighten us?

thanks

-rb25

Try here:

http://www.skylinesaustralia.com/forums/sh...g+light+ignitor

When it detonated, i backed off straight away...so i don't think i've hurt anything yet.

How many degrees does the engine advance under load? Does anyone know?

And which wire do i connect the pickup for the timing light?

I won't be taking it to a workshop now either. I've taken it apart once, so why not again. *sigh* I'll do the timing light tomorrow night.

Thanks for the help.

Scott

dude it sounds like you cas is not right , check the timing and adjust if it still pings after you do that covers out to check timing marks , you can do that with just the top cover off .

did you adjust the belt tensioner ? if you didnt that maybe your problem .

did you check all the 2 cam pullies marks to make sure they are lining up while the crank pully was at 12 o'clock mark ? ( it was obviously on the compression stroke otherwise it wouldnt run at all )

when you buy a new timing belt it has lines marked on it to make it easier for you to line it up every mark goes on the marks on the pullies .

And which wire do i connect the pickup for the timing light?

Scott: its not actually in that photo .. Its actual sits just behind the plastic cover from what I remember at the back of the engine. Its a white wire which basically just loops out. Its fairly obvious when you see it.

I found the loop, but it didn't work with my timing light. So coil pack out and stuck the pickup between the coil and plug. Bingo. Timing out... It's showing the marks way off to the left.

So here i go again and take it all apart. Well at least i'm learning.

Going by the correct procedure this time around (from the manual).

I'll let you guys know how it goes.

Thanks for all the advice.

Scott

you just have to turn the cas , if you do it while the timing light is pointing and the crank pulley you will see what way to turn it , if it doesn't go far enough it means the cas is one or more teeth out , take it off and put it right .

the timing light will not tell you if the valve timing is right so dong go taking everything off .

if it cant , take the cas out and put back in on tooth out to what it was before , if still not right turn it another tooth , its very easy mate .

with the timing light pointing on the crank pulley ( someone holding it for you ) turn the cas to the correct direction ( so it gets closer to the crank pulley mark ) if it doesn't come enough then its got to come out .

let me know how you go , dont take the covers off at this stage cause its got nothing to do with timing belt ( that doesn't mean the belt is right but it probably is )

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