98 LS400 Timing Belt Problem
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98 LS400 Timing Belt Problem
I am replacing the belt on my 98 LS400 and am having a difficult time getting the marks on the belt to line up with the camshaft pulleys.
So with the crankshaft timing mark at 6 and the camshaft pulleys lined up with the straight line housing marks I am unable to get the belt mark to line up. I can only get it to go to the tooth before the mark. It is the same on both sides. I have tried several times and without a belt stretcher I don't see any way of getting it on to where the marks will line up.
Also there are two markings on the camshaft housing one is a straight line and the other is T. The T has some paint on it that matches the paint on the camshaft pulley timing mark.
The manual indicates that the belt markings should line up with the camshaft pully and housing markings (straight line not the T) when the crankshaft timing mark is at 6 o'clock or TDC.
There are also instructions to advance the crankshaft 50 degrees and then line up the marks which does not make sense to me as it moves the camshaft pulleys forward as well. Are the T markings for the 50 degree advanced position of the crank?
I have made several attempts with either the crankshaft pulley forward a tooth to get the camshaft pulleys to line up but I am extremely concerned that the marks do not line up perfectly when I rotate the crankshaft through to verify the timing. I am beginning to wonder if the belt is not marked correctly. Any help would be appreciated.
So with the crankshaft timing mark at 6 and the camshaft pulleys lined up with the straight line housing marks I am unable to get the belt mark to line up. I can only get it to go to the tooth before the mark. It is the same on both sides. I have tried several times and without a belt stretcher I don't see any way of getting it on to where the marks will line up.
Also there are two markings on the camshaft housing one is a straight line and the other is T. The T has some paint on it that matches the paint on the camshaft pulley timing mark.
The manual indicates that the belt markings should line up with the camshaft pully and housing markings (straight line not the T) when the crankshaft timing mark is at 6 o'clock or TDC.
There are also instructions to advance the crankshaft 50 degrees and then line up the marks which does not make sense to me as it moves the camshaft pulleys forward as well. Are the T markings for the 50 degree advanced position of the crank?
I have made several attempts with either the crankshaft pulley forward a tooth to get the camshaft pulleys to line up but I am extremely concerned that the marks do not line up perfectly when I rotate the crankshaft through to verify the timing. I am beginning to wonder if the belt is not marked correctly. Any help would be appreciated.
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Are saying that as long as you have the timing marks lined up on the crank and camshaft pulleys the marks on the belt aren't necessary?
Regardless the timing marks should realign after two rotations on the crank correct?
Regardless the timing marks should realign after two rotations on the crank correct?
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Sorry to bud in for my first post but I am a Lexus technician. If you have a OEM belt...it should say left cam, right cam, and crank with indicating lines. As for the "I" and the "T" on the camshaft backing plates. "I" is the Top Dead Center position. "T" is marked where timing belt replacement is recomended as valve spring pressure is equal_i.e. when you have the belt off...there is less risk of the cam moving on its own.
If you don't have an OEM belt. Set everything to TDC...Cams at "I" and the crank at "0" degrees. Leave a pin in the tensioner when you put it on. There should be no slack between the cams or from the left cam to the crank pulley. The only slack should be on the tensioner side. Get everything on best you can but leave the pin in the tensioner as you tighten the two bolts. Then turn the crank over 2 revolutions and recheck your marks. If they are on...Pull the pin and finish up.
Hope this can help. Let me know if you have any more questions.
If you don't have an OEM belt. Set everything to TDC...Cams at "I" and the crank at "0" degrees. Leave a pin in the tensioner when you put it on. There should be no slack between the cams or from the left cam to the crank pulley. The only slack should be on the tensioner side. Get everything on best you can but leave the pin in the tensioner as you tighten the two bolts. Then turn the crank over 2 revolutions and recheck your marks. If they are on...Pull the pin and finish up.
Hope this can help. Let me know if you have any more questions.
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Thanks for input. Apparently the Duralast belt does not have the same marks as the OEM belts, and given the problems that I am having getting it to line up I think I will try another belt.
Perhaps you can tell me what is the best method for getting the crank to the 50 degree mark to match up with the camshafts at the T setting.
Perhaps you can tell me what is the best method for getting the crank to the 50 degree mark to match up with the camshafts at the T setting.
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#8
the marks on the belt will NOT realign after two full crankshaft rotations, from what I remember doing my timing belt.
the marks on the PULLEYS will realign after two full rotations.
from what i've read because the 95+ (yeah yeah, up for debate) are interference, you should set the pulleys in the correct TDC position before you remove the old belt. You should also (very important) arrest the pulleys before you try to install the new belt, as if any one of the three pulleys moves and is not directly in sync with the other two it could damage the valves.
the marks on the PULLEYS will realign after two full rotations.
from what i've read because the 95+ (yeah yeah, up for debate) are interference, you should set the pulleys in the correct TDC position before you remove the old belt. You should also (very important) arrest the pulleys before you try to install the new belt, as if any one of the three pulleys moves and is not directly in sync with the other two it could damage the valves.
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