I found the answer here on the site, in the timing article by Bob O'Neill. I had it correctly the first time, by using the circular mark on the crank sprocket. Now, the question...why and how did it jump time? I installed a new tensioner and did not have the belt too loose, I am sure of that.
correct timing mark on crank sprocket? which one?
As a continuance of my two prior threads, I have determined that my valve timing was WAY off after I just changed my timing belt.
To verify...1990 2.5L. On the crank sprocket, there are two marks. One is on the outer circumference, and this mark is shaped like a letter A, or an arrow. A second mark, toward the inner portion of the sprocket, is a circle shape.
Which mark should be pointed at the corresponding mark on the intermediate sprocket?
The first time I changed the belt, I used the inner, circle shaped mark, because this put No. 1 cylinder at TDC. The A-shaped mark does not.
To verify...1990 2.5L. On the crank sprocket, there are two marks. One is on the outer circumference, and this mark is shaped like a letter A, or an arrow. A second mark, toward the inner portion of the sprocket, is a circle shape.
Which mark should be pointed at the corresponding mark on the intermediate sprocket?
The first time I changed the belt, I used the inner, circle shaped mark, because this put No. 1 cylinder at TDC. The A-shaped mark does not.
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1966 Crown Coupe, 2016 200 S AWD, 1962 Lark Daytona V8.
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Yes, use the circle mark on the crank sprocket for TDC. When the manual says that the cam sprocket oval should be facing up, that does not mean 'vertical up' but in line with the 'engine centerline up', which is canted slightly to the rear. The oval makes a good sight hole for the top nub of the valve cover seal on older 2.2L/2.5L engines.
I have found that the timing mark can move after a new belt installation due to the belt not being 'axially seated' on the sprockets. By turning the engine crankshaft over two full turns after belt installation and rechecking the marks, you may find that they are no longer lined up and may be a couple of teeth off. The service manual should state this as part of the procedure after the belt is installed.
I have found that the timing mark can move after a new belt installation due to the belt not being 'axially seated' on the sprockets. By turning the engine crankshaft over two full turns after belt installation and rechecking the marks, you may find that they are no longer lined up and may be a couple of teeth off. The service manual should state this as part of the procedure after the belt is installed.
Whenever I've done this job, I first align the timing marks with the belt off and then slightly offset them. That way, when I turn the tensioner with the belt on, the marks move back to where they need to be. If you put the belt on with the timing marks where they should be and then turn the tensioner, the whole setup may become slightly out of time. It will run, just have no power.
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You can see the circle dot on the crank line up with the notch on the intermediate pulley here.
I didn't find the marks move when I installed the belt and tensioned it. I set the tension so that the belt just turns 90 degrees when twisted on the longest span. Glad you found the trouble.
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I didn't find the marks move when I installed the belt and tensioned it. I set the tension so that the belt just turns 90 degrees when twisted on the longest span. Glad you found the trouble.
1966 Crown Coupe, 2016 200 S AWD, 1962 Lark Daytona V8.
Joined
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17,294 Posts
The intermediate shaft drives the distributor. The ign. timing should be rechecked after a timing belt service. A tooth off here can be compensated for by readjusting the distributor position.
Great, and thanks for the many responses. I hope to update with good news tonight...
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