This is how you quickly check if your valve (cam) timing is good or not. (* Only the valve timing. The belt tension and the balance shafts timing is a different story)
It would be useful if you know this method, for peace of mind, like when you want to confirm the valve timing after installing timing belt or when you are anxious about jumped timing belt etc.
I also gathered with some info about cam gears.
Hope this helps.
Step 1 : Align the crank timing marks as cam dowel pins on top
Set the cylinder #1 in the end of compression stroke which means you align the crank timing marks as the 6 bolt/7 bolt specific pic below as cam dowel pins on top at 12 o'clock, the same position as when you install the timing belt. It doesn't matter if the cam gear's horizontal timing marks (The red arrows in the cam gear pic #1) don't line up exactly straight. (Please refer to the tip #1 below)
If the engine has the timing cover and crank pulley, put a long screwdriver or so into the cylinder #1 spark plug hole and find the highest piston position. Or align the notch on crank pulley with the "T" mark on timing cover. But in some circumstance, this method doesn't guarantee that it aligns the crank timing marks.
6 Bolt
7 Bolt
Step 2 : Mark 12th peak tooth on both cam gears
Count 12 cam gear peak teeth by starting from the peak tooth right above horizontal timing mark on both cam gears, like the blue numbers in cam gear pic #1. Then, mark the 12th peak tooth on both cam gears.
- If 4g63, the 12th peak tooth will come at 12 o'clock and lined up with dowel pin.
- If 4g64, the 12th peak tooth will be off by approx half a tooth from the dowel pin position. The valley tooth right next advance side of the 12th peak tooth will be the one that comes at 12 o'clock and is almost lined up with dowel pin.
* Note : If speaking strictly, the exhaust dowel pin would be slightly off towards advance side from 12 o'clock. But here we call it as 12 o'clock to make it simpler.
Step 3 : Count the timing belt peak tooth numbers
Count the timing belt peak tooth numbers between the intake cam gear's 12th peak tooth and the exhaust cam gear's 12th peak tooth, like the green numbers in cam gear pic #1.
Make sure it's 15 teeth. The tooth count numbers must be "15", this means the cams are in phase.
For instance : If the timing is off by a tooth, it would be 14 or 16. If the timing is off by 2 teeth, it would be 13 or 17.
- In case if it's 14, either intake is one tooth retarding or exhaust is one tooth advancing.
- In case if it's 16, either intake is one tooth advancing or exhaust is one tooth retarding.
- In case if it's 13, intake is two teeth retarding or exhaust is two teeth advancing. Or intake is one tooth retarding and exhaust is one tooth advancing.
- In case if it's 17, intake is two teeth advancing or exhaust is two teeth retarding. Or intake is one tooth advancing and exhaust is one tooth retarding.
The valve (cam) timing is set correctly as long as if it's15 teeth when the crank timing marks are aligned.
Please keep in mind that the most important thing for setting the valve timing is, always it's with respect to the crank position. (Piston #1 and #4 position at TDC) If someone tells you that your crank is off, then that's incorrect and impossible, because the crank never be off, the valve/cam timing is.
Tips :
1 : Cam gear's timing marks don't line up straight
When you align the crank timing marks, sometimes the horizontal timing marks on cam gears don't exactly line up straight like the factory service manual shows, just slightly off. And it would make you worried even if you correctly installed the timing belt. That's just fine. That slight difference comes from resurfacing cylinder head/block, head gasket thickness difference, belt stretch, or/and worn cam gear/sprocket. To adjust this difference, you would need adjustable cam gears.
In case if the timing is off by mistake, the smallest unit would be one cam gear tooth. There is no half a tooth off. So if the timing is off, you won't be able to count 15 cam gear teeth between the 12th tooth of IN and EX cam gear.
Also vice versa, if you use a cam gear lock tool to make the horizontal timing marks on cam gears lined up when instal the timing belt, sometimes the crank timing mark would be slightly off for the same reason.
2 : If you need to show someone your timing
In case if you want to take a pic to ask for help to check your valve timing, align the crank timing marks as the cam dowel pins come on top at 12 o'clock (If you use a cam gear lock tool, remove it and align the crank timing marks), and don't change the crank position, and then take a pic straight at entire cam gears regardless of the position of horizontal timing marks on cam gears. No need to force the cam gear's timing marks to be lined up to take a pic. Because the cam gear's position when the crank timing marks are aligned is the position that we need to check.
3 : If you have the latest HKS purple 3 spoke cam gears (Refer to the cam gear pic #2)
This cam gear shares the dowel pin hole with EVO 4+, and also the baseline for degreeing is used as EVO 4+ timing mark. Which means the baseline/EVO 4+ timing mark would come on 13th tooth on intake and on 11th tooth on exhaust if the timing is set for the early 4g63. And that 13th tooth on IN and 11th tooth on EX is exactly in the midpoint of two spokes. This design often misleads people while setting the timing on the early 4g63. Because it would make it look like one tooth off (advancing) when you set the timing correctly like the cam gear pic #2.
Don't get tricked by the design, that's only an optical illusion. You are good as long as if it's 15 teeth as above.
4 : How to use EVO 4+ late 4g63 specific cam gears on DSM's early 4g63 (Refer to the cam gear pic #3)
I sometimes see some people buy a set of EVO 4+ specific cam gears by mistake or whatever reason have it on their DSM with their own way and often their timing is off.
You can use it on DSM but you have to re-mark the early 4g63's timing marks by yourself. The cam gear pic #3 is shown how you re-mark the DSM timing marks on EVO 4+ specific cam gears.
This is also like the tip #3, EVO 4+ timing mark would come on 13th tooth on intake and on 11th tooth on exhaust when the timing is set for the early 4g63 and it would make it look like one tooth off on each gear.
Don't get tricked by the design, you are good as long as if it's 15 teeth as above.
Cam Gear Pic #1
Cam Gear Pic #2
Cam Gear Pic #3
It would be useful if you know this method, for peace of mind, like when you want to confirm the valve timing after installing timing belt or when you are anxious about jumped timing belt etc.
I also gathered with some info about cam gears.
Hope this helps.
Step 1 : Align the crank timing marks as cam dowel pins on top
Set the cylinder #1 in the end of compression stroke which means you align the crank timing marks as the 6 bolt/7 bolt specific pic below as cam dowel pins on top at 12 o'clock, the same position as when you install the timing belt. It doesn't matter if the cam gear's horizontal timing marks (The red arrows in the cam gear pic #1) don't line up exactly straight. (Please refer to the tip #1 below)
If the engine has the timing cover and crank pulley, put a long screwdriver or so into the cylinder #1 spark plug hole and find the highest piston position. Or align the notch on crank pulley with the "T" mark on timing cover. But in some circumstance, this method doesn't guarantee that it aligns the crank timing marks.
6 Bolt
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7 Bolt
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Step 2 : Mark 12th peak tooth on both cam gears
Count 12 cam gear peak teeth by starting from the peak tooth right above horizontal timing mark on both cam gears, like the blue numbers in cam gear pic #1. Then, mark the 12th peak tooth on both cam gears.
- If 4g63, the 12th peak tooth will come at 12 o'clock and lined up with dowel pin.
- If 4g64, the 12th peak tooth will be off by approx half a tooth from the dowel pin position. The valley tooth right next advance side of the 12th peak tooth will be the one that comes at 12 o'clock and is almost lined up with dowel pin.
* Note : If speaking strictly, the exhaust dowel pin would be slightly off towards advance side from 12 o'clock. But here we call it as 12 o'clock to make it simpler.
Step 3 : Count the timing belt peak tooth numbers
Count the timing belt peak tooth numbers between the intake cam gear's 12th peak tooth and the exhaust cam gear's 12th peak tooth, like the green numbers in cam gear pic #1.
Make sure it's 15 teeth. The tooth count numbers must be "15", this means the cams are in phase.
For instance : If the timing is off by a tooth, it would be 14 or 16. If the timing is off by 2 teeth, it would be 13 or 17.
- In case if it's 14, either intake is one tooth retarding or exhaust is one tooth advancing.
- In case if it's 16, either intake is one tooth advancing or exhaust is one tooth retarding.
- In case if it's 13, intake is two teeth retarding or exhaust is two teeth advancing. Or intake is one tooth retarding and exhaust is one tooth advancing.
- In case if it's 17, intake is two teeth advancing or exhaust is two teeth retarding. Or intake is one tooth advancing and exhaust is one tooth retarding.
The valve (cam) timing is set correctly as long as if it's15 teeth when the crank timing marks are aligned.
Please keep in mind that the most important thing for setting the valve timing is, always it's with respect to the crank position. (Piston #1 and #4 position at TDC) If someone tells you that your crank is off, then that's incorrect and impossible, because the crank never be off, the valve/cam timing is.
Tips :
1 : Cam gear's timing marks don't line up straight
When you align the crank timing marks, sometimes the horizontal timing marks on cam gears don't exactly line up straight like the factory service manual shows, just slightly off. And it would make you worried even if you correctly installed the timing belt. That's just fine. That slight difference comes from resurfacing cylinder head/block, head gasket thickness difference, belt stretch, or/and worn cam gear/sprocket. To adjust this difference, you would need adjustable cam gears.
In case if the timing is off by mistake, the smallest unit would be one cam gear tooth. There is no half a tooth off. So if the timing is off, you won't be able to count 15 cam gear teeth between the 12th tooth of IN and EX cam gear.
Also vice versa, if you use a cam gear lock tool to make the horizontal timing marks on cam gears lined up when instal the timing belt, sometimes the crank timing mark would be slightly off for the same reason.
2 : If you need to show someone your timing
In case if you want to take a pic to ask for help to check your valve timing, align the crank timing marks as the cam dowel pins come on top at 12 o'clock (If you use a cam gear lock tool, remove it and align the crank timing marks), and don't change the crank position, and then take a pic straight at entire cam gears regardless of the position of horizontal timing marks on cam gears. No need to force the cam gear's timing marks to be lined up to take a pic. Because the cam gear's position when the crank timing marks are aligned is the position that we need to check.
3 : If you have the latest HKS purple 3 spoke cam gears (Refer to the cam gear pic #2)
This cam gear shares the dowel pin hole with EVO 4+, and also the baseline for degreeing is used as EVO 4+ timing mark. Which means the baseline/EVO 4+ timing mark would come on 13th tooth on intake and on 11th tooth on exhaust if the timing is set for the early 4g63. And that 13th tooth on IN and 11th tooth on EX is exactly in the midpoint of two spokes. This design often misleads people while setting the timing on the early 4g63. Because it would make it look like one tooth off (advancing) when you set the timing correctly like the cam gear pic #2.
Don't get tricked by the design, that's only an optical illusion. You are good as long as if it's 15 teeth as above.
4 : How to use EVO 4+ late 4g63 specific cam gears on DSM's early 4g63 (Refer to the cam gear pic #3)
I sometimes see some people buy a set of EVO 4+ specific cam gears by mistake or whatever reason have it on their DSM with their own way and often their timing is off.
You can use it on DSM but you have to re-mark the early 4g63's timing marks by yourself. The cam gear pic #3 is shown how you re-mark the DSM timing marks on EVO 4+ specific cam gears.
This is also like the tip #3, EVO 4+ timing mark would come on 13th tooth on intake and on 11th tooth on exhaust when the timing is set for the early 4g63 and it would make it look like one tooth off on each gear.
Don't get tricked by the design, you are good as long as if it's 15 teeth as above.
Cam Gear Pic #1
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Cam Gear Pic #2
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Cam Gear Pic #3
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