Cam and crank alignment, TDC problems
#1
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Cam and crank alignment, TDC problems
I have just had my head rebuilt, I was trying to install the cams but cannot seem to get them to line up properly. When I get the cams to align I cannot get the marks on the crank to line up to TDC. The head was milled just little bit, but I dont see how this could cause such a misalignment.
Here is how the cams and sprocket look:
The above pic looks normal, but they only line up when the crank is off.
Here is how the cranks looks when the cams are lined up:
Im really worried about interference. Any suggestions?
Here is how the cams and sprocket look:
The above pic looks normal, but they only line up when the crank is off.
Here is how the cranks looks when the cams are lined up:
Im really worried about interference. Any suggestions?
#2
You look to be one tooth off on the crank to timing gear chain. You should do the following. Remove the cams and timing chain tensioner. Remove the bolt holding the timing gear in place and slip the chain back a tooth.
With the gear held rotated to the left and the crank pulley at TDC, the two marks on the timing gear should be level with the top of the head. Once you are sure this is right, install the timing chain tensioner. Now install the cams
If you are off one tooth on a cam or timing chain the car will not start. The ECU is picky on the timing
With the gear held rotated to the left and the crank pulley at TDC, the two marks on the timing gear should be level with the top of the head. Once you are sure this is right, install the timing chain tensioner. Now install the cams
If you are off one tooth on a cam or timing chain the car will not start. The ECU is picky on the timing
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SkyladyZ (08-18-2019)
#3
Like Stratocaster said above, Ur one tooth off.. the two lines on the cam's should look like it would be one line if they were to be right up next to each other..
Get a new o-ring for the shaft idler gear bolt if you havent already, they leak oil when they get bad
Get a new o-ring for the shaft idler gear bolt if you havent already, they leak oil when they get bad
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Thanks all, you guys were correct.
I was getting confused because I thought that one chain link corresponded to one tooth on the gear. This assumption was incorrect, each chain link corresponds to two teeth on the gear. I just had to move the gear clockwise by one tooth while the crank and chain remained in place.
I was getting confused because I thought that one chain link corresponded to one tooth on the gear. This assumption was incorrect, each chain link corresponds to two teeth on the gear. I just had to move the gear clockwise by one tooth while the crank and chain remained in place.
#6
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dont worry about the marks on the big upper timing chain gear, it really doesnt matter where that thing is.. just make sure the marks on the cams are facing each other and the crank is lined up at tdc.
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S2kjay76 (08-11-2019)
#7
I have timing issues on my newly rebuilt F20C - when i connect the OBDII scanner it shows 25-27 (!) degrees at idle!
The engine has very rough idle. I've checked timing on my friend's s2k and it's only 5 degrees at idle. His car is bone stock.
My engine's block is milled 0.9mm and everything else is stock.
Here are the pictures when the crank pulley is at TDC:
We can't understand HOW timing could be 25 degrees at idle with cams and crank pulley positioned correctly!
Please kindly bare with me and help a.s.a.p.!
Also, please kindly explain the marks on timing chain gear - are they important?
What is their purpose?
Thank you all in advance!
The engine has very rough idle. I've checked timing on my friend's s2k and it's only 5 degrees at idle. His car is bone stock.
My engine's block is milled 0.9mm and everything else is stock.
Here are the pictures when the crank pulley is at TDC:
We can't understand HOW timing could be 25 degrees at idle with cams and crank pulley positioned correctly!
Please kindly bare with me and help a.s.a.p.!
Also, please kindly explain the marks on timing chain gear - are they important?
What is their purpose?
Thank you all in advance!
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#8
You can get the car to start? the exhaust looks to be off 2 teeth to the right, and the intake off by one to the left.
Your timing chain gear is off one link, but as wadzii said that is not an issue really, the cams are the issue.
Honda has two locations on the timing chain that are marked, one two link section for the oil pump and one one link section for the timing pulley. The Helms manual states where these links should be you the motor is put together to align thing properly. But since the tooth counts are different, the chains links walk as the motor runs so they are only aligned every X numbers of rotation. That is what wadzii is referring to. Where the marks on the timeing gear are is relative and not critical. It is the Cam gears alignment that is critical and their relationship to the crank TDC.
Your timing chain gear is off one link, but as wadzii said that is not an issue really, the cams are the issue.
Honda has two locations on the timing chain that are marked, one two link section for the oil pump and one one link section for the timing pulley. The Helms manual states where these links should be you the motor is put together to align thing properly. But since the tooth counts are different, the chains links walk as the motor runs so they are only aligned every X numbers of rotation. That is what wadzii is referring to. Where the marks on the timeing gear are is relative and not critical. It is the Cam gears alignment that is critical and their relationship to the crank TDC.
#9
We'll adjust them right away!
Yes, car starts ok but idle is rough.
And timing! OBD scanner shows 25 degrees!
#10
What are you using for an ECU? Surely not an OEM ECU. It is know to not start if you are off by one tooth.
Also you need to make sure the two cam marks are level to the cam tower mating surface. You picture looked to be shot from level that was right one for that.
Also you need to make sure the two cam marks are level to the cam tower mating surface. You picture looked to be shot from level that was right one for that.