I put a new cam in my '87 Grand National. Also installing new timing gears and chain. Cam gear is a no brainer and can only go on one way. My question is for the crank gear. I know how to line up the dots on the gears. However, since there are 3 slots for the crank key on the crankshaft gear how do you position the crankshaft so you know you're using the correct key slot on the gear since each slot is 120 degrees variance? Do you set the crank where the #1 piston is TDC or what? Any help would be appreciated. Thanx
Timing gear marks when installing a new cam??
- Thread starter QuikRick
- Start date
TurboTdr3.8
Well-Known Member
- Joined
- Jan 15, 2013
The advance on the crank gear is 0 plus 4 and minus 4 , just line up the dot to dot that you want + or - or zero and you are good to go but I like the 7 key way sprocket so you can dial your cam in what the specs call for from your cam spec sheet .
- Joined
- Aug 1, 2003
yes have the #1 piston at TDC the crank key will be around 1:00 pointing to the center of the #1bore , line up the cam so bolts align and the gear dot is down , then you can set the gear set up with the chain so the dots are close and key at 1:00and , then slide it on and get the gear bolts installed rotate engine clockwise and recheck the dots with tension on the chain , dont install any puhrods until you're certain the cam dots are aligned, once your sure its right pull the cam gear bolts ,clean and loctite them , install and torque to 30 lb/ft
if you are going to degree it now you can install the degree wheel and get to it
if you are going to degree it now you can install the degree wheel and get to it
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Thank you - That is the answer to my question. Did that and I've got the 0 to 0 dots lined up. The on;y other thing is does it matter if #1 piston at TDC is on compression or exhaust stroke or will it work either way? Thanx
- Joined
- Aug 1, 2003
simple answer , it doesnt matter until the valvetrain is completed and you go to drop in and set the cam sensor
at that time you will mark the balancer and rotate engine and find 25ATDC on the compression stroke , align sensor dot on gear to left (pass fender) , drop the sensor in , set it and crank it down
http://vortexbuicks-etc.com/cam_sensor.htm
at that time you will mark the balancer and rotate engine and find 25ATDC on the compression stroke , align sensor dot on gear to left (pass fender) , drop the sensor in , set it and crank it down
http://vortexbuicks-etc.com/cam_sensor.htm
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Yes - did all that. Still can't get her to fire. Waiting for the local speed shop to call me and going to let them figure it out. I'm tired. LOL
- Joined
- Aug 1, 2003
FUEL- AIR- SPARK ...and compression
simple stuff first , check engine lamp on when key on , fuel pump primes
if no light is orange wire at battery connected
if no prime is fuse to fuelpump/inj blown
fuel pressure present (run power to prime wire until all the air is out of system)
check inj pulse with a noid light
if no activity on noid , check cam sensor signal voltage while cranking for a rise and drop , check cranks sensor signal for a rise and drop
if either sensor is not functioning you wont have fuel or spark
simple stuff first , check engine lamp on when key on , fuel pump primes
if no light is orange wire at battery connected
if no prime is fuse to fuelpump/inj blown
fuel pressure present (run power to prime wire until all the air is out of system)
check inj pulse with a noid light
if no activity on noid , check cam sensor signal voltage while cranking for a rise and drop , check cranks sensor signal for a rise and drop
if either sensor is not functioning you wont have fuel or spark
Yes sir. Believe me - I've done all that until I was blue in the face. Every once in awhile I'll get a slight backfire up in the intake but other than that - nothing. Just think it's time to let the pros have it. But thanks for all your input.
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