Timing belt/ cam sprocket help needed
#1
10th Gear
Thread Starter
Timing belt/ cam sprocket help needed
I set tdc to everything and got everything taken apart, but when I was putting everything back together, I noticed that the rear cam sprocket had turned clockwise about 10 degrees. I tried to turn it back by hand and it would just barely move, so I took off valve cover and loosened cam "cage" and turned the cam sprocket back to tdc, but then when I tightened everything back up on cam, it popped back to the position it was at before 10 degrees off. I just put the new timing belt on with the harmonic balancer and tried to turn it slow to see if there was any valves hitting the piston, but after about a 1/4 turn it ran into some pressure and just started loosening the crank pulley bolt. I'm not sure if that was valves kissing pistons or just because I didn't torque the bolt enough because I knew I was going to be taking it off again. Any help would be appreciated. I'm not sure if there is a way to keep the cam at tdc while tightening up the cam cage, if I should just make a tool that I can put pressure on to turn the cam while cage is tight, or if I'm just totally screwed. Its my DD so I am trying to get it back together asap. Thanks in advance
#2
10th Gear
Thread Starter
#3
Race Director
Rear sprocket can and probably will move off of TDC either direction by a small amount. Just put a socket on the sprocket bolt and turn it back to TDC. It should only need to be turned ~ 1/8 of a turn. Then put the belt back on. There is a "sweet spot" when trying to land the rear sprocket at TDC. Just play with it until you get it there, and then put the belt back on.
When you turn the crank bolt with the belt on, you will get resistance from the valve springs and compression as you turn. That's normal, but you should be able to pull through it. There is an epic TB thread in the main 3G forum. Do a search for it.
When you turn the crank bolt with the belt on, you will get resistance from the valve springs and compression as you turn. That's normal, but you should be able to pull through it. There is an epic TB thread in the main 3G forum. Do a search for it.
#4
10th Gear
Thread Starter
Yea, I was going off that thread to do the TB change, they did a great write up on it. But I just didn't know if force turning the cam would damage anything. Thanks. I'll just turn it and get it put back together.