GSTwithPSI
Well-known member
Today I swapped in my HKS 272s. I used the RRE method and didn't remove the timing belt. Turned the motor to TDC, zip tied the belt to the cam gears and swapped out both cams according to the procedure. Everything went smooth.
After the swap, I rotated the motor over by hand a few dozen times. Everything lined up good, but it looked to me like the mark on the crank damper was a tiny bit off (like 1/16 of an inch). I attributed that to the shitty angle you have to look at the pulley from, and called it good. I waited 4 hours and went to start up the car...Nothing. It didn't even try and fire up.
At this point, I'm thinking I screwed something up. I pulled out my compression tester and I have zero compression on cylinders 1, 2 and 3. Cylinder 4 is reading 140 psi. The gauge blips quickly after each rotation on the cylinders without compression, but doesn't hold any pressure at all. Now, I'm really wondering what the hell is going on. How do I loose compression on 3 cylinders, and not the 4th? I start thinking maybe the belt jumped 1 tooth or something, and that's why the crank pulley looked a little off. I've had belts jump 3 teeth without bending valves though, so I'm thinking WTF? I decided I needed to pull the lower timing cover and see what's going on.
I pull the lower timing cover off expecting to find the timing jacked up. I rotate the motor over by hand again until all the timing marks line up. The timing is DEAD on. Everything is perfect. Now, I'm really thinking WTF is going on? The timing was fine the entire time.
I start thinking maybe the lifters need to be bled. Per the instructions from RRE, I waited 4 hours after I initially swapped the cams before starting the car, in order to let the lifters bleed down. I start thinking maybe they didn't bleed down, and the valves are hanging. I pull all the lifters out, and bleed each one. I throw them back in the car and do another compression test. Still, Zero on 1, 2 and 3...140 psi on 4.
I'm at a loss. The car was running fine before I decided to go f***ing with it. I can say for absolute certain the car was never turned over out of time. I'm tempted to throw the stock cams back in just to see what happens. The sh*t I'm experiencing just defies logic. I don't know how compression shits out on 3 cylinders unless the valves are bent. Furthermore, I don't know how you bend valves when the car was always in time. The only thing I can think, is the lifters were still pumped up and maybe caused 3 of the 4 pistons to smack the valves. Can that even happen? Maybe I'm missing something here? You guys have any ideas?
After the swap, I rotated the motor over by hand a few dozen times. Everything lined up good, but it looked to me like the mark on the crank damper was a tiny bit off (like 1/16 of an inch). I attributed that to the shitty angle you have to look at the pulley from, and called it good. I waited 4 hours and went to start up the car...Nothing. It didn't even try and fire up.
At this point, I'm thinking I screwed something up. I pulled out my compression tester and I have zero compression on cylinders 1, 2 and 3. Cylinder 4 is reading 140 psi. The gauge blips quickly after each rotation on the cylinders without compression, but doesn't hold any pressure at all. Now, I'm really wondering what the hell is going on. How do I loose compression on 3 cylinders, and not the 4th? I start thinking maybe the belt jumped 1 tooth or something, and that's why the crank pulley looked a little off. I've had belts jump 3 teeth without bending valves though, so I'm thinking WTF? I decided I needed to pull the lower timing cover and see what's going on.
I pull the lower timing cover off expecting to find the timing jacked up. I rotate the motor over by hand again until all the timing marks line up. The timing is DEAD on. Everything is perfect. Now, I'm really thinking WTF is going on? The timing was fine the entire time.
I start thinking maybe the lifters need to be bled. Per the instructions from RRE, I waited 4 hours after I initially swapped the cams before starting the car, in order to let the lifters bleed down. I start thinking maybe they didn't bleed down, and the valves are hanging. I pull all the lifters out, and bleed each one. I throw them back in the car and do another compression test. Still, Zero on 1, 2 and 3...140 psi on 4.
I'm at a loss. The car was running fine before I decided to go f***ing with it. I can say for absolute certain the car was never turned over out of time. I'm tempted to throw the stock cams back in just to see what happens. The sh*t I'm experiencing just defies logic. I don't know how compression shits out on 3 cylinders unless the valves are bent. Furthermore, I don't know how you bend valves when the car was always in time. The only thing I can think, is the lifters were still pumped up and maybe caused 3 of the 4 pistons to smack the valves. Can that even happen? Maybe I'm missing something here? You guys have any ideas?
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