need help with stuck crank

SR20fan · 03-30-2011, 12:47 AM

Hey guys. So, I was excited today to see my w10 motor go into my car. Well, at the last minute, a friend of mine asked if I ever tried to turn the motor by hand. And what you know, I never did try and it didn't turn. We then got it to turn, but its not doing a complete turn more like 3/4. So, there goes my day and had to put the motor back on the stand. I took off the lower and upper oil pans to get access to see the bottom end. I don't see anything wrong and the pistions are moving like they should. I even lubricated things that would seize up. Then I searched and found some things and saw things like the chain getting stuck somewhere, a stuck valve since the motor has been sitting for a long time for god knows how long, the tension might be bad.

Ive also read things like to spray wd-40 on the cylinder walls from the bottom end and also on top of the pistons due to rust. Can a small amount of rust on the cylinder walls really make it really really hard to crank the motor 1 full turn? Since I work 2 jobs and have only 1 complete day to work on my motor, I checked out the tensioner and there's nothing wrong. So, since its the end day, and I have to go back to work at my 2nd job tomorrow afternoon, I won't be able to pull off the front cover to see whats really going on until next monday. I decided to post this to get different opinions and help and someone to point me in the right direction. Thanks

cnick200sx · 04-08-2011, 05:43 PM

If it were me, I'de take the head off and check everything. Then I would change some stuff while the engine was apart like valves and valve seats and maybe the main bearings, rod bearings, piston rings and springs and retainers. My guess is that if its not the chain keeping it from turning, then it might be a bent valve. I would also change the chain tensioner cause those are plastic and dont tend to last long. Dont forget to time it right the first time when you put it all back together. after its timed right, rotate the engine 4 full times and the marks should be at the same spot you timed it at. somebody chime in if im wrong.