1997 EX f22b1 - Picked up this 5 mt off craigslist for 600 about two weeks ago. Ran perfect with 285000 miles. I spent a few days changing fluids, new battery, new power steering pump etc. Guy owned it said it would need timing belt. I did a Dodge Stratus 2.4 last year and it was good to break my cherry with. I ran a compression test and when I did I found out the hard way that at least cylinder 2 and 3 were helicoiled or repaired in some way. Cylinder 2 helicoiled comes out intact threaded on plug. Cylinder 3 did not and fell into head. Decided to pull head and get it repaired correctly and do timing belt and other leak repair while I'm in there. Sorry long winded, wanted to give background. I just set at tdc and proceeded to take off crankshaft bolt and pulley. That went well. Now I would like to reset at tdc but I cannot rotate engine counter clockwise, it just stops with my camshaft up sign at about ten o'clock position. It will rotate clockwise although I didn't move it but about an inch clockwise out of fear that reverse rotation would not be good. Does anybody know what I've done or can do to do a full rotation back to tdc? Thank you in advance.

 

Engine is interference. If the crank stopped then a piston probably contacted an open valve.
Rotate the crank slowly the opposite direct to get it back to TDC.

 

Thank you for the info. That does make sense, although rotating it backwards did put both cam and crank at tdc. Wouldn't I have had to have a break in timing for them to make contact? Timing belt is intact. I did have it in first gear while breaking loose the crank bolt. Would I have broken something by having it in gear. I also had my driver motor mount off when I removed crank bolt. I guess if I'm removing the head this is all moot anyway. I can see or repair any damage when it's removed.

 

Worse case scenario, you can loosen up cam cap bolts. Lift off, but don't remove(Allowing all valves to go closed...then you can set everything to TDC, both cam and crank. Then re-torques cam caps.

 

Only time you don't want to rotate the engine backwards is when setting the timing belt tension. There is no voodoo or magic once the tension has been set. If there is slop on the 'slack' side then the tension has not been taken out of the belt properly. Even if the tension is correct between the crank and cam side, if the water pump/tensioner side is sloppy when the engine is running that slop would allow the cam to overrun and vary the cam/distributor timing to the crank.

Line up Cam to UP and crank to TDC.
Install belt.
Rotate crank 3 teeth(to remove slack)
Lock down tensioneer nut.
Rotate crank 360° and 720°
Verify timing is still spot on.
Done.
You will be able to rotate the crank forwards or backwards without worry of going 'out of time', although I would not make a habit of rotating the crank 'backwards'. But this has more to do with older belts and pulling on them the wrong way. Kind of like old bias/ply tires, you don't want to 'unravel' the cords after they have been 'pulled' in one direction.

When putting the head on, rotate the crank 90° from TDC, doesn't really matter which way, this brings all the pistons half way down the cylinders leaving you plenty of clearance no matter which way the cam is rotated on the head. Then rotate the cam to 'UP' and slowly bring the crank back to TDC to install the timing belt.

Cam is always half speed of crank, it will never vary.

 

Thank you thank m73 and MAD MIKE! I appreciate all the valuable info. It did rattle me when I thought about Pistons to valve contact when everything ran and was and still looks n time. I will be heavily involved in this for the next week or two. Again, thanks