I have a 1999 mazda protege 1.6L,
I am trying to get the car to start after replacing the Crankshaft seal.
In the process I had to remove the timing belt. I aligned the Crankshaft and camshafts at TDC, rotated engine twice and everything aligned but but the car still will not start. I turned the camshafts with a socket and ratchet several times to align them at TDC. I was then told by a mechanic that I was not suppose to touch the camshafts and that I now ran the risk of damaging engine and bending valves especially after trying to start the engine several times. But I also was told by another mechanic that the car has a non interference engine and that this should not happen. Either way the car does not start, I was told by one mechanic that most likely I will have to get my cylinder head replaced while the other mechanic suggest it maybe something else like a crankshaft sensor malfunction or something etc. Please Help!
You never rotate the cam shafts when the timing belt is removed.
It can bend valves.
Tester
Does this sound like the most likely scenario even though its a non interference engine ?
It’s a non interference engine.
So no.
Tester
Take your timing belt off, don’t move the cams but rotate the crankshaft one turn and put the belt back on. You have the spark plug firing at the top of the exhaust stroke, not the compression stroke. The crankshaft rotates twice for every camshaft rotation.
Hi oldtimer:
Maybe I’m missing something, but can you explain this more in case I am?
With the belt off, if the crankshaft is rotated one full turn, when done, won’t the pistons be back to where they just were?
Danny:
I didn’t see you mention that you verified the crank and camshaft timing marks were properly aligned after you put the belt on. How did you verify that?
Also, did you correctly reinstall the crankshaft sensor?
Turning the crankshaft back 90* on a 4 cylinder engine will put all pistons mid way in their cylinders and allow turning the camshafts on interference engines. Once the cams are on their marks the crankshaft can be turned clockwise into position and the belt installed.
If you remove the valve cover you’ll be able to determine if the correct valves are open and closed with the harmonic balancer timing mark at TDC with cylinder 1 on its compression stroke. Might as well adjust the valves then, too.
It is a 4 cycle engine, intake (piston moving down), compression (piston up, power (piston down, exhaust (piston up. This requires two turns of the crankshaft.
While the crankshaft is turning twice the camshaft is turning once, and on cars with distributors, they only turn once. Each piston comes up to top dead center twice in the cycle. once to begin the power stroke and once to begin the intake stroke.
If you rotate the camshafts when you have the belts off you run the danger of having the cam and crank out of phase. If you had a distributor engine you could crutch it by just moving each spark plug wire half way around the distributor cap.
Having said all that, the timing marks on the cam should line up 180 degrees off if you are on the wrong stroke. Apparently my brain doesn’t work as well after midnight.
Usually the way this sort of thing would be done, before removing the belt you’d align the marks. then you wouldn’t touch either pulley until you put the belt back on. At this point are the timing marks on the crankshaft pulley and the camshaft pulley correctly aligned, per the factory service manual diagram?
Additionally, and maybe the key to your problem, is that the camshaft pulley AND the crankshaft pulley must both be at TDC WHILE CYL. #1 is on its compression stroke. The distributor or the crankshaft position sensor will be signaling the plug in cylinder 1 to fire a few degrees before that TDC alignment on the compression stroke.