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Old 07-05-2010, 06:13 AM
tennsmith tennsmith is offline
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Join Date: Jul 2010
Posts: 3
Default Re: 1999 2.5 ranger timing belt issues please help!!!!!!

Ben, a couple of issues. Because the cam turns at 1/2 the speed of the crankshaft, it is possible to have the crank keyway at 12'Oclock and not have the cam/oilpump marks aligned visually. If it appears "off", rotate the crankshaft one more revolution and see if they now align. If you are aligning it for the first time, this 1/2 speed thing isn't important, but after the belt is on and tensioned, it will have a crank revolution where things are lined up and one where they are not. The cam has a diamond and a triangle on the metal ring behind the pulley. The diamond is supposed to be "about" 12 O'clock, but the mark you need to pay attention to is the triangle which should be opposite the triangle on the back of the timing belt housing. At the same time, there are a couple of diamonds to match on the oil pump pulley, one on the ring behind the pulley and another on the back of the timing belt housing. Not sure why it is critical for these marks to be lined up (oil pump) but maybe it is just to ensure the belt is properly positioned.

Now a second issue, if the belt broke while the engine was running....there may be engine damage as well...it all depends on whether this is an "interference" or "non-interference" engine and by that I mean whether the valves (if open) will strike the piston at TDC or not. When the belt broke, the cam stopped turning and one or more valves would be open at that time. Question is, did they strike the piston or not? Someone more familiar with this engine than I may be able to answer this question.

If a valve hit a piston, you have either a bent valve which now will not close, or a piston with a hole in the top...or maybe both.
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Bob Smith/Huntsville, AL

Last edited by tennsmith; 07-05-2010 at 06:17 AM. Reason: clarification/editorial
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