Hyundai Repair: Timing Belt Marks..., california emmisions, valve cover gasket

Question
Should I let the same mechanic who changed the belt, water pump, and timing belt tensioner fix it?  It was only two months ago, and I have researched that changing a timing belt and these other parts for my type of car should be every 60,000 miles.
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OKAY, so what you are saying is that the dowel pins must be facing up and the marks on the edge of each sprocket are supposed to line up horizontally (adjacent)

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I had a mechanic take the cover off of my timing belt casing and he looked at the marks.  He said that the marks are supposed to line up with the holes for the screws to the case facing up towards the sky, is that true?  I have noticed on many models that the timing belt marks in my car should be facing each other inward.  I have a 1996 Hyundai Sonata and it wont start.  The engine is 2.0L with California Emmisions.
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If you look at the camshaft sprockets, you'll notice there are two pins behind each sprocket bolt.  Each of these pins should be facing upward.  On the edge of the each sprocket, there will be two marks.  These marks should be exactly adjacent to one another and should be at the same height as the top of the cylinder head.  I usually check the height by inserting a small screwdriver between the sprockets and verifying that it goes straight back to touch the valve cover gasket.
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That's exactly correct.

Answer
Presuming the camshafts are not properly timed, then I'd think you should at least first contact the place that did the work.  If they did the work improperly, it's their responsibility to fix it correctly, whether they do that themselves or they pay someone else to do it.

Here's the problem, though.  If the timing belt is not properly tensioned or installed, serious engine damage can occur.  And this is a somewhat tricky timing belt to install properly.  If this shop gets squirrely with not wanting to take care of something they've not done correctly, you should think hard about whether you wish to allow them to do work that could cause engine damage.