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04-29-2009, 08:09 AM
I have a 1993 mazda 626 2.0 and i Had to change the timing belt, i have a diagram from mazda and when i set it i have no compression. can anybody please help. the marks that i used are 12 o clock on the bottom for the key and up top i have left camshaft the i is on the right and on the right the e is on the left aligning up the marks
01-24-2010, 01:13 AM
The engine is called an interferance engine which means if the timing belt breaks while driving/running the pinstons fly up at whateverRPM rate and smack the top of the piston into the bottom of the valves and end up bending them. Thus by benging the valves all your compression is escaping the combustion chamber. You need to rebuild the head or find another block.
Also if you changed an UNBROKEN belt because it was 'that time' due to age/mileage then when you timed the crank&cams you could have skipped a tooth when releasing the tensioner in which case again , with out PERFECT timing an interferance engine loses ALL compression. Just cranking the starter can cause the valves to bend. Either way you are most likely looking at a head rebuild.
A way to rule this out if you are in doubt is to get a cheap compression tested from any autoparts store and follow the basic compression test walk through you can find on GOOGLE and see for yourself.
Good luck and hope you ge it working again.
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