Engine timing

MAZDA
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GIBOOKS
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Hello. I have a Mazda Allegro 1998 with a 1.8L engine, automatic 106.000 miles . I decided to take off the cylinder and have it serviced. I serviced the fuel injectors and changed filters. Before the extraction of the cylinder head the compression at each cyclinder was 160 - 170.

Once assebled the cylinder head again, the engine know hesitates at idle and turns off, cant sustain the a/c and the compression has gone down to 120. Can the sole cleaning of the carbon deposits in the pistons and the cylinder head cause such a drop in compression? Could this be bad timing of the engine? Once the cylinder No. 1 is at TDB how should the intake and exhaust cams be pointing?
Thank you.
Sep 14, 2007 at 3:25 PM
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RASMATAZ
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[quote:989d28933c="gibooks"]Hello. I have a Mazda Allegro 1998 with a 1.8L engine, automatic 106.000 miles . I decided to take off the cylinder and have it serviced. I serviced the fuel injectors and changed filters. Before the extraction of the cylinder head the compression at each cyclinder was 160 - 170.

Once assebled the cylinder head again, the engine know hesitates at idle and turns off, cant sustain the a/c and the compression has gone down to 120. Can the sole cleaning of the carbon deposits in the pistons and the cylinder head cause such a drop in compression? Could this be bad timing of the engine? Once the cylinder No. 1 is at TDB how should the intake and exhaust cams be pointing?
Thank you.[/quote:989d28933c]

Welcome to 2carpros

Double check whether you are in deed at TDC on compression stroke on no.1 cylinder. To verify remove distributor cap is the rotor pointing to no.1 cap tower if not. you have to verify the valve and ignition timing. My guess its probably on the exhaust stroke on no.1 cylinder
Sep 14, 2007 at 4:06 PM
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