for reference, this is generally also applicable to a Mazda 3, but obviously there will be differing steps in places.
did the head gasket job over the weekend. overall not terribly difficult, but definitely not the most fun. in order to remove the head, basically the entire top end needs to be disassembled. best way to approach this is:
1. drain the block and radiator, remove both the upper and lower radiator hoses.
2. remove the air intake boot and air intake. in order to do this, remove the drive belt and remove the power steering pump. just set it aside, not need to disconnect it from the rack.
3. disconnect all connectors and unplug the PCM connector, then set wiring harness aside
4. remove A/C compressor (same as power steering pump, don't disconnect, just set aside), alternator, and the accessory mounting bracket.
5. remove the valve cover.
before you do anything else:
there is a very specific sequence to follow for this engine because the crankshaft timing chain sprocket is not keyed, which is literally mind blowing. one of the most asinine engine designs of all time. you need to either purchase or rent a Ford/Mazda timing tool set from AutoZone. first, set the engine to TDC at cylinder 1. there is a small 10mm bolt at the bottom left hand side of the engine, near the CKP sensor; remove that and fully insert a timing peg, then turn the engine clockwise until the crankshaft counterweight hits it. the engine is now at TDC. i recommend to use the thickest peg in the set (there are 3). you can be certain it's a TDC by: putting a long screwdriver in the spark plug hold in cylinder 1 and rotating the engine, and by checking that the notches on the back of the camshafts are aligned. the lobes on the camshafts will also be pointing down and outwards at cylinder 1.
6. now that the engine is a TDC, remove the crankshaft pulley. the last photo is the tool i used to hold the pulley in place to prevent the engine from rotating. you can purchase one from eBay for $25. the inserts that come with the tool are too big to insert into the pulley holes, so you will need to purchase some bolts that will fit. NB: i recommended using the thickest timing peg above in case the sprocket holder slips and the timing pegs momentarily stops the engine from rotating.
7. remove the CKP sensor, then the front engine cover.
8. take a picture of the position of the camshafts for reference.
9. remove the timing chain tensioner and the timing chain.
10. remove the camshafts.
11. remove the exhaust manifold. in order to do this you will need to remove upper O2 sensor.
11. remove the head. make sure to loosen the head bolts in sequence from the middle ones outwards. there are 10. do them in pairs. you will need a T55 or T60 bit.
follow these steps in reverse to reassemble.
Images (Click to enlarge)
Jul 6, 2021 at 7:59 AM
