Which 4cyl? There was a 1.8 & a 2.0 for that year (same engine family though so not too much of a difference I think). On my 323 its only 8 bolts I think and the timing cover on it doesnt have to seal any oil so I just reused that one. Should have no problems though, valve covers are usually simple, while its open take a look at how clean or sludgy it is inside, if clean have them keep doing what their doing, if sludgy they need to change oil more often. Also be sure to clean both surfaces well before you reinstall the cover or it may leak again in the near future and dont over tighten the bolts
1997 Mazda 323 1.3L 5-speed (130,000km)
2006 Mazda3 1.6L 5-speed (40,150km)
1989 Ford F250 7.3L IDI non-wastegated turbo 5-speed
239,000 miles and counting, ORIGINAL CLUTCH, still going strong. (In USA, dont have it here in AT)
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