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I was assembling a 3K on the bench at the weekend, & thought I take a few pictures of the fitment aligning marks for the timing chain, that might help those new to K Series engines, or that don't have a factory workshop manual. Getting this wrong, can cause great heartache, especially if you've assembled the engine & refitted it to the car, only to find, you've got it wrong. A dizzy fitted incorrectly, is easy to rectify, but a timing chain "refit", can be very frustrating. The camshaft & crankshaft must be in a precise postion, when the sprockets & chain are fitted. Toyota have provided some markings, which must line up. The crankshaft sprocket must be in the postion with no:1 & no:4 pistons being at TDC (top dead centre). The keyway for crankshaft sprocket should be at 12:00 o'clock. ie: vertical, with the engine horizontal. There is a small mark at about 5:00 o'clock, which I have marked with "whiteout" for these photos to make it a bit clearer. You can just see the "dot" in the pic above. The camshaft has two sets of markings. The location pin on the end of the camshaft that engages with the camshaft sprocket, must line up with the camshaft thrust plate alignment marker. Ensure the camshaft thrust plate is not fitted upside down, if you haven't already fitted the timing chain cover "back plate". The thrust plate is not synmetrical, as is shown in the pic above. These two markings are obscured, once the camshaft sprocket is fitted. The camshaft sprocket has a small mark at about 11 o'clock. The timing chain can usually be fitted with the crankshaft sprocket already fitted to the crankshaft, as long as the chain anti-vibration plate has not been fitted. The factory manual depicts two links on the chain 180 deg apart which are a different "colour", to aid in getting the next step right. Lay the chain out stretched with the chain in a straight line & mark two links, one at each end (white out). Fit the chain over the crankshaft sprocket, with one marked chain link lining up with the dot on the crankshaft sprocket at 5:00 o'clock. Fit the camshaft sprocket to the spretched chain so that the dot at 11:00 o'clock lines up with the other marked link. Taking care not to dislodge the camshaft position, the camshaft sprocket can then be located on the end of the camshaft, with the locating pin. Everything being OK, you should be able to hold a ruler or straight edge across the centre points of the camshaft & crankshaft, and the two markings on both sprockets should line up, as per the photo below. Slip the timing chain cover on, just using the location pins. With crankshaft key fitted, slip on the crankshaft pully. The TDC timing mark on the pulley should line up with 0 deg on the cover timing marks. The only proviso with this technique, is that if fitting a brand new chain, you may have to fit chain & both sprockets at the same time, as there may not be enough sideways flexibility in the chain. Cheers Banjo
