Z24 timing chain, dizzy, oil pump and head.

[Hillbillybuddha]

Another question; I wish I had taken note of the position of the crankshaft sprocket and oil pump drive gear but I didn't... Each of these fears are concaved on one side. Do the flat or concaved side face the engine? I'm guessing flat towards flat surfaces but a more knowledgeable opinion would be great.

[Hillbillybuddha]

I ended up going the beveled side inward.

 

Is the oil slinger suppose to be loose between the two key ways?

[DMiller]

 Good morning!  

I just got a 1984 720 with a NAPS Z4.  The previous owner did the head within the last 1000 miles but did not do the timing chain.  Yesterday the engine developed a noise that turned out to be a broken timing chain guide.

 

Can I remove the timing chain cover on this engine without removing the head?

[datzenmike]

Yes, but it is bolted and tightly sandwiched between the oil pan and the front bottom of the head. Remove the front oil pan bolts up into the timing cover and well loosen the rest of the pan bolts down the sides half way. This will allow the pan to relax it's grip on the cover. The head has 4 X 10mm bolts down from the head into the top of the timing cover that have to come out. With the crank pulley, water pump, oil pump and distributor and the drive spindle between them removed, the timing cover can then be pulled out to the front. The timing cover sits ontwo small dowels so it will only move forward, there is little wiggle room.

 

Both the oil pan and the head have gaskets that may be damaged on removal. The head gasket only seals in fumes and small oil spray so a small amount of RTV will seal it just fine. The oil pan is much more important. If the gasket is ruined, buy another gasket and cut the front off of it. The block and the timing cover surfaces must be spotlessly clean, likewise the under side of the head and the top front of the oil pan. De-grease the surfaces with brake cleaner so any RTV used will stick and seal. As to RTV... I don't like it... but it does have it's uses. You do not need it on the block to timing cover surfaces if you have cleand them properly. Nissan didn't use it so trust your work. A small dab in the two joints between the oil pan and the cover and a small smear around the sealing surfaces on the top and bottom of the head gasket. Once everything is tightened, wipe off the excess that squashes out so the engine is not mistaken for a 305 chevy.