1984 318 crankshaft swap into pre 74 318 block

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swing69

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My 84 318 block is cracked. I want to swap the entire 84 rotating assembly into the earlier block.

I understand the #3 bearing changed at the thrust bearing area, but I'm not clear as to how.

Can I make this crank swap? will the crank work? what do I need to do?

I also want to use the earlier 273 balancer, as this is going into a 1965 vehicle with right side timing marks.

thanks.......
 
I wasn't aware that they changed the bearings on the small blocks, the big blocks changed to a larger thrust bearing surface I think in 74 or so. With the big blocks you can swap around cranks, just get the right bearings for your block. The later bearings will not work in the earlier blocks, but the earlier bearings will do ok in a later block. Just buy bearings that fit your block and you should be ok.
 
Can you re-use that bearing from the older worn out engine in the newer engine. As in, the bearing isn’t work out? It’ll fit the crank.... if your not cutting the crank, just a direct swap...
 
I think only the 360 changed thrust bearings but I might be wrong.
 
It is my understanding that the different thrust bearing/year of block issue is only the 360. I have not ever heard of any issues with 273/318/340 crank/blocks/thrust bearings. Myself, went from a 71 to an 84 block, no problems
Just bolt it together
 
Seems like I looked this up once upon a time, and the thrust bearing change is for the 318's. The width of the thrust bearing flange got wider at some year...'74 ish? I have a 273 block where wider flange late bearing fits up just fine, but the safe route is to use the earlier thrust bearing in an early block.

As for the damper, it if it an original 273, then the mark on the damper will be for marks over on the right side. (You can tell: the keyway in the damper hub should not be too far CCW from the timing mark when viewed from the front. ) But the water pump will have to be an early, iron one to be able to see the marks, AND the later radiator hose connections will be on the wrong sides for the early pump. So you either work that out... or use a later damper, pump, and timing cover with the mark on the left. Of course, you can always put a timing tape on the damper and a timing tab anywhere you please.

FWIW... if that 273 damper is the original then it rubber is shot. It won't damp well and if the rubber is cracked, there is a chance that the inertia ring can some loose and fly off. So be careful; a new one may be in order IMHO.
 
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