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77 powertrain swap

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BradP1987

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So my 77 that I bought broke down on me the other day. It just died while I was driving and now it wont even crank. Not sure what is going on...gonna start tearing it down tomorrow. My idea right now though is to swap the fresh 350 and 465/205 from the 72 I was going to restore into my 77. Can anyone tell me what all might have to be altered to make this setup work in my 77? I know I will have to cut the floor for the tranny and the transfer...but what all else will I have to alter or buy?
 
I believe the shifter is different, and I am sure the pedals and linkages are different as well. Look for a junkyard or scrap 1985-1987 pickup, Suburban, or Blazer/Jimmy with an SM465/NP208. Take the complete setup from that. Then you end up with the superior hydraulic clutch setup and all of the parts to make it work.

Martin
 
There is a post in the technical articles on this swap! All the info you need is there. You can go mechanical linkage or hydraulic for clutch operation. My preferance would be mechanical with upgraded heim joint linkages. It's also my opinion that the 4spd makes it like driving a dump truck. Its not like banging gears in a car.
 
earnett said:
There is a post in the technical articles on this swap!
Click to expand...

Yeah for some reason it wont let me view that forum.

I understand that it isnt like bangin gears. I drove my 72 for a while with the 4 speed and feel like it is a better choice for off road
 
Update

Well...while pressure washing the engine this evening after work, got my handy flashlight to check it and make sure it was pretty clean. And what did I find? I found the outermost portion of the harmonic balancer had separated and fell off even though the timing chain cover shoulf have stopped it. Not sure of the damage, but really hoping it didn't break the crank or screw up anything else. Gonna try to take everything off tomorrow and check the oil pan and filter to see if it ruined the bearings.

Anyone ever had this happen to them? If so, what all did you end up having to replace? Should I go ahead and rebuild the whole block?
 
I wouldn't say its un-fixable until you try putting a used balancer back on it and run it--I have seen several older small blocks fling the balancer apart or have it come completely off and the engine ran fine once another one was found and installed....older small blocks didn't have a bolt to hold the balancer on and it wasn't that uncommon to have one fly apart or come off..........................................................................................................most memorable one I saw fail was on a 67 Corvette with a 327years ago--,guy did a high rpm burnout leaving the bar one night,and when he got about 200 feet up the street with the engine taching 6 grand,the balancer walked off the crank snout and flew off!--it trashed the radiator and some of the hood,but he was able to get another balancer and it ran OK once it was reinstalled...
 
Well finally got around to taking everything off of the front end of the engine. Everything so far looks pretty good. Water pump was a little rusted, so I'm going to go ahead and replace it, and the HB, which wasn't broken, but pretty worn out. The timing chain and gears look fantastic though, the gears are not even the slightest bit worn down yet, and the chain is perfect as well. Drained the oil, no sparkles, but its parked on a bit of a decline right now, so I'm going to take the pan off tomorrow and inspect it and the bottom end a little further.

I am still stuck though, it still will not turn at all. :what: My dad, who has helped build 2 of my engines in previous trucks, said that he has seen a couple of old 350's get rebuilt, and the owners used the old factory pushrods, and a couple bent and broke, and that locked up the engine. Anyone else heard of this happening? If so, what are the possible damages done to my block?

Thanks for the help guys
 
I pulled this out of a 350 recently:

8052315220_4c0e432359_b.jpg


Now, it ran absolutely horrible this way, but it did run and it certainly wasn't locked up.
 
uh oh

Not sure what got ate all to hell, but it doesn't look good. Looks like I'm gonna be pulling the block and rebuilding it now. No clue what it is, anyone got any insight?

Thanks

20130113_110942.jpg


20130113_110937.jpg
 
Ha, I found a jewelers magnifying glass, and that's deff bearing material plus whatever ground up, be it rod and crank or crank and block.

The balancer being all messed up, before it completely tossed it, will cause the crank to wobble and tear up the mains. Hopefully thats not the case, as that brings the suck bad. Hopefully you got away with a spun rod. Which isnt near as bad.


Wish I had taken pics of it, but we had a 69 El Camino SS that was a friend of mines and worked on it in HS, and it ran all sorts of stupid sometimes, and ran sorta decent other times. We checked and rechecked everything. Finally, we ended up pulling the motor to rebuild it for more HP of course... (you know how you was in HS) and it had snapped the crank in half, between the center 2 main bearings. And somehow it would fire up and spin both sides of the crank just right and it would run sorta ok, and other times not so much. No glitter or bearing material in the pan at all, and all the bearings were fine, plus it never overheated, and always kept the battery charged. Sometimes engines can act all sorts of ridiculous, like an X wife.
 
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