45acpJr
1/2 ton status
Thanks for the advice diesel I'm having the shop replace the cams with edelbrock torkers, new bearings, oil pump, rings, and seal. He said rockers and rods look good. I guess I find out about the crank today
CK5
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Engine lost compression
- Thread starter 45acpJr
- Start date
45acpJr
1/2 ton status
Well the damage is worse than originally thought. Now we have flattened cams and piston number seven is cracked in several spots. And the cylinder wall has some damage. New plan is bore the cylinders .030 over, new flat top pistons, new cam and lifters. On the bright side the dipstick is still useable
CGT80
1/2 ton status
Just keep going...............pretty soon you will have an engine like my small block chevy. The oil pan, dip stick, and air cleaner housing are all factory parts, but I added a spacer to the air cleaner to sit high enough to clear the egr while using an eldelbrock 600 performer carb. Everything else is aftermarket and performance related other than the pulleys, brackets, air pump, egr, water neck, and AC. It pretty much started as just a set of headers since the old manifolds were cracked and the rest of the exhaust was bad as well. From there it has just been a matter of fixing what breaks and upgrading as I could up to now, 15 years after my dad gave me the truck. I have ridden around in it since 1984 (it is a 79). I'm hoping to get my rebuilt, and of course again upgraded, engine back in my pickup on Monday.
And, hopefully your machine shop will take care of the little details like running the proper bearings for the type of crank you have. Mine last build ran like a rapped ape for 27k miles and then took out the trans when the crank started to move enough. Of course it wiped out the cam, crank, bearings, and we found other iffy parts and machine work when it came apart. To make it worse, new parts are often not the best of quality. My crank was 450 bucks for a forged unit, and then it took another 320 bucks in machining and heat treatment to blueprint the crank so the stroke and clearances will be the same all the way throughout the engine.
A stock or very mild engine is less critical, but these things can still effect longevity. This engine is estimated to make 525 tq and over 400 hp out of 406 cubic inches. It is pretty much pushed to any reasonable limit for a small block (GM block) truck engine that will pass smog. I thought about stroking it as far as 434, but the prices just get insanely expensive and the factory blocks are not desirable for that extreme of an engine. Maybe I should have just swapped in some kind of a blown LS style engine that could be made smog legal but I am too far into this Gen I engine. Hopefully the third time is a charm.
Good luck on your build. These square bodies and old engine technology are kind of a sickness. In some ways a newer model truck might make more sense, but I just can't give up something this cool which gets more unique as time passes by. Actually I did buy a newer truck about 7 years ago...................An 88 K5 Blazer
And, hopefully your machine shop will take care of the little details like running the proper bearings for the type of crank you have. Mine last build ran like a rapped ape for 27k miles and then took out the trans when the crank started to move enough. Of course it wiped out the cam, crank, bearings, and we found other iffy parts and machine work when it came apart. To make it worse, new parts are often not the best of quality. My crank was 450 bucks for a forged unit, and then it took another 320 bucks in machining and heat treatment to blueprint the crank so the stroke and clearances will be the same all the way throughout the engine.
A stock or very mild engine is less critical, but these things can still effect longevity. This engine is estimated to make 525 tq and over 400 hp out of 406 cubic inches. It is pretty much pushed to any reasonable limit for a small block (GM block) truck engine that will pass smog. I thought about stroking it as far as 434, but the prices just get insanely expensive and the factory blocks are not desirable for that extreme of an engine. Maybe I should have just swapped in some kind of a blown LS style engine that could be made smog legal but I am too far into this Gen I engine. Hopefully the third time is a charm.
Good luck on your build. These square bodies and old engine technology are kind of a sickness. In some ways a newer model truck might make more sense, but I just can't give up something this cool which gets more unique as time passes by. Actually I did buy a newer truck about 7 years ago...................An 88 K5 Blazer
