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Discussion Starter · #1 ·
I only have 4 of 8 pistons installed and it's taking 35lbs to turn it over. No cam yet, just crank and 4 pistons. Before installing any pistons I'm able to spin the crank with very little effort. The 1st time I began installing the pistons it pretty much locked up after 2 pistons were installed. I removed them and started over and this is where I'm at so far. Something seems to be binding up the rods I'm guessing. 350 bored 30 over and rings are gapped at .019.
 

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kj,
If you only install 1 piston and rod how is it ?

Can you move the big end of the rod back and forth on the crankshaft ? They should move very easily.

Which 4 pistons and rods have you installed so far ? All on one side ?
 

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Discussion Starter · #6 ·
kj,
If you only install 1 piston and rod how is it ?

Can you move the big end of the rod back and forth on the crankshaft ? They should move very easily.

Which 4 pistons and rods have you installed so far ? All on one side ?
When I take them back out I will see if they slide on the crank freely. I have the rear 4 installed so far.
 

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I don't believe so. They don't just flop around, but they move easily.
When you check the rod bearing clearance be sure chamfered edge of the rod is facing the outside of the crank journal. Not even sure could assemble it that way but worth checking.
 
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It sounds like you have the rods in the wrong position. The little "tangs" that locate the rod bearing should be facing out towards the outside of the block, not in towards the camshaft.
 

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Here is a picture. A little hard to see but this is how they should be oriented. Make sure that the arrows or notches on the pistons are pointing to the front of the engine.
 

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Discussion Starter · #11 ·
Ok, I'll have to check the "tang" position you're talking about. The way I went about determining the orientation of the rods is they are slightly off center so there's a large lip on one side than the other. Looking at that I placed the rods with the smaller lips towards each other so they are more centered... if that makes sense. But I will check everything you guys have mentioned so far and get back to the thread in a day or two. Thanks for everything so far.
 

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KJ,
Are your rods numbered ?? Chevy does not number them from the factory but I always put numbers on them when I swap pistons for a customer. Makes it much easier. The numbers are on the same side of the rod as the bearing tangs so you can see them when the engine is together.
 

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Discussion Starter · #13 ·
They are not numbered and everything has been shuffled around in the garage a few times. So I'm certain they are not going in the same cylinders they came out of. That's one thing that has been on my mind a lot lately.
 

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KJ,
Just want to add one more thing. Are you pretty sure that all of the caps are on their correct rods ? You said that they had been shuffled around in the garage.
 

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Discussion Starter · #15 ·
The caps are numbered, the rods are not. My best answer is caps are in the correct spots, it's a crap shoot on the rods and pistons. And I see where you're going with this. If the caps aren't matched up with the original rods some could be pinching the crank, correct?
 

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Kind of unusual for just the caps to be numbered. They absolutely have to go on the correct matching rod. If there is any question about it you really need to make sure. Its not real hard to match them up but a little time consuming. First of all make sure that the rods are not numbered. If they are not then I will try to talk you through making sure they are matched. I am pretty swamped here at the shop today but might take a few pictures later on to show you how to do it.
 

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Discussion Starter · #17 ·
I have a very strong feeling this is my issue, of not my only issue at least my main issue, and I would greatly appreciate the help on that.
 

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My 69 Camaro 350 was built to tight specs and it took 70lbs to crank over the short block. I called my very reputable builder and he said do not worry unless it goes over 85. That engine ran great for 20 years
 
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