Hard turning of 408 stroker
Hard turning of 408 stroker 
So here is my issue I have the engine mounted on the k-memeber and when I go to turn it with the torque bar attached to the balancer bolt It takes every thing I got to turn it. I'm 260lbs and it damn near kills me to push down on it. It will move but it's so hard to move it. Every thing has 10w30 oil to lube it up. And all the clearances were between .024 and .027 and the rod caps all lined up and all the rod clearances were like .025 so Every thing is what tsp said to try for. But i just can't turn this damn thing over without dying. I'm afraid to turn it over by the starter because it may break my flex plate. Any ideas what it could be or is this normal? The engine is fully dressed but without the trans attached and the spark plugs are out. My cam is a 244/248 .615 with .700 Springs and 7.575 pushrods.
If I were you, I would start disassembling the engine in stages and see where the hang up is. Start with removing the accossories and see if it helps. If not, remoe the rocker arms, then the cam, and if it’s still hard to turn, start pulling pistons one at a time. The rotating assembly shouldn’t need more than 20ft-lbs to rotate.
When it was just the pistons crank and rods it rotated decently fine then I started to had the heads and all that stuff and it was damn near impossible. The crank itself rotated pretty freely without issues. And the added the pistons and got harder but not like this...someone said about 80ftlbs to turn it over. Idk if that's right or not.
Remove the drive belt and spark plugs and see if it gets easier to turn over by hand. If that doesn’t help then disassemble like KCS recommended, methodically so you can pinpoint any binding.
Sounds like the short block is good. Do you know the static compression ratio? Did you verify piston to valve clearance?
Sounds like the short block is good. Do you know the static compression ratio? Did you verify piston to valve clearance?
Remove the drive belt and spark plugs and see if it gets easier to turn over by hand. If that doesn’t help then disassemble like KCS recommended, methodically so you can pinpoint any binding.
Sounds like the short block is good. Do you know the static compression ratio? Did you verify piston to valve clearance?
Sounds like the short block is good. Do you know the static compression ratio? Did you verify piston to valve clearance?
Last edited by Philhippy45; Sep 7, 2018 at 11:33 AM.
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FWIW, I’ve seen a situation where a customer brought their car into a mechanic thinking the engine was seized and was fully prepared to fork out the money for a new engine. The mechanic determined the problem was actually a seized up AC compressor. The compressor was replaced and the problem was fixed.
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Verdad Gallardo FWIW, I’ve seen a situation where a customer brought their car into a mechanic thinking the engine was seized and was fully prepared to fork out the money for a new engine. The mechanic determined the problem was actually a seized up AC compressor. The compressor was replaced and the problem was fixed.
thats what fwiw means lol. Hmm Idk what it could be I dont see how anything is hanging up I dont hear anything or really feel anything scraping just tight then loose then tight and then stays pretty good unless I let it sit awhile then tight again.
Tight then loose then tight again sounds like you could just be fighting the forces of cylinder compression. At 11.5:1 with new rings and heads I would expect it to be hard to turn by hand. If you can get it to turn 2 full crank revolutions without binding then you should be good to go. I would still take the acc drive belt off to reduce drag from the alt and water pump.
If you’re concerned about lubrication you could also use (or make) a remote oil pump and pre-lube the engine before cranking it. Some like to just lube by cranking the engine but not starting/running it, but a remote oiler will get fresh oil to the bearings before any cranking.
If you’re concerned about lubrication you could also use (or make) a remote oil pump and pre-lube the engine before cranking it. Some like to just lube by cranking the engine but not starting/running it, but a remote oiler will get fresh oil to the bearings before any cranking.
If your 260lbs, and the plugs are out, and it just about kills you to turn it over with a breaker bar, something is wrong.
Are you sure PTV is good? How did it turn over for you when you checked PTV?
Unless your exaggerating big time, I would pull it back out and disassemble.
Are you sure PTV is good? How did it turn over for you when you checked PTV?
Unless your exaggerating big time, I would pull it back out and disassemble.
If your 260lbs, and the plugs are out, and it just about kills you to turn it over with a breaker bar, something is wrong.
Are you sure PTV is good? How did it turn over for you when you checked PTV?
Unless your exaggerating big time, I would pull it back out and disassemble.
Are you sure PTV is good? How did it turn over for you when you checked PTV?
Unless your exaggerating big time, I would pull it back out and disassemble.
Tight then loose then tight again sounds like you could just be fighting the forces of cylinder compression. At 11.5:1 with new rings and heads I would expect it to be hard to turn by hand. If you can get it to turn 2 full crank revolutions without binding then you should be good to go. I would still take the acc drive belt off to reduce drag from the alt and water pump.
If you’re concerned about lubrication you could also use (or make) a remote oil pump and pre-lube the engine before cranking it. Some like to just lube by cranking the engine but not starting/running it, but a remote oiler will get fresh oil to the bearings before any cranking.
If you’re concerned about lubrication you could also use (or make) a remote oil pump and pre-lube the engine before cranking it. Some like to just lube by cranking the engine but not starting/running it, but a remote oiler will get fresh oil to the bearings before any cranking.
If not already done, pull the starter and try. If not, kcs advice in second post is best. Take rockers off and see if it improves. If it does, verify cam timing. If it checks out, time to flycut.
What bore is it and what bore head gaskets did you use?
You said it was good until the heads went on...
First thing to try is pull the belt back off and see if it helps. Buddy of mine had a LS6 swapped rx7 and one day it wouldn't start, we tried push starting it but it kept locking up the wheels on the car because one of the pulleys on the motor was seized up.
You could also yank the rocker arms off real quick and see what it does
You said it was good until the heads went on...
First thing to try is pull the belt back off and see if it helps. Buddy of mine had a LS6 swapped rx7 and one day it wouldn't start, we tried push starting it but it kept locking up the wheels on the car because one of the pulleys on the motor was seized up.
You could also yank the rocker arms off real quick and see what it does
What bore is it and what bore head gaskets did you use?
You said it was good until the heads went on...
First thing to try is pull the belt back off and see if it helps. Buddy of mine had a LS6 swapped rx7 and one day it wouldn't start, we tried push starting it but it kept locking up the wheels on the car because one of the pulleys on the motor was seized up.
You could also yank the rocker arms off real quick and see what it does
You said it was good until the heads went on...
First thing to try is pull the belt back off and see if it helps. Buddy of mine had a LS6 swapped rx7 and one day it wouldn't start, we tried push starting it but it kept locking up the wheels on the car because one of the pulleys on the motor was seized up.
You could also yank the rocker arms off real quick and see what it does
