[C2] '63 SWC Engine Issues
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'63 SWC Engine Issues
Well, I am stumped. In my 63 the engine is a later year block with the casting number of 3970010. From what I can find that could be a 327 or 350. I have two questions, how do I determine which cu. in. displacement it is. Secondly, and more important the engine vibrates (really vibrates) when I speed in up (in neautral - 4 speed) I have checked the harmonic balancer and it seems ok. One thing I noticed is that the water pump pulley, aletrnator pulley and damper pulley are not parallel. The water pump pulley seems to be further out towards the front of the car which causes the belt to be crooked???
I do intend to swap motors when I can find a 327/340hp year appropriate engine. Unfortunately, my friend who GAVE me the car passed away and I have no idea from whom he purhcased it.
Any help is grealy appreciated.
Thanks,
Peter
I do intend to swap motors when I can find a 327/340hp year appropriate engine. Unfortunately, my friend who GAVE me the car passed away and I have no idea from whom he purhcased it.
Any help is grealy appreciated.
Thanks,
Peter
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From: I'm not doing as well as I expected, but I never expected I would
So many things. You might start with the pulley problem, check your clutch/pressure plate. Post your engines casting date. And the pad info. Pics when you get them.
Last edited by hedgehead; Aug 13, 2017 at 04:34 PM.
Melting Slicks
Joined: Jan 2010
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From: Woodland Hills CA
Engine
Dont worry about what cu in it is. The only way to deterime that is with a full teardown and see what kind of parts are in it now. It could even be a 383, you just dont know. Fix the vibration and enjoy your friends memory with the car. In addition to the belt being off set, look for pulleys out of round.
Team Owner
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From: Washington Michigan
Well, I am stumped. In my 63 the engine is a later year block with the casting number of 3970010. From what I can find that could be a 327 or 350. I have two questions, how do I determine which cu. in. displacement it is. Secondly, and more important the engine vibrates (really vibrates) when I speed in up (in neautral - 4 speed) I have checked the harmonic balancer and it seems ok. One thing I noticed is that the water pump pulley, aletrnator pulley and damper pulley are not parallel. The water pump pulley seems to be further out towards the front of the car which causes the belt to be crooked???
Peter
Peter
You may have a mis-match of pulleys and a "long" water pump, which will require replacement.
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About seven million 3970010 blocks were cast from late 1969 through 1979 - it was introduced along with the new "long" water pump accessory drive system in 1969 that moved the alternator to the passenger side (only on passenger cars and trucks, not on Corvettes). Externally, you can't tell whether it has a 3.00" crank (302), 3.25" crank (327), or 3.48" crank (350) unless you can see the shape of the flywheel flange on the crank or if the front pad stampings are readable. Otherwise, you have to tear it down and see what pistons and crank are in it (rods are all 5.7").
You may have a mis-match of pulleys and a "long" water pump, which will require replacement.
You may have a mis-match of pulleys and a "long" water pump, which will require replacement.
Team Owner
Joined: Mar 2003
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From: Greenville, Indiana
Don't you think you're jumping the gun a little?
First thing to do is take the fan belt off and run the engine and see if the vibration goes away. Then, report back what you find and what pump is on your engine.
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From: Cottonwood AZ
C1 of Year Finalist (performance mods) 2019
Yes, you need to address the mis-aligned pulleys but they are not going to cause a vibration.
There are many things that can cause vibration such as a misfiring engine. Since you don't seem to know much about the cars engine, my first real concern is weather the engine is internally balanced or externally balanced. The balancer would need to be a neutral type if it is externally balanced with the correct balanced flywheel. You don't want to run and rev the engine much if this engine is not balance properly as it could cause some serious damage.
There are many things that can cause vibration such as a misfiring engine. Since you don't seem to know much about the cars engine, my first real concern is weather the engine is internally balanced or externally balanced. The balancer would need to be a neutral type if it is externally balanced with the correct balanced flywheel. You don't want to run and rev the engine much if this engine is not balance properly as it could cause some serious damage.
Pro
Joined: Nov 2006
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From: Abington Pa
Well, I am stumped. In my 63 the engine is a later year block with the casting number of 3970010. From what I can find that could be a 327 or 350. I have two questions, how do I determine which cu. in. displacement it is. Secondly, and more important the engine vibrates (really vibrates) when I speed in up (in neautral - 4 speed) I have checked the harmonic balancer and it seems ok. One thing I noticed is that the water pump pulley, aletrnator pulley and damper pulley are not parallel. The water pump pulley seems to be further out towards the front of the car which causes the belt to be crooked???
I do intend to swap motors when I can find a 327/340hp year appropriate engine. Unfortunately, my friend who GAVE me the car passed away and I have no idea from whom he purhcased it.
Any help is grealy appreciated.
Thanks,
Peter
I do intend to swap motors when I can find a 327/340hp year appropriate engine. Unfortunately, my friend who GAVE me the car passed away and I have no idea from whom he purhcased it.
Any help is grealy appreciated.
Thanks,
Peter
So, just to be clear, the car is not moving and the engine vibrates in neutral at high RPM?
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63 Long Water Pumo
About seven million 3970010 blocks were cast from late 1969 through 1979 - it was introduced along with the new "long" water pump accessory drive system in 1969 that moved the alternator to the passenger side (only on passenger cars and trucks, not on Corvettes). Externally, you can't tell whether it has a 3.00" crank (302), 3.25" crank (327), or 3.48" crank (350) unless you can see the shape of the flywheel flange on the crank or if the front pad stampings are readable. Otherwise, you have to tear it down and see what pistons and crank are in it (rods are all 5.7").
You may have a mis-match of pulleys and a "long" water pump, which will require replacement.
You may have a mis-match of pulleys and a "long" water pump, which will require replacement.
Thanks much for your help,
Regards,
Peter
Team Owner
Joined: Mar 2003
Posts: 26,118
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From: Greenville, Indiana
The 608 should work fine on your engine.
Read this thread for a possible issue on your engine concerning pump shaft size and fan clutch hub size.
https://www.corvetteforum.com/forums...lutch-fan.html
If you don't find anything here, you can remove the fan blade, install the fan bellt and see if the vibration is still gone. You may have an out of balance fan blade.
I can't see your pictures so this is all I can tell you.
Read this thread for a possible issue on your engine concerning pump shaft size and fan clutch hub size.
https://www.corvetteforum.com/forums...lutch-fan.html
If you don't find anything here, you can remove the fan blade, install the fan bellt and see if the vibration is still gone. You may have an out of balance fan blade.
I can't see your pictures so this is all I can tell you.
Last edited by MikeM; Aug 22, 2017 at 05:33 PM.
Thread Starter
Advanced
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The 608 should work fine on your engine.
Read this thread for a possible issue on your engine concerning pump shaft size and fan clutch hub size.
https://www.corvetteforum.com/forums...lutch-fan.html
If you don't find anything here, you can remove the fan blade, install the fan bellt and see if the vibration is still gone. You may have an out of balance fan blade.
I can't see your pictures so this is all I can tell you.
Read this thread for a possible issue on your engine concerning pump shaft size and fan clutch hub size.
https://www.corvetteforum.com/forums...lutch-fan.html
If you don't find anything here, you can remove the fan blade, install the fan bellt and see if the vibration is still gone. You may have an out of balance fan blade.
I can't see your pictures so this is all I can tell you.
Thanks.
Team Owner
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Posts: 38,897
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From: Washington Michigan
Race Director
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From: Central Arkansas
I don't know how much misalignment of pulleys you have, but when installing the new water pump you can test fit it and the pulley and if it doesn't align perfectly - the hub on the water pump is a press fit and can be moved in with a press or vice and pulled out with a gear puller to slightly adjust.
