[Project NC]

Hello,
I'm having a issue with my 454 when it's at idle. The rpms on the tach shows it's idleing at about 650 but the engine feels like it's getting ready to jump out of the car. Besides that the engine is real strong. I took a chance and bought the motor from a local that had a ad on Craigslist. It was a fresh rebuild and i've put about 10 miles on it.It didn't have a flywheel so i took one from a 402 I had sitting in my garage but after reading a few posts i see that the 454 is externally balanced.
Am i using the wrong flywheel for my oem 454? The balancer is probably a internal one also.

 

[boz53bj]

402 is internally balanced and 454 is externally balanced.

 

[MEJ1990TM]

I would think if you put a internally balanced flywheel on an externally balanced engine it would be shaking like crazy all the time. You need to get it changed.

 

[Project NC]

Got it. I didn't know that and just started reading about it today. I'll get that changed this weekend. Thank you

 

[animal69]

You may have pounded the bearings out of it if you ran it much. I once built a 400 SBC for a guy's Blazer. I stressed to him the differences between internal and external balancing. Well about a year later he needed a clutch and flywheel so he took it to a small garage (hammer mechanics!). He told them it was a 400 and they said they knew what they were doing. Long story short, they used a 350 flywheel.He said it vibrated but he drove it anyway. When he brought it back to me to check out the bearings were gone, the crank was shot and it had to be completely rebuilt.
He ended up owning the idiot's business!

 

[Project NC]

Wow!!!
Hopefully that's not the case with me. It's my wifes Chevelle and she doesn't even drive it. I have other projects I'm working on and the engine has about 10 miles since I put it in over 6 months ago.
Everything will work out because I have to pull the tranny to replace the seal anyways.

Thanks for your input

 

[70-SS454]

I suspect it has bearing damage now too...

 

[Project NC]

I doubt it

 

[Tom Mobley]

not with 10 miles.

Is it shaking like an engine with a bad plug wire or more like vibrating, gets worse with RPM?

 

[Project NC]

It only vibrates at idle when in drive. When it's in park, it feels real good and smooth.

 

[Tom Mobley]

that's not a balance. it will feel like a buzzy vibration that get worse with RPM. A lot worse, like it's going to vibrate the fillings out of your teeth. You may have two problems. A mis-fire at low RPM, worse when loaded in gear and a vibration caused by wrong flywheel.