Jan 1st, 00, 10:37 AM
My name is Iwan and I recently swapped the straight 6 engine in my '78 Camaro for a 454 V8. After my first test drive I was totally shaked from all the vibrations in the car. The 454 engine is a '76 pick up engine bored 0.030" over and was rebuilded by myself. The vibration is a teeth rattling one which also occurs wenn the car is not moving (getting much stronger if the car is moving). My first guess was that the combustion in 1 or 2 cilinders was not as it should be, but the compression ratio testing and the ignition testing did not reveal any problems there. My second guess was while the car was already shaking before I swapped the engines (not as strong as it did now but still it was shaking) that it was a converter/transmission problem. After changing these both for different ones I have to conclude this wasn't the problem either. I my oppinion this means the unbalance must be generated in the motor itself which brings me finally to my questions.
Can this teeth rattling vibration been caused by putting on a wrong damper (the damper I put on after rebuilding was not the damper which belonged to this motor), if so, how can I identify a damper and check of this is a correct one?
Is this engine an internally balanced or an externally balanced one and what is the difference.
If you don't believe this strong vibration is caused by putting on a wrong damper what would be the next step to check (I'm running out of ideas).
Greetings from a vibrated dutchmen.
Jan 1st, 00, 01:56 PM
The 454 motor is externally balanced and requires a particular damper and flywheel. The damper can be identified by a cutout area in the back of it that makes it out of balance. If it is perfectly round, it is probably from a 396 or 427 and will not work. The flywheel must have a weight on it and must be the correct one for a 454. A 400 small block flywheel has a weight, and will bolt on but will not be correct, also causing a vibration. Which flywheel did you use ??? Where did the damper come from ???
You can e-mail any other questions and I will try to help.
Advanced Automotive Machine
[This message has been edited by BillK (edited 01-01-2000).]
Jan 2nd, 00, 05:43 AM
Thank you Bill for this quick reply.
The flywheel I put on was a new one I bought specially for a 454 engine (it also shows the extra weight on it). The damper I jused came of a '84 454ci K30 pickup engine, I did not check if it was perfectly round or not. The damper originally belonging to the engine I build in the Camaro was a smaller one and looks perfectly round to me (I had to change dampers because I could not make a matching set of pulleys with the old damper)
I also collected some numbers perhaps this can help you to identify my (the cars) problem.
The numbers of the '76 Big Block I put in the Camaro: T0413T8 (stamped in the engine)
361959 (forged in the engine).
The numbers of the '84 Big Block from which I took the damper: T0622UBC (stamped in the engine) E4015445 (forged in the engine)
The number on the originally damper for the engine I put in the Camaro: 364720 (note: this is not the damper currently jused)
Jan 2nd, 00, 09:41 AM
I had a bizarre vibration show up on an otherwise good motor. Turned out the bellhousing bolts somehow loosened up???? and the engine was shaking around the trans shaft. It did a real destructo job on the pilot bushing but went away when the bolts were tightened.
Might be something to check since the vibration was in the car prior to the new motor.
Jan 3rd, 00, 02:49 PM
The 84 damper should be ok. All the 454 dampers are basically the same. The flywheel should also be ok as long as you purchased it for an 84 motor. The 454 flywheels changed around 1991 when they went to the one piece rear main seal.
Did your crankshaft have a pin in it to correctly locate the flywheel ? It is pretty rare to see a 454 without the pin, but I have seen them. If the pin is not there, the flywheel could be in the wrong position.
The next thing I would be doing is removing all the belts (water pump, alternator etc) and run the motor for a few minutes. As long as you dont get real carried away with revving it up, you can run it at least 5 minutes like this without causing any damage. If the vibration goes away, start looking at the fan, water pump, alternator etc as the cause.
The next test would be to remove the flywheel dust shield, unbolt the torque converter and pull it back away from the flywheel. You can run the motor like this without causing any damage. If the vibration goes away, the problem is in the converter or trans.
By the way, solid motor mounts, or bad rubber mounts can also make a bad vibration. Also make sure nothing from the motor, such as an exhaust pipe, is hitting anything under the car.
Hope this helps,
Advanced Automotive Machine