Engine vibrating?

**Street Fighter** · 04-08-2008, 03:34 AM

I hope that someone will be able to give me some Info on this problem.Maybe you engine builders will be able to help me. Is there anyway a engine can start virberating? I thought that it was in the balancer and replaced it but it stall does it, The engine have about 25,000 miles on it,I built it years ago and it has always ran fine until about a year ago.can anyone tell some of the things that will cost this problem? Need to add this is a 350 engine in a 77 camaro.

**96slow6** · 04-08-2008, 03:50 AM

Missfires are the biggest cause. How are the plugs, wires, ect. Are you sure the vibrations is from the engine and not the drive train.

**12pack** · 04-08-2008, 03:54 AM

I'm going to guess you have ruled out the drive train? How bad is the vibration? Does the engine rev ok or does it feel like it's being held back? What I'm trying to find out is it an ignition problem or a mechanical problem. It could be anything from a bad spark plug or wire to a broken crankshaft.
tell us more about the vibration does it do it all the time or at higher RPM's is the engine ran hard and what kinda parts do you have in ( stock or modified)
I'm leaning towards ignition

**Spaz** · 04-08-2008, 06:23 AM

checked your motor mounts? also it might not even be engine related... it could be some where in the drive line...

**PittZ28** · 04-08-2008, 08:58 AM

Originally Posted by Spaz

checked your motor mounts? also it might not even be engine related... it could be some where in the drive line...

x2 i was thinking the same thing g/l anyway on your quest

**Street Fighter** · 04-08-2008, 09:37 AM

Man I'm glad to see someone is trying to help me out.Ok the engine is bored 60 over with 10 to 1 flat tops,280 comp cam 480/480 lift, but I went with the 1.6 rockers which gave about a 510/510 lift.it has a RPM intake,Headers750 holley vac.and Iron vortec heads with a 525 max. lift.and a poineer fly wheel. A turbo 350 trans with a shiftkit.Now I have replaced the rearend,Changed axles,replaced rear drums,shocks,all frame and sup.brushens. Checked trans mount,replaced torque converter,Looked at motor mounts and tried raising RPMs to see if any movement of the engine none.The cars runs great no missing or anything like that,but at 55 mph you fell alittle viberation,than at 85 the hole car virberate so bad you can barely keep it in the road.Now I have had all wheels checked even put wheels on it from one of my other cars and the same thing.there is no stering wheel viberation just body. I have yet to have the driveshaft checked, but I see all weights on it and no dents on it.could it be in the Trans. everyone I talk to say there is no way the trans would last though that kind of viberating. I don't want to build or buy a engine and have the same problem. so you see I really need some ideals. I will be getting the drive shaft checked., but the guy that made it told me that if all weights and no dent's it is usually good. Also I have changed ujoints.

**Marc 85Z28** · 04-08-2008, 10:53 AM

Did both the old and new drums have weights on them? Most aftermarket drums do not, and will cause a vibration that behaves like a tire.

**12pack** · 04-08-2008, 01:17 PM

I thinking something to do with the Drive shaft? Are the ujoints in correctly? are the keeper in right. Some have inside c-clips and some have outside and some have both. At the rearend is it seated and not on the little tabs?

If you rev it up setting in the driveway to the RPM that your running at 85 MPH you have no shake? I'm trying to make sure the Torque Converter isn't out of balance.

**Street Fighter** · 04-08-2008, 06:35 PM

[QUOTE=12pack;1411232]I thinking something to do with the Drive shaft? Are the ujoints in correctly? are the keeper in right. Some have inside c-clips and some have outside and some have both. At the rearend is it seated and not on the little tabs?

If you rev it up setting in the driveway to the RPM that your running at 85 MPH you have no shake? I'm trying to make sure the Torque Converter isn't out of balance.[/QUOTE ------------------------ I talked to the guy that repaired my block and rods, he builds engines and repair heads. He told me that there was no way that the engine being a early 350 that it would have a balance problem,because that the balancing is all inside of the engine,and that there is zero balance on the outside of the engine,No weights any where.I had a converter that lost the weight off it so I got a new one, And no I don't think that there is any viberating at that Rpm. after talking to him and thinking about all the things I have done, but not the driveshaft because the maker told me it was more than likly good,I pulled it today and will be taking it to his shop tomorrow, I hope he fines something wrong with it.The rearend is setting flat on the pads but I don't like the way the ujoints looked today,they seem to move from side to side just abit when I tapped them with a pipe, I hope that he will tell me that the yoke is worn letting the joint move up and down putting the shaft out of balance.I'm hoping that something bad is wrong with the shaft so that I can really drive my car like I want with no viberating.Will let you all know what the guy fine on the shaft,They stay busy so it'll be monday or later before I know.Thanks to everyone that have and is still helping me find the cause of the viberating.

**Street Fighter** · 04-08-2008, 06:45 PM

Originally Posted by Marc 85Z28

Did both the old and new drums have weights on them? Most aftermarket drums do not, and will cause a vibration that behaves like a tire.

I didn't even notice if they did or not, but I will look tomorrow.The old drum had a weight that had come off so I got new ones, and like I said I did not notice the weights.thanks.