Vibration Problem

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WE BE BAD DART

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I have a real bad vibration in my 318 at 1500- 2500 rpms. The only thing that changed was I took the power steering pump and gear box off and replaced it with a manual one. I can bring the rpms up (while sitting still) and it will vibrate you out of the car. It seems to me something is out of balance. Please reply if anyone might know the solution.
Thanks

WE BE BAD DART
 
To get the PS steering box out you should have had to pull the motor off the K-Frame....are you sure you have the mounts fully seated back in the K-Frame ears?
 
Thanks for the quick response Dusterb318, Yes it is seated back where it should be. Do you think it could be the balancer? It would be strange for that to go out the same time I did the change over. This is really getting on my nerves.
 
Is it a stock balancer? Do you have a neutral weight flexplate and balancer on the engine? 318's came from the factory internally balanced. Stupid question but does the engine rev smoothly? Or does it have a "choppy" feel to it?
 
Yes it has a factory balancer and before I took the power steering off, I had no problem with any vibrations. The motor still revs fine, until you get to the rpms were the vibration is. I have put new motor mounts, new trans mount, new water pump, and still have the problem.
 
Very possible the balancer is bad.....the stockers are know to have the rubber deteriorate.......not gonna hurt anything to put another on there btu I hate to just throw parts at stuff.........Where did you get the new mounts from? They newest chinese mounts are really the best.....you might have a bad mount. Did you change the mount when you swapped the steering or did you change it to stop the vibration?
 
Is this a 4 speed car? The reason I ask is that I had the same kind of problem that you have. I checked everything up front on the motor and all was fine. But I ended up finding was my Centerforce pressure plate had 2 ball bearing work loose in the diaphram arms to throw things out of balance. I had to take the pressure plate completely loose, that's when the ball bearings fell out on the garage floor! It was a new clutch too! This may not be the case with your car My situation happened from one day to the next and got noticably worse over the next couple of days! One thing to try to eliminate it if it is up front is to disconnect the v belt or belts and start the motor and run it at those rpms where the vib comes in and see if it goes away. If you have multiple belts, you'll have to do one at a time to be sure of where it's coming from. That's how I knew to look to the rear of my 340 because nothing up front made any difference when connected or not.

Good Luck!
 
Thanks for the reply, it is a automatic and yes I did the same thing, taking the belts off. It made no difference at all.
 
The new mounts were put on after the vibration to see if that would cure the problem, but it didn't. Do you think it could be internal or could it be the balancer?
 
What I did was I took off the balancer and had it checked at the local machine shop just to rule it out. Mine was only out a couple of grams which is hardly noticble. Make sure there is no part of the engine thats in contact with any steering component or exhaust hitting any parts of the body. As long as your motor mounts are the rubber insolator type, they should isolate any small engine vibrations and not let them transfer to the car body.

Make sure that there isn't anypart of the exhaust system touching the frame up front. I had one spot that my headers were super close to the steering gear, so I had to do a minor crimp act at that one spot, but like I said, mine ended up being in the clutch. If you had everything disconnected up front and it still did it, the only thing turning at that point is the crankshaft balancer. If that checks out okay, then you need to look to the flexplate/torque converter area. That's the biggest external mass that's turning. If something is loose or come off, then that would show up as a vib. If all that is okay then you'll have to look at possibly internal engine issues.

Good Luck!
 
WE BE BAD DART said:
I have a real bad vibration in my 318 at 1500- 2500 rpms. The only thing that changed was I took the power steering pump and gear box off and replaced it with a manual one. I can bring the rpms up (while sitting still) and it will vibrate you out of the car. It seems to me something is out of balance. Please reply if anyone might know the solution.
Thanks

WE BE BAD DART
Click to expand...

try a new dist cap.

I cracked one on a Mopar, when jacking the motor to one
side, to change exhaust.

Drove me nuts.
 
Hey Cavemanmoron,
Thanks for your reply. I live in Forest Hill Maryland. I have a 72 Ply Valiant with a 318 cam, tunnel ram with two fours...runs pretty good for what it is. My son and I are building a 70 Duster BB 440 HP 455 rear 5500 stall, tubbed. Its at the machine shop now getting "fixed" 40 over, head work, new pistons..etc. If all goes well, it should be a 10 sec. carm Ill post some pics of both cars soon. I'm a new member and love this site. Everyone seems to be great here. I look forward to visiting this site quite often.

Thanks
Jerry
 
WE BE BAD DART said:
Hey Cavemanmoron,
Thanks for your reply. I live in Forest Hill Maryland. I have a 72 Ply Valiant with a 318 cam, tunnel ram with two fours...runs pretty good for what it is. My son and I are building a 70 Duster BB 440 HP 455 rear 5500 stall, tubbed. Its at the machine shop now getting "fixed" 40 over, head work, new pistons..etc. If all goes well, it should be a 10 sec. carm Ill post some pics of both cars soon. I'm a new member and love this site. Everyone seems to be great here. I look forward to visiting this site quite often.

Thanks
Jerry
Click to expand...


Best of luck with Both your toys,
and please keep us updated. Even a link to photos would work. ;)

Lee/cavemanmoron
 
Oldvart,
Thanks for the reply, at this point i'll try it. I don't know what else to check at this point. I'll keep you informed and let you know what happens.

Thanks,
Jerry
 
Check your trans mount I had the same problem after changing the engine. I must have broken it when raising up the engine. Replaced the mount and vibration gone.
Bruce
 
Thanks for all the replies, my last resort was to change the balancer and guess what? It was the harmonic balancer. Although it looked fine, that was where the vibration was.
 
Glad you found it. What kinda of Balancer did you get to replace it?
 
Hey Dusterb318
I had a balancer off a 340 sitting around, and I said what the heck, I'll try it. Sometimes you can't see the forrest for the trees.... We make things more difficult than it is.. I'm just glad to be up and running again. You can see the car its under my sons name dusterboyy440 (i think thats right) and also the 70 duster that we are putting together.
 
I think I'd be looking for an aftermarket balancer here in the future just to be on the safe side.....nice that you had one laying around to test it out.
 
I plan on changing my balancer soon before it goes out big time but don't know if the $100-$150 aftermarket are good or should I think about those $350 ones ?
 
I run a Summit brand SFI balancer and it has been fine for a bout 3 years now.....Jeg's also has a "house brand" balancer and I think either one would be fine. Of the $$$ money ones I'd look at Fluid Damper or ATI. IMO the Summit or Jeg's SFI balancer would be more than enough.
 
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