360 Balance Question

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Aaron

Aaron

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Fortuna, California
I get a vibration in the steering at 40mph and and at other speeds above that.
I think the 727 and 360 in my duster were split and now the external balance on the torque convertor is off. Is it possible the flex plate and convertor were not marked when they were removed and installed and now are in a different configuration?

I had a shop remove the 360 and 727 from my wrecked charger and put it into my duster. Well after lots time work, I have the car moving again (they just dropped the engine in for me, I did most everything else). They closed shop about 6 months ago and I cannot get ahold of them to find out what they did.

If the convertor balance weight is my problem, what can I do to fix this? Do I need to remove the tranny or engine (I currently lack the equipment to do the latter)?. Can I just un-bolt the converter and try it in a different position? Any information or details on how to fix this would be greatly appreciated.
Thank You
Aaron
 
Aaron said:
I get a vibration in the steering at 40mph and and at other speeds above that.
I think the 727 and 360 in my duster were split and now the external balance on the torque convertor is off. Is it possible the flex plate and convertor were not marked when they were removed and installed and now are in a different configuration?
Click to expand...

No, the flexplate and converter will only go on one way, they are ever so slightly apart from lining up the holes, but will only fit one way.


I had a shop remove the 360 and 727 from my wrecked charger and put it into my duster. Well after lots time work, I have the car moving again (they just dropped the engine in for me, I did most everything else). They closed shop about 6 months ago and I cannot get ahold of them to find out what they did.

If the convertor balance weight is my problem, what can I do to fix this? Do I need to remove the tranny or engine (I currently lack the equipment to do the latter)?. Can I just un-bolt the converter and try it in a different position? Any information or details on how to fix this would be greatly appreciated.
Thank You
Aaron
Click to expand...

You can check if you have a balanced converter or not. If you remove the inspection plate on the transmission and turn the motor/converter around you should see a couple (usually 2) small block weights on the converter. Inbetween the mounting pads likely. If you do not have the weights, you might be able to see what flexplate you have, likely there is just a stocker 4star flexplate in there, but B&M also makes a balanced flexplate so you can run a neutral balance converter (no weights). You might possibly (though unlikely) have something like that.

Assuming you've concluded that the vibration isnt a motor mount? trans mount? wheel balance? alignment? u-joint? etc etc?

-Mike
 
Thank You for the quick reply Mike. I plan to rebuilt the suspension this holiday weekend and then get the wheel balance and alignment checked out. It could be a problem with the 32 year old suspension parts or something else. It could also be the trans mount or engine mounts, the trans mount hasnt been changed but I think the engine mounts are solid ones. What engine and tranny mounts should I try if the suspension upgrade doesnt fix it?
 
Aaron said:
Thank You for the quick reply Mike. I plan to rebuilt the suspension this holiday weekend and then get the wheel balance and alignment checked out. It could be a problem with the 32 year old suspension parts or something else. It could also be the trans mount or engine mounts, the trans mount hasnt been changed but I think the engine mounts are solid ones. What engine and tranny mounts should I try if the suspension upgrade doesnt fix it?
Click to expand...


I would not run two solid motor mounts on a street car, not necessary..in my opinion. I choose to run a moroso solid drivers side mount and just a replacement rubber passenger side mount. The drivers side keeps it planted and from moving. Passenger side just absorbes vibrations, i did not have any new vibrations from the swap from two replacement mounts. Trans mount just a replacement will get the job done, polys are availible if you feel compelled to run one.

-Mike
 
If you have some way to get the vehicle on a hoist so the rear suspension hangs down, leave trans in neutral and rotate the rear tire/tires and watch the drive shaft as you turn them, you may have a bent or dented driveshaft and this would be the cheap free way to check it. Also look at the driveshaft close to the ends and see if there are any spots that look like a weight may have been knocked off. I spent a LONG LONG time searching for the cause of a vibration I was having that turned out to be a driveshaft that had been improperly shortened and was out of balance. If the driveshaft has a visible bend/warp/warble to it, replace it. If it's a missing weight, get it rebalanced.
 
If the motor and tranny where in your other car as a pair,and the car did not have a vibration then,and does now,you have a drive shaft diffy angle problem.Mopar torque convertors can only be installed one way,people have tried to install them wrong.If no weight was removed during the install,the vib is in the drive line.Look to see if the two weights are still there,one on either side of the drain plug in the convertor.You can buy a special flex plate to counter balance the convertor and remove the weights to use any convertor.You could have a bad drive shaft/pinion angle that is causing the vibration due to the install,Mrmopartech
 
vibration in the steeering is not likely to be in the drivetrain...you usually feel a driveshaft or whatever in the seat, not on the wheel...Id be looking at loose front end parts, out of round tire, wheel out of balance or a bent rim
 
On the motor mounts - if your car is a 73 or newer it has the captive spool type mounts - if the K frame is original to the car. You dont need solid mounts with this set up - its a failsafe design, unlike the old biscuit type used on the 72 and down cars. If the mounts are trashed replace the rubber inserts in the mounts themselves and you are good to go.
 
Well, as I said, I had a mad vibration, felt it in the steering, and it seemed like the sound couldn't ever be tracced to any one area. Lifted car on hoist, turned wheels watched driveshaft, It WAS the driveshaft. As soon as I replaced it with a new one I had made, vibration VANISHED. They are 30 plus years old uni-body cars and they flex, especially in the mid forward area which can transmit to the steering wheel. What I am suggesting him to check is free to be inspected with a jack and a few jackstands. :thumbrig:
 
66dartgt said:
On the motor mounts - if your car is a 73 or newer it has the captive spool type mounts - if the K frame is original to the car. You dont need solid mounts with this set up - its a failsafe design, unlike the old biscuit type used on the 72 and down cars. If the mounts are trashed replace the rubber inserts in the mounts themselves and you are good to go.
Click to expand...

Is it hard to change out the inserts in the mounts? The local parts store has the whole mount (right) for 9.99. And left for 11.99. Or the inserts are about 4 dollars. Can the new inserts be put into the mounts without removing it from the engine? I have TTI headers, will these be in the way very much? I also want to change the tranny mount while I am at it just to be sure (as mentioned above). By the way, the vibration got worse (I've rebuilt the suspension also since this thread started), and today while driving down the highway the driveshaft came off (rear u-joint broke). This is what is promting me to replace these. I am also going to have new u-joints installed in the driveshaft, and have it balanced and checked out. Are there any good articles or instructions for replacing the engine and tranny mounts for my Duster? Sorry for the long post.
Thank You
 
Aaron said:
Is it hard to change out the inserts in the mounts? The local parts store has the whole mount (right) for 9.99. And left for 11.99. Or the inserts are about 4 dollars. Can the new inserts be put into the mounts without removing it from the engine? I have TTI headers, will these be in the way very much? I also want to change the tranny mount while I am at it just to be sure (as mentioned above). By the way, the vibration got worse (I've rebuilt the suspension also since this thread started), and today while driving down the highway the driveshaft came off (rear u-joint broke). This is what is promting me to replace these. I am also going to have new u-joints installed in the driveshaft, and have it balanced and checked out. Are there any good articles or instructions for replacing the engine and tranny mounts for my Duster? Sorry for the long post.
Thank You
Click to expand...

my gues is that since your driveshaft came of because of the bad u joint you may already have found your vibrationproblem, on your question about replacing motormounts there is noway you will beable to change just the inserts without removing the mount from both the k frame and the engine, easiest way to replace the mounts is to unbolt your headers from cylinderheads (this will alow you to move the engine around some more) then with a with a floorjack and a big block of wood under the oilpan loosen the bolts thru the spoolmounts and then loosen the bolts going thru the mountingears on the engineblock then slightliy raise the engine with the floorjack and you will be able to get your motormounts out, it can be done with a motorlift also.. not realy hard to do but make sure the engine is safely lifted so you dont hurt yourself.. it takes some time but is possible :)
 
Thank You for the reply. Furthur inspection shows the tranny mount is COMPLETELY thrashed, and the tranny looks like its not in straight. I'm not completely shure, but either the engine mounts wore out that cause the tranny mount problem, or its the other way around. I will just buy the whole mounts as they are pretty cheap any-ways ~28 dollars for the whole set. Thank you for the instructions, the replacement looked pretty straight-forward, but I just wanted to be sure.
 
And the out come of the driveshaft inspection/balancing? Bad driveshaft/u-joints can cause premature wear of trans mount, but sounds to me like just plain old worn out original mounts, I am betting the shop you had do the job probably didn't replace them when they did the swap. Bad engine mount bushings would also expidite the failure of the trans mount bushing. You also need to take a close look at your pinion angle as that is/can and usually does cause failure of a rear u-joint (I am speaking from expierence). It is possible that just the bad engine mounts caused the trans mount to fail and in turn caused a bad pinion angle which may all be fixed by replacing the mounts but it never hurts to be sure and checking the pinion angle is relativly cheap/free if you have the right tools.
 
I will be sure to check the pinion angles and all after I get the driveshaft fixed. There is only ONE place that does driveshafts locally, and I have not heard good things about them from other mopar owners. Are there any good custom driveshaft places that I can order one from maybe? My driveshaft came out of a 74 b-body car, and was re-sized to fit. Should I just keep this one and take my chances? I can post pics of the driveshaft if needed (it looks like its two different diameters/sizes fit together). BTW my new mounts arrived, the old ones look even more worn out after looking at the new ones. The rubber isolators are almost completely gone on the old mounts!
Thank You
 
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