Magnum 5.9L vibration

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Achill

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Hi, have a Dart 1968, made an engine swap to 5.9 Magnum, transmission is 727. torque converter is TCI, after several attempts with the wrong flexplate installed the right one, (B&M SMALL BLOCK FLEXPLATE BALANCED TO MATCH CHRYSLER 5.9 COUNTERWEIGHT), with zero effect, (suppose that because of big vibration that distributes across the body the small vibration caused by wrong flexplate was not noticeable) I'm puzzled where to look for. Sparks replaced with the new ones - zero effect, photo of sparks attached. Compression in green zone, equal. Carb, intake, distributor, wires, torque converter, transmission - new ones. Tomorrow planned to remove the front damper (DAMPER, MAGNUM 5.9 EXT BALANCE) and check if it will change the situation.

Engine was disassembled from the beginning.

Where to check? any exactly this engine specifics (besides it's externally balanced)?
what's the checklist to kill vibration?
1. Sparks
2. Wires
3. Distributor?
4. Front damper?
5. Special way to assemble crankshaft? Pistons?

PHOTO-2020-10-10-14-54-22 (1).jpg
 
If the engine is externally balanced you need to have the externally balanced damper. Without it the engine will vibrate. 65'
 
Plymouth 65 said:
If the engine is externally balanced you need to have the externally balanced damper. Without it the engine will vibrate. 65'
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that I know, and I have the front damper (as it's stated in original post) and the specially balanced flexplate
 
I had a motor that had 4 spd dowell pins in it and had a vibrition with auto tranny on it. Drove me nuts figuring that out.
 
Kendog 170 said:
I had a motor that had 4 spd dowell pins in it and had a vibrition with auto tranny on it. Drove me nuts figuring that out.
Click to expand...
Can you please explain a bit more? Did I get it correct that one of the reasons that my engine and transmission are not centered vs each other? Or?
 
Achill said:
Hi, have a Dart 1968, made an engine swap to 5.9 Magnum, transmission is 727. torque converter is TCI, after several attempts with the wrong flexplate installed the right one, (B&M SMALL BLOCK FLEXPLATE BALANCED TO MATCH CHRYSLER 5.9 COUNTERWEIGHT), with zero effect, (suppose that because of big vibration that distributes across the body the small vibration caused by wrong flexplate was not noticeable) I'm puzzled where to look for. Sparks replaced with the new ones - zero effect, photo of sparks attached. Compression in green zone, equal. Carb, intake, distributor, wires, torque converter, transmission - new ones. Tomorrow planned to remove the front damper (DAMPER, MAGNUM 5.9 EXT BALANCE) and check if it will change the situation.

Engine was disassembled from the beginning.

Where to check? any exactly this engine specifics (besides it's externally balanced)?
what's the checklist to kill vibration?
1. Sparks
2. Wires
3. Distributor?
4. Front damper?
5. Special way to assemble crankshaft? Pistons?

View attachment 1715611442
Click to expand...
Magnum 360 and LA 360 use different weighted flex plates.
 
I ran a stock bottom end 5.9 Magnum, and had to run the stock 5.9 Externally balanced harmonic balancer, which it sounds like you are, and the stock 5.9 Magnum flex plate with one of the torque converter bolt holes slightly elongated to mate with the converter. Not sure how you balanced a non-5.9 Magnum flex plate, but I'd suspect that.

You must also run a neutrally balanced torque converter with the above mentioned items. Some of the factory LA converters were externally balanced too I believe.
 
mopar65 said:
Magnum 360 and LA 360 use different weighted flex plates.
Click to expand...
I know. I used the special flex plate. No doubts I have the correct one. I’ve passed the long way to it, thru 10360, 10237 etc.
 
jbc426 said:
I ran a stock bottom end 5.9 Magnum, and had to run the stock 5.9 Externally balanced harmonic balancer, which it sounds like you are, and the stock 5.9 Magnum flex plate with one of the torque converter bolt holes slightly elongated to mate with the converter. Not sure how you balanced a non-5.9 Magnum flex plate, but I'd suspect that.

You must also run a neutrally balanced torque converter with the above mentioned items. Some of the factory LA converters were externally balanced too I believe.
Click to expand...
Torque converter is TCI-141500, wich is having neutral balance I believe.
 
Achill said:
I know. I used the special flex plate. No doubts I have the correct one. I’ve passed the long way to it, thru 10360, 10237 etc.
Click to expand...
Wear did you find the B&M magnum flex plate at? Because B&M doesn't make them no more. I havent been able to find one.
 
I've passed long way to get the right flexplate Flexplate is not fits the torque converter
Factory magnum flywheel discontinued, only ATP-Z332 (or close) is available, but it's having 10` bolts, I have 11`. And yes, Hughes modifying it for 200$ because there no other options.
 
oldkimmer said:
Well then if u still have a vibration maybe Hughes didn’t do it right. Kim
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Looks like vibration is stronger, and does not changed after 3 different flywheels changed. I suppose it's coming from the torque converter or from somewhere else...
66fyssh said:
One like this. Picture came from another thread on FABO. I used a factory one like this on the 5.9 I built. No problems.

View attachment 1715611976
Click to expand...
I have it, it's smaller (10`) bolt circle.
 
Achill said:
Looks like vibration is stronger, and does not changed after 3 different flywheels changed. I suppose it's coming from the torque converter or from somewhere else...

I have it, it's smaller (10`) bolt circle.
Click to expand...
Hi. Not trying to sound like a smart ***. But you do know that you have to file one of the bolt holes to get a after market converter to work with the stock magnum flex plate. I had to do that to get my 8 inch coan converter to fit my 2000 360 magnum engine
 
mopar65 said:
Hi. Not trying to sound like a smart ***. But you do know that you have to file one of the bolt holes to get a after market converter to work with the stock magnum flex plate. I had to do that to get my 8 inch coan converter to fit my 2000 360 magnum engine
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Absolutely! I have it, I know that torque converters could have different bolt pattern (diametr). Stock one, Atp-z332 is 10 inch bolt pattern, I have 11 inch torque converter, and I’ve tried to install different ones, with zero result. I have massive, heavy “circle” vibration, looks like my torque converter is having heavy disbalance. I have it new but could be the case it’s not filling with the oil correctly? I’ve read this in reviews for b&m but looks like it’s the case for my tci.
 
Achill said:
Absolutely! I have it, I know that torque converters could have different bolt pattern (diametr). Stock one, Atp-z332 is 10 inch bolt pattern, I have 11 inch torque converter, and I’ve tried to install different ones, with zero result. I have massive, heavy “circle” vibration, looks like my torque converter is having heavy disbalance. I have it new but could be the case it’s not filling with the oil correctly? I’ve read this in reviews for b&m but looks like it’s the case for my tci.
Click to expand...

First would like to say sorry for all the problems you are having. I have never heard or have had a converter not fill up all the way. Making it out of balance. Make sure your converter bolts are tighting all the way. They maybe to long or your converter lug threads not deep enough and the bolts are bottoming out before they are tight. Also make sure your front pump bushing is not worn out
But to me if it was worn out enough to make it vibrate that bad. That your pump seal woukd be leaking
 
mopar65 said:
First would like to say sorry for all the problems you are having. I have never heard or have had a converter not fill up all the way. Making it out of balance. Make sure your converter bolts are tighting all the way. They maybe to long or your converter lug threads not deep enough and the bolts are bottoming out before they are tight. Also make sure your front pump bushing is not worn out
But to me if it was worn out enough to make it vibrate that bad. That your pump seal woukd be leaking
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thanks! Several facts:
1. Plugs working, all. checked.
2. Distributor new, the cap is ok.
3. Flexplate change, from non balanced (no counterweight) for Magnum to 10236, 10237, Magnum balanced by hughes engine does not affect much the vibration, it's heavy, the doors maps (panels) are shaking on low and 1500-2000 rpm.
4. Transmission, torque converters are new

what else? I started to think to swap my torque converter and flexplate to the smaller bolt circle torque converter to install the stock flex plate (10 inch).
 
I had a motor that had 4 spd dowell pins in it and had a vibrition with auto tranny on it. Drove me nuts figuring that out.

Achill said:
Can you please explain a bit more? Did I get it correct that one of the reasons that my engine and transmission are not centered vs each other? Or?
Click to expand...

If the motor your using was originally a stick car and you just bolted an auto to it it will vibrate. My vibration wasn't bad a low rpm though. Just a thought and yes maybe not centered with eachother. I only say it cause it happened to me.
Hope you figure it out.
 
mopar65 said:
First would like to say sorry for all the problems you are having. I have never heard or have had a converter not fill up all the way. Making it out of balance. Make sure your converter bolts are tighting all the way. They maybe to long or your converter lug threads not deep enough and the bolts are bottoming out before they are tight. Also make sure your front pump bushing is not worn out
But to me if it was worn out enough to make it vibrate that bad. That your pump seal woukd be leaking
Click to expand...

This same thing happened to me. Good Point. Glad you reminded me ! On my first go around I found one of the bolt holes in my new TC that wasn't deep enough so I had to fix that, and IIRR the manufacturer { Turbo Action }said I would have to change the front bushing.
This new TC used larger bolts, but that was no problem since the B&M Magnum flexplate was made for them. So I bought the bolts from TA, the HEADS were SHAVED-for a close fit, but I forgot the Locktite. I need all the help I can get.
These cars are one Giant frustrating Puzzle to me. Love it !
You guys on here help me more than you will ever know and I appreciate it!
 
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Is the pilot bearing the correct size for the transmission? I've had some vibration when I made that mistake in the past.

When I put my 5.9 magnum together I used the magnum flex plate and filed a hole for my neutral balance torque convertor that came off my old 318. I then bolted up my 904 and it all went well.
 
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