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Vibrations (318 to 360)

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bensinlukt

New member
Hi.
I have changed a 318 engine to a 360MLB. I was told everything would fit but apparently it didn't. Now I have problems with vibrations.
After switching damper the vibrations got reduced pretty much, but they are still there (it's a used damper though).
After some research I found out the flywheel should've been replaced as well, unfortunately I don't have one and have no idea of what I am looking for (the one I was suggested was way too expensive).
I was told I could re-balance my old 318 flywheel by drilling it and another one told me I might had to add weights (but I think this is for a turbine flywheel), is any of this possible?
I found some blueprints of drilling holes on a 318 flywheel to fit a 360 (here http://www.moparaction.com/tech/quest/internally.html) Would this help me?
Problem is, the picture says its the engine side of the flywheel (the picture faced aganst the engine I suppose?), but then the bolt holes doesn't match the crankshaft holes.
 
A good machine shop can re-balance your flywheel but it really needs to be done right. I had the same issue going from a 360 to an internally balanced 410, which is the reverse of what you're doing. It might be cheaper than buying a 360 flywheel but not by a huge amount. The difference is maybe $150, depending upon the rates your machine shop charges you. Easier to just buy a new flywheel. I didn't because the machinist was already doing other work for me. Hurrikain can get them for you and their prices are as good as anyones.
 
Thanks for the answer!
Now I got confused. When I look at this page http://www.hurrikain.com/Chrysler-Flywheels.htm, the 318 flywheel doesn't look at all like my current one.
The M360 though (part # 4417599), looks just like mine but with a big hole.
The part is currently out of stock, but I see its around $1000 cheaper than the one I was suggested to buy, even with the international shipment fees I suppose.
It gets expensive if its wrong, returning and shipment, because Im outside the US.

So Im still wondering whether the picture I found of drill holes (its three of them, not only one) are the right for re-balance the flywheel and if its possible doing this by myself?
I have acces to both tools and machines for this.
 
Whoa! Don't do a thing until you read this:

The 360 flywheel is NOT balanced, and deliberately: it's an externally balanced engine. The 318 is an internally balanced engine, so the flywheel IS balanced. You have to find a 360 marine flywheel for it.

Jeff
 
fastjeff said:
Whoa! Don't do a thing until you read this:

The 360 flywheel is NOT balanced, and deliberately: it's an externally balanced engine. The 318 is an internally balanced engine, so the flywheel IS balanced. You have to find a 360 marine flywheel for it.

Jeff
Click to expand...

But isn't it possible to remove the "balance/masses" from the balanced 318 flywheel? According to the site on first link in this thread you can read following;
"But why not just drill the 360 balance holes in the 318 flywheel? This is what the factory did! This trick works fine on any and all ferrous-metal flywheels (i.e., steel or iron), and the specifications on the drawing are correct for all '71-92 360s."
 
The 273/ 318 / 340's are all internally balanced engines ( not needing any external balancing ) The 360 is a externally balanced engine and NEEDS the special harmonic balancer / and flywheel and also the oil pan is different for the 360 from the rest of the family ( also the engine mounts are slightly different but you can shim them but that is just a small tidbit of info ) The issue you will find is that the 360 flywheels are very hard to find now days.. I had heard of a guy who used a weight plate that someone makes for a automotive application and used it and it worked well but I have not seen anyone use it personally.
 
Well the casting number on the flywheel comes back as a automotive flywheel with 130 teeth ( have the guy count them ) and depending on what drive / trans your using you need a 160 T ( Dana / velvet drive/ Chrysler 300 drive ) or if it is a Volvo drive it should be 142 T ( if I recall correctly ) .. what is behind the engine?
 
It's a Volvo Aquamatic 280, my flywheel got 122 tooths. The flywheel looking pretty much like the one greasemonkey linked to, but withouth four of the holes.

Still wondering if it's possible to sort this out by drilling those holes? Or what will happen?
I even have a pattern from the expensive flywheel, but these drill holes are located much further on the edge of the flywheel and they are smaller (logical).
 
You can buy unbalancing plates for SB Chevies (natch), but I'm not sure about Mopars. Try this site:

slantsixforum.com

Guys there know all there is to know about Mopars!

Jeff
 
In the car world the 318 is internally balanced and the 360 is externally balanced. Mopar does sell an external 360 balancing kit for torque converters. It consists of weights that come with a pattern on where to weld them on.
 
That might work, but finding a marine flywheel would be much easier.

Did you try M & M marine salvage? (They are on-line.)

Jeff
 
dynamax1709 said:
In the car world the 318 is internally balanced and the 360 is externally balanced. Mopar does sell an external 360 balancing kit for torque converters. It consists of weights that come with a pattern on where to weld them on.
Click to expand...

Yes, I've read about this before and it seems to work. But don't this work only on flywheels for automatic transmissions?

fastjeff said:
That might work, but finding a marine flywheel would be much easier.

Did you try M & M marine salvage? (They are on-line.)

Jeff
Click to expand...

Finding a flywheel isn't easy either (it seems). Especially when I'm not in the US; The reason why I am trying to drill my 318 wheel, and it seems way cheaper. Still got no answer if this would ever work though.
I will try mail M & M marine salvage, maybe they know what I am looking for?
 
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About 1999 or so chrysler changed the weight from the converter to the flex-plate on the 360 magnums. the imbalance is different from the early 360. The B&M plate has a notch missing out of it for the imbalance & is about 1/8" thick. Just use loctite on the bolts.
 
Its been a long time since this link has been active, I hope that your email address is still active. I just went from a LM318 to LM360 and ran into the same problem of the vibrations as you had my question to you is, did you change anything on the 318 flywheel such as the teeth. just want be sure all have to do is drill the 3 holes to spec and install. Thanks shawn
 
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