vivivivivibration

-
Just researching here right now, trying to find a look at the back side of a neutral balance early 318/340 flywheel. Found a picture but thinking this one is exacatlly what you have with the one drill hole in it. Got to keep looking to find a factory original 318 steel crank flywheel. Will get back when I can find a reliable picture and not someone just trying to sell something that they don't know. This flywheel has a casting number of 2264598 and is a mopar part, not sure the year though. May you can look up on the engine side of your flywheel and read the cast number, or at least the last 3 digits.

340 Flywheel.jpg



Also that helicoil hole you are talking about, yes that can be part of the problem or the whole problem. They took a 5/16" threaded hole drilled it out all the way through to next size to accept the short length helicoil. They also removed more material cutting all the thread all the way through too. Supspicous of the problem here. Also am interested of where this repaired bolt hole is in relationship to the large single drilled balance hole?

That is another good spot to use your longer test bolt with the 4 stacked up washer on to help offset the material they removed. Again make sure you have clearance and see if this helps or hurts your vibration problems. It is either going to get better or get worse. The answer will help us solve this issue. Thanks
 
OK Great that is the exact same flywheel as the picture I just uploaded on page 26

Let me research out this part number and see what year 340s they are for.
 
I would check it without the pressure plate installed, could be a bad one......may not have been balanced correctly or weights may have got knocked off.
 
OK found another pic of a 2264598 flywheel. The one drill hole.
This ad says it is for a cast crank:

340 Cast Crank Flywheel.jpg
130 tooth 318/360 castcrank flywheel p/n 2264598 located in tulsa ok.

May be on to something here. Could be you have the wrong flywheel, going to keep looking for more verification.
 
j.d.duggan said:
nm9 why the compression test?just for good practice,or what?
Click to expand...
Do the compression test just to make sure that the engine has good and even compression on all cylinders, particularly since you worke don a cylinder and it smoked so much for a while. If you have a weak/very weak cylinder, it's gonna make things vibrate just from uneven running.
 
j.d.duggan said:
So the flywheel in figure 5-21 is the wrong flywheel for my app.?Is the correct flywheel the same with no hole?
Click to expand...
Yes.

To be certain, your'e gonna have to remove the flywheel and compare it to the illustration in post number 21. If the hole in question is in the same exact place relative to the crank bolt pattern, and is the size and depth as in that illustration, then indeed it is for a later cast crank.

But, I'll say it once more.... if you don't verify that the crank is cast or forged, you will be chasing your tail.

And again, please let us know what pistons are in there. Many non-stock pistons will not be balanced to the stock crank, cast or forged.
 
OK this is what I am trying to verify that your flywheel is indeed for a cast external balance crank.
The particular casting number is just a cast number and looks like they used these blanks and machined them to what ever application they needed internal or external balance, small block or big block. So we can't go by the cast number to identify the application.

Need to go by the one Large Drill hole for Identification.

nm9stheham is stating that if it has the one Large Drill Hole like in the diagram then it is indeed for an external balance cast 340 crank. That would make the one in your car wrong for your application. Still trying to find a photo of a neural balance flywheel without the one Large Drill Hole for balance.


The casting number is just that, a casting number and it would be on all flywheels no matter what engine it bolted to.
 
There are people who have run the wrong flywheel on the steel internal cranks and they say they will start up and run ok, but when they get up around 2,000 rpm it shakes to beat heck.

j.d.duggan can you elaborate on where the worst of your vibration problem is coming in at on the rpm range. At Start Up? 2000 rpm, 3500rpm? Under Load? No Load? After warm up, Cold starts?
 
Mopar Machined lots of different flywheels for lots of different applications. Number 15 in this photo looks like the one you need for your Neurtal Balance application. No balance holes in the back side, just holes that the pressure plate bolts up with.

Might just be best to go to Summit Racing and tell them you need a brand new aftermarket Neurtal Balance stock replacement flywheel for your early steel crank internal balance 340.


Many Flywheels.jpg
 
Here is a Brand New Flywheel on ebay, item number: 253523020313

Flywheel 10.5 " 130t Internal Balance 318 340 383 440 Mopar

Brand new stock replacement ductile iron flywheel for Chrysler Dodge Plymouth Mopar 4-speed internally / neutral balanced V-8 engines with 6-bolt crank flange , 130 tooth, for 10 1/2" clutch

110.00 + 20 ship, great seller rating


340 Neutral Balance.jpg


Check to see that this 10.5" flywheel with fit up to your clutch and bell housing.
For 10.5" clutch, looks like a 130 tooth.
 
the pistons are trw L2316 I believe.only time I've noticed the vibration is at idle.that being said,I did the break-in on Tuesday,fixed some small water leaks,installed thermostat,set timing,drove the car down the street and back,mayby 8 blocks.just to see what else may need attention,brakes,steering,clutch adjustment,how it would shift.you know,just feeling her out.So I really don't know much about how she will run out on the highway at 70 MPH,or if the vibration will be there at high rev.situation
P1212835.JPG
:steering:
 
OK j.d. we have given that whole crankshaft situation a pretty good rundown. If it is the wrong flywheel I believe it would be shaking a lot worse than what your are talking about. To get a nice smooth running car everything has to be dialed in and working together.

I like your new pistons and cylinders, looks like you are doing a nice job.

A nice running engine depends on everything being all dialed and working properly. Like some of the other guys on here have been saying, start with a compression test, that is the foundation of a good running engine. 8 spark plugs out, throttle slightly open so it gets air, coil wire disconnected. Giver her a test, let us know the numbers you came up with for each cylinder. It should be at least 125 psi on a fresh build, depending on the heads you have and the compression ratio. You may have a little lower compression in the one hole where you were cleaning up the rust in the bore. Stock cast iron heads or aluminum aftermarkets. Hydraulic lifters and stock valve train ?
 
Did you build it with a new cam shaft or is it the 340 came that came with the engine ? Use the same lifters on the original cam or new lifters ?
 
one thing is obviously different between my flywheel and the one in post 21,my FW has the hole drilled all the way thru.Can anyone tell me the orientation of the hole with the dampener.To be clear,if the FW is drilled at a certain degree off the offset bolt holes in the crank,then it should be lined up with a certain degree on balancer.If I had this info I would not need to remove FW to determine the hole orientation.I could simply set the balancer to the proper degree to coincide with the hole.i.e. if the flywheel hole is at 6:00 the balancer is at 84* atdc,for example.do you see where I,m going with this example? :soapbox:
 
OK your flywheel will only bolt on in one position so that is set. The front dampers can ware out and the timing mark slot moves to a different position around the crank, the rubber in it can go bad after 50 years. Can check by having someone put their thumb on number 1 spark plug and start rolling it up to Top Dead Center, you should feel the compression stop building at this point, see if the damper is lined up to TDC with the timing cover marks. If they are not anywhere near the damper outter ring may have moved and needs to be replace with a new damper. Rock auto has them, ebay too. If this is way off then the ignition timing will be way off too.
 
You are talking about the large drill hole on the flywheel is drilled all the way through. Don't believe that is correct by the chart on #21. Chart says it's like a 1/2 inch hole and a little more than 3/4 inch deep, not all the way through. So yeah a definite concern.

Lets get a run down on the rest of the engine, step by step and make sure things are good there before we go back to the flywheel. You may need to put a clutch in it some time and that's a good time to do the flywheel then.
 
Got the short block from a guy that I know.It was built years ago for a dodge dealership owner,he never used it and ended up trading it my buddy for some work on one of his mopars.I believe it is a stock camshaft.I put in new hyd. lifters,360 j heads,188-160 valves,stock valve train,oil pressure is running around 70 PSI at 2000 R's.stealth intake,650 double pumper holley,Long tube headers,with 3" all the way out.when I get some time,mayby next week I'll try to get the comp.test done and give you some numbers.THANKS for all your input,really helps.

P2152877.JPG


P2082875.JPG


P2152879.JPG
 
balancer will only go on in one position,if not worn out,spun,then it has to be lined up in a certain position with the flywheel,correct?I believe mine is in good shape,mainly because I set the timing for start up off that balancer at 10* BTDC.Engine fired in one turn.tells me the balancer has to be good.IMHO:drama:
 
OK that all sounds and looks real good. Like the stock layout, keeps it simple . . ma mopar built them right. Love the Stock 340 cam, good performance, good idle, good get up and go, under the 500 mark on the lift so no issues there either.

You never mention what the car is, Guessing A Body Dart / Duster ?
 
j.d.duggan said:
one thing is obviously different between my flywheel and the one in post 21,my FW has the hole drilled all the way thru.Can anyone tell me the orientation of the hole with the dampener.To be clear,if the FW is drilled at a certain degree off the offset bolt holes in the crank,then it should be lined up with a certain degree on balancer.If I had this info I would not need to remove FW to determine the hole orientation.I could simply set the balancer to the proper degree to coincide with the hole.i.e. if the flywheel hole is at 6:00 the balancer is at 84* atdc,for example.do you see where I,m going with this example? :soapbox:
Click to expand...
No, there is absolutely no relationship whatsoever, so get that out of your mind LOL. Holes in the damper are not what are used to create the damper imbalance for the cast crank. The elliptic shaped ring on the front of the cast crank damper is what does that. Any other holes on the damper are to bring the final damper assembly to proper balance if neutral balanced, or to the proper imbalance if for the cast crank. Any balancing holes in the damper can be at ANY angle around the damper.

I realize you are trying to minimize work and disassembly here. But I know of no shortcut to be 100% sure on the flywheel. And this is the type of problem that if you guess, you end up fooling yourself at least half the time. The same applies to the crank; it was not clear to me from earlier posts what crank came out and went in.

j.d.duggan said:
Got the short block from a guy that I know.It was built years ago for a dodge dealership owner,he never used it and ended up trading it my buddy for some work on one of his mopars.
Click to expand...
This says that what is inside the engine is unknown and can be anything, early or late. Did you perchance take pix of the piston tops in the short block before the heads went on? Or did you notice how many eyebrows the pistons had?
 
j.d.duggan said:
balancer will only go on in one position,if not worn out,spun,then it has to be lined up in a certain position with the flywheel,correct?I believe mine is in good shape,mainly because I set the timing for start up off that balancer at 10* BTDC.Engine fired in one turn.tells me the balancer has to be good.IMHO:drama:
Click to expand...
That says the damper alignment is reasonably close...so that is acceptable IMHO at this point. Eventually, you would like to find the exact 0 mark, 'cuz it could still be 10 degrees off and fire up like that.
 
nm9stheham have been watching all of your replies on helping to diagnose what is going on here, all good stuff ! There is a picture of his new TRW L2316 piston tops on page #38 you are asking about.

We have pretty much gone through all the crankshaft/balance possibilities for now. Going over the engine build with him to see if we can come up with something out of whack. Looks like a good simple stock 71 340 engine build, cast J heads, 340 cam. So far so good looks like he is doing a good job and properly so far. We are going back to square one and have him do a compression test like you were saying and start working back out from there to see if we can help him get it to run smoother. Thank You

50 year old car build here, it's got one solid engine mount on the driver's side, the other is rubber and any little miss in the engine could send that up through the frame and body to exaggerate it.

Will keep digging as we get time . . .
 
You must log in or register to reply here.
-

Back
Top