Fly wheels

[Northman]

When I did a quick check on my bottom end I didn't notice that I have one steel washer on one side of the wheels and a bronze on the other. Sooooo I thought the end/side play was nice. Turns out the steel washer was stuck to the rod giving the illusion of correct space at a glance.(today I wanted to measure to be certain and discovered it) The fact that it spun its self out of the fly wheel is one thing, the other is the amount of open space for the rods. I realize they center themselves. The shake at the wrist pin end is still under 3/32. Ayone ever encountered this? I've done a couple bottom ends in the past (and its been years) and never ran into too much space, its always been hoping for enough room after tightening the nuts.
Another mystery is what I found in the breather. Nothing from this set of rings but it does look like oil ring pieces from sometime ago. I had to actually pick them free from the gear end (inside). Gear and breather hole are fine.

I can't help thinking that I'll find more issues. If I don't thats fine. At this point I'm thinking just do the bottom end for a complete job and not worry about it.
Any thoughts?

Northman

[1964FLDUO]

I found myself in a similar scenario about a month ago, to make a long story short, someone worked on my motor and did a half ass job. I just decided to rebuild the whole motor instead of having more problems arise later. When in doubt check everything.

[1950Panhead]

23973-41 is the rod thrust washer, made of steel.
Originally staked in four places around the perimeter.
I have seen wear from rubbing on the rod.
I had a WL where someone removed the washer to get clearance for the rod, had to replace flywheels.
Jerry

[58flh]

1964flduo-----SAID IT RIGHT!----If it was mine I would split the cases & see what im dealing with, instead of wondering!& that 3/32s at the wristpins!---Is a definite do-over! ,Save yourself the problems down the road,& rebuild it yourself! You obviously have done bottomends before---GO for it!, Then YOU know what time it is!.----Richie

[RUBONE]

If the thrust washer has come loose in the flywheel a full tear down is in order. Period! The thrust washers are critical to preventing the rods destroying the flywheels. If one is bronze it has been replaced in the past with a late style replacement part. Excessive side play between the flywheels is not good, nor is too little. Sometimes the rods even need to be replaced if they are worn excessively. The overall width needs to be wider than the assembled bearing cages and still have some clearance. If the washers have spun in the flywheel for any amount of time the pocket they sit in is usually bad. Oversize washers are available. The rods only "center" themselves in a perfect set of conditions. If the rod has any twist or tweak, if the bore is not perfectly concentric, if the piston has any issues, all those will cause the rods to thrust to one side or the other. If the flywheels are not centered and spaced correctly they can also cause rubbing on one side or the other.
Just remember, "Fix it right, fix it once"
Robbie

[Northman]

Agreed. Thanks for the input and elaboration.

Northman

[Cotten]

...Sometimes the rods even need to be replaced if they are worn excessively... Robbie

Robbie!

In total agreement with everything you mention, I would add that often fresh races alone can restore the original width of the bearing surface of rods.

....Cotten

[Northman]

Anyone ever have a rod race spin free or seen one that has?
Northman

[RUBONE]

I have seen several rod races spin, always the female rod, usually only one side. I have seen bearings welded to the races from heat, rods welded to thrust washers, rollers that skidded instead of rolling, alloy cages that melted like solder, you name it! It requires replacement of the rods though as repair of such an issue is not practical and invariably the big end eye is elongated or egg shaped to a large degree. If that is going on in your engine it is time for a new set, and careful inspection to determine why along with very careful assembly of the new components to assure correct free play, centering, and oil supply!
Good luck and keep us posted on progress.
Robbie

[Northman]

Robbie, No nothing of the sorts going on here....not even close. Holy crap I've never seen or heard of anything like you said.

The reason I asked is of past situations. Not wanting to give anyone a bad rap..... but I believe that certain places of business would rather sell a new set of rods rather than rebuild. Less work and still a nice profit.I speaking of just the race replacement process. They tend to scare the customer that they could have issues with new races. I have heard it with my own ears. I've put races in and have taken some extra steps that are just precautionary. Not necessary. Never had an issue. I agree with everything you said, if the shit is too tight its death and destruction. loose same deal. 3 hole crank pin is only good if theres oil. I like to stay towards the bottom of tollerences but not at the minimum. How its treated for the begining miles is important too. I did a stroker rebuild for a guy many years back and I wouldn't let him have the bike untill I had a couple hundred on it.(over kill) As you know if somethings going to happen its usualy soon. Anyway I posted the question so all could gain knowledge and I like to hear theroys and opinions. I commend you and others for your honesty and wisdom. I've never come across a site like this where its straight up and trustworthy.....with some humor too. I'll be splitting my wheels this weekend, thanks to a Brother that I sold my tools to that is always willing to let me use them. A Brother in need is a Brother in deed!

Northman

[Cotten]

Just an opinion,

A rebuilt OEM rod set is better than aftermarket;
Even if not from the same motor, they will approximate the original balancing as closely as needed.
Performance rods are very heavy, and overkill for a vintage machine, even if stroked, and demand an expensive re-balancing that otherwise would be un-necessary.

Ultimately, used rods are already stretched, and can be safely fit tighter at the crank, giving longevity an advantage.

The caveats are obvious: The quality of a rebuilt set of rods not only includes precision machining and quality materials, it also includes magnafluxing, shotpeening, demagnetizing, and final straightening and alignment.

New rods are far cheaper, but you get what you pay for.

....Cotten

[RUBONE]

New rods are far cheaper, but you get what you pay for.

Amen to that Cotten!
And Northman,
you are on the right track, stay the course and you will be fine!
Robbie

[FlatHeadSix]

If the thrust washer has come loose in the flywheel a full tear down is in order. Period! The thrust washers are critical to preventing the rods destroying the flywheels. Robbie

yep! Here's what happened to my '31 VL crank when the thrust washer came loose, it destoyed the flywheel. And, there is no going back, once it eats into the wheel the only cure is to replace the wheel.
mike

[Northman]

Helllloooooo
Just figured I'd give an up date on the flywheel action. I split the wheels and found that the wheel is good. I got lucky. The thrust washer is barely there...like paper thin. I ordered parts and should have them this weekend. In the mean time its been cleaning and more checking. I checked the run out on the pinion and the sprocket sides of the fly wheels (rim) and found they are quite a ways out there. .013 and over .018 on the other, Hard to believe. I don't have a stand so I used my lathe. Some say its better than a stand, others don't, but I know its not an issue with the lathe.

So much for thinking the bottom end was mint as I thought at the beginning of my project post. I have always done a good inspection on stuff, I just wait till I get to that particular point in what ever process I'm moving in. This time I learned to keep my trap shut..... I'll be posting pics soon in the project area.

Northman

[Cotten]

... I checked the run out on the pinion and the sprocket sides of the fly wheels (rim) and found they are quite a ways out there. .013 and over .018 on the other, Hard to believe. I don't have a stand so I used my lathe. Some say its better than a stand, others don't, but I know its not an issue with the lathe...

Northman!

The sides of flywheels nearly always bulge in the region of the crankpin,independant of the true crank axis.
If the metal was not malleable, it would shatter under the forces of the motor.
Although this is a much older example, it was actually a less malleable material than later H-D wheels:

FLYBULGE.jpg

Each main shaft should be trued independently to the undistorted portion of the "rim" of its wheel, after lapping of the tapers not only for inspection, but often for correction as well.

Centers are centers, whether in a lathe or an inspection stand.
A lathe is only more practical in terms of double-duty floorspace, or if management leaves you no choice but to beat upon the assembly, as its parts are more economically replaced when damaged.

...Cotten