The first "Hawk-Rod" resurrection, Roadkill style

[HawkRod]

OMG. I MAY just have found the source of the vibration: As several of you suspected, an axle.

Hard to see in this picture, as I can't hold axle, straight edge, feelers and camera with only two hands, but there is about .010" bend in my passenger (right hand) side axle.

It is probably very hard to straighten this, so I guess I am looking for an emergency right axle replacement.

I am hopeful thought that I found the source of the problem!

 

[1 Wild R/T]

Yup - too late! Engine has been in and has about 1500 miles on it so far.

I don't remember my final end gap; it was larger than that but I can't quote you a number. Hopefully the engine will last the trip - no digging into it at this point...

I hated to even mention it, I did the same thing on my first Hypereutectic build back in the early 90's... And broke a piston, just a small chunk off the edge of the upper ring land... The engine made a weird stumble & a noise but kept running... A week later I pulled the head & found the damage... Didn't hurt anything but the piston & ring... Tore it down, one piston, new rings, quick hone, bigger ring gap & let it go... Still runs great...

Hopefully you'll be fine, if not hopefully you get lucky like I did...

 

[64fury74charger]

OMG. I MAY just have found the source of the vibration: As several of you suspected, an axle.

Hard to see in this picture, as I can't hold axle, straight edge, feelers and camera with only two hands, but there is about .010" bend in my passenger (right hand) side axle.
View attachment 1270983

It is probably very hard to straighten this, so I guess I am looking for an emergency right axle replacement.

I am hopeful thought that I found the source of the problem!

Told you that you were going to find the potential source and that it was just a matter of checking everything off on the list and eliminating each step of the way. That is looking like the culprit and wouldn’t likely be noticed just rolling on the deck.

 

[JDmac72chrgr]

Persistence paid off, WAY TO GO HAWK!! .010", little sum-bitch!!!

 

[Nxcoupe]

OMG. I MAY just have found the source of the vibration: As several of you suspected, an axle.

Hard to see in this picture, as I can't hold axle, straight edge, feelers and camera with only two hands, but there is about .010" bend in my passenger (right hand) side axle.
View attachment 1270983

It is probably very hard to straighten this, so I guess I am looking for an emergency right axle replacement.

I am hopeful thought that I found the source of the problem!

Did you check both? And if you turn it 180* does the straight edge wobble with it being high in that spot?

 

[zyzzyx]

The axle should have a center on the inboard face. You can stick it in a lathe and check it out.
You can put it in a press and straighten it if it's only 0.010!

 

[HawkRod]

Persistence paid off, WAY TO GO HAWK!! .010", little sum-bitch!!!

Damn straight it's a little "sum-bitch". This thing has been fighting me for years!!!

Did you check both? And if you turn it 180* does the straight edge wobble with it being high in that spot?

I checked both axles.
The one that is bent with a .010" drop in the center makes the straight edge wobble in the center when I turn it 180*. I won't exactly swear to .010", as it might be .009 - .012", but it is pretty definitive.
I was not able to measure any low or high spot on the other axle using the same method of measurement.
Disclaimer: I used a pretty rudimentary way to measure straightness. I simple laid my machinist straight edge on a straight part of the axle (it tapers down in two spots towards the splines), and looked for light or tried to feel a wobble.

The axel should have a center on the inboard face. You can stick it in a lathe and check it out.
You can put it in a press and straighten it if it's only 0.010!

I might certainly try to do that. First, getting another axle quickly will likely not be easy. Second, if I get another axle, then I also need to (most likely) put new bearings into the axle, and that is yet another job to do.
If I can straighten the bad axle out that would be great. The only issue is that I'm not sure I have a very controlled method of bending it back.

 

[zyzzyx]

Take runouts and mark the high spot every two inches. Use a piece of copper if you can
under the axle ends. Find the high spot and put an indicator on it close to where you are
pressing. Try moving it 0.060 on the first try and go up from there in 0.060 increments.
It will spring back every time until you get it to start to yield. Once you get it to start
moving, go slow.

 

[64fury74charger]

Damn straight it's a little "sum-bitch". This thing has been fighting me for years!!!


I checked both axles.
The one that is bent with a .010" drop in the center makes the straight edge wobble in the center when I turn it 180*. I won't exactly swear to .010", as it might be .009 - .012", but it is pretty definitive.
I was not able to measure any low or high spot on the other axle using the same method of measurement.
Disclaimer: I used a pretty rudimentary way to measure straightness. I simple laid my machinist straight edge on a straight part of the axle (it tapers down in two spots towards the splines), and looked for light or tried to feel a wobble.


I might certainly try to do that. First, getting another axle quickly will likely not be easy. Second, if I get another axle, then I also need to (most likely) put new bearings into the axle, and that is yet another job to do.
If I can straighten the bad axle out that would be great. The only issue is that I'm not sure I have a very controlled method of bending it back.

Amazing how much trouble one little wrinkle can create. Hopefully you will get this replaced soon and laughter will ensue as you blast down the street.

 

[HawkRod]

I tried straightening the axle today. I did not manage to fix it, and then ran out of time.

Below was my jig (later "improved" to clamp the wood ends firmly to the metal saw horses). I had the axle through my 20 ton hydraulic press, supported by the ends.

I measured the center of the axle, and then rotating the axle confirmed the high and low spot. I saw about .020" difference between the high and the low. Now the needle bounced around a little bit since this is not a finely machined surface, but it was consistent. This confirmed the bend I saw with the straight edge.

So then I put the axle so the high spot was facing up and put some pressure on the axle trying to remove that bend. I managed to reduce the needle deflection to about .014", but then I saw that the splined end seemed to be moving. So I may have bent the end more while measuring the middle of the shaft (?). I ran out of time to play with it, but I feel like I need a better way to confirm that it is straight.

I may check if there are axle straightening services - I likely need to spend my time on some other things.

 

[zyzzyx]

Support the splined end a little more inboard about three inches. Remember, you can
yank it around pretty much all you want because it's only 0.010 or 0.020. The horses are
probably deflecting alot! Try and use the press beams diagonally with copper or aluminum
between the axle and supports. It is soft enough to support but not damage. If you don't
feel confident enough, take it to a machine shop to straighten. Remember, NO HEAT!!!!

 

[HawkRod]

Support the splined end a little more inboard about three inches. Remember, you can
yank it around pretty much all you want because it's only 0.010 or 0.020. The horses are
probably deflecting alot! Try and use the press beams diagonally with copper or aluminum
between the axle and supports. It is soft enough to support but not damage. If you don't
feel confident enough, take it to a machine shop to straighten. Remember, NO HEAT!!!!

So I tried some different ways to bend the axle back, including putting it diagonally across the press. No luck.

I bailed out and called Dr. Diff and ordered two new axles. Then I know they will be straight. I know I am chickening out and throwing money at this when I should be still working to fix the axle, but I am out of time. I need to get this thing back together - May 2nd is right around the corner...

 

[qkcuda]

Did you go with green bearings or tapered, Hawk?

 

[JDmac72chrgr]

@HawkRod
Fact or Fiction:
Straighten axle & get it together, the bent axle & vibration WOULD be on your mind the whole vaca/trip THEREBY taking away from ENJOYING the trip.
Didn't chicken out, so ENJOY THE TRIP!! Oh, KEEP US POSTED with pics & videos of the journey

 

[zyzzyx]

Time waits for no one! I get it. Been there. GOD, I hope this fixes it!

 

[oldbee]

Guarantee it’ll be a good trip. Ur starting the day after my birthday!!!!

 

[zyzzyx]

Yeah, I'm glad the 18th of April is over! Taxes are done and now I can sleep at night.
Damned, I hate those No-knock warrants in the middle of the night!

 

[HawkRod]

Did you go with green bearings or tapered, Hawk?

Green. Tapered would have taken longer, and I didn't have the time. Green will work fine for what I'm doing!

@HawkRod
Fact or Fiction:
Straighten axle & get it together, the bent axle & vibration WOULD be on your mind the whole vaca/trip THEREBY taking away from ENJOYING the trip.
Didn't chicken out, so ENJOY THE TRIP!! Oh, KEEP US POSTED with pics & videos of the journey

True. I need to get this pig done.
There will be lots of pictures, for sure. My other thread has been neglected for awhile, but soon it'll get lots of updates (I hope)!

Time waits for no one! I get it. Been there. GOD, I hope this fixes it!

You're telling me!

 

[qkcuda]

I had green bearings in the cuda and they worked fine. Just make sure that they seat completely, sometimes the new axles are a tad long and the thrust button in the diff causes problems.

 

[HawkRod]

Looks like my axles will not be here until Tuesday next week.

In the mean time, I welded up the transmission tunnel. To keep it from warping, I welded it with tons of little spot welds. It looks like crap, but it is solid, and I used a light to find any small holes that hadn't been fully welded.

Some time in the future I will grind it smooth and make it look nice, but (1) it is under the carpet and console so it won't be seen, and (2) below is what my car looks like only a few days before we are scheduled to leave.

Notice the bright light in the upper right. Just like on the driver's side, I found rust on the passenger side in the wheel well. I went after it to get rid of all the rust, but that has left me a gaping hole. Time to get out the welder and start welding pieces of metal back in to repair it.

Sigh. This car really IS a RoadKill....