1966 Shovel engine rebuild

[Steve Little]

Hi Dave.
Good to see you contributing.

When I was a first year apprentice I was given a job to tack and weld up. Got to the end of the job and it was twisted. So I wholleped on it a few times with a big hammer and got it straight.
The foreman came over to check the job. He didn't yell. Just ran his finger through the 3 hammer marks.
As his finger ran over the first indent he said: Steven Little.....Second indent.....Howard st........Third indent...Ballarat

If the description is lost on you, each time I marked a job with roughness, it was like I was leaving my signature of ineptness.
I've been conscious of it ever since.

[Steve Little]

This balance kit only gets to see the light of day every few years. I only build my own engines...until now.

Product disclaimer.
The following pictures and comments are for the entertainment of the regular viewers of amca tv.
If you professional engine builders see a glaring error, or think I have neglected to add some pertinent piece of information, feel free to chip in.

My mill is a nice level place to work so lets set up there.




I take a couple of minutes to calibrate the triple beam scale each time I use it. I do this in case I have knocked the calibration screw when I put it away and it kind of gets me and the scale acquainted again.





From here, I weigh up pistons, rings, nuts, etc, etc. See sheet in next picture below.
Each weight is recorded in the sheet that comes with the S&S balance kit.






Most of the parts are easy to weigh up, but when it comes to the rods, I find it takes a bit of getting to know how to set the rod on the scale and the support

[T. Cotten]

An interesting experiment, Steve,..

Would be to hang your finished, balanced and trued crank on knife-edges, and add weight at the rod bushings until it came to balance, so you could then back-calculate to see if it agrees.

....Cotten

[Steve Little]

Hi Tom. Thanks for gettin in here with us. Can you give a bit more detail?
While your collecting your thoughts and getting it on paper, I will forge ahead with picture posting. I'm a long way in front of the pictures

This picture shows the rod support supplied in the S&S balance kit. The rectangular support works ok, but the external finish of the rods is rough and the rods rock around.




In the next picture, I have changed to a round bar which is placed inside the rod. I made this rod a couple of engines ago and found it better to weigh the big end of the rods. The machined area of the rod race is better to support the rod during weighing.
While I was using the round rod during this build I had a thought. If I turned /ground the rod down to 3/16” or 1/8” diameter, the smaller radius will have less contact on the shell and might alleviate some of the drag issues when weighing the rods. Future Steve will report on that.






When the rod is set on the scale at the right place, I gently lift the end of the beam up and down a few times. It helps to walk the rod into place and I find it gets the tension off the contact areas.

If your weighing the end of a conrod and the beam looses the free bouncy action, it will not give you a true weight. When I get the end of the rod to that nice loose spot, I hold the beam at the limit of its movement and gently let it go. It should free fall/rise and bounce to a slow stop. I do this 3 times and look for repeatability in the reading.







As you can see in the spec sheet, I got pretty close to the “Actual weight” of the rods.
If anyone has a better method of weighing the rods, can you chip in with it?

Using the S&S formula I calculated the bob weight and set it up.

[Steve Little]

The thick shim sitting on top of the bob weight is the metal that needs to be removed from the bottom area of the flywheel.






Out of curiosity I weighed the old components that came out of the engine and calculated the balance weight....put it on the bob weight and checked it......wasn't within a bulls roar. Maybe the balance job was from a previous build.

Enough of the ramblings...Don't adjust your set...back to the scheduled program.

[Steve Little]

An interesting experiment, Steve,..

Would be to hang your finished, balanced and trued crank on knife-edges, and add weight at the rod bushings until it came to balance, so you could then back-calculate to see if it agrees.

....Cotten

Hi Tom.
I apologise in advance...Today has been a day that required a lot of concentration.
I think I get what your proposing, but I don't know how we could do it?
Maybe your just proposing something that would be fun if we could.....but we cant.
Not sure, and not making fun, just gone past, me able to think.
I will post more pics tomorrow.
Regards Steve

[T. Cotten]

Well, Steve,..

First you would need some real knife-edges, tall enough to hang the crank with rods upon it.
(If I were to do it all over again, I would use 1" round rod stock instead of ground planer blades .)

My philosophy is that working with the real hardware is a lot easier, faster, and more accurate than faking it with bobweights.

....Cotten
PS: My contempt for the bob-weight approach stems from my dynamic balancing experience on a Stewart-Warner apparatus, where I found that just disassembling and reassembling a taper can change results, even though it was trued each time.

Good thing these things are forgiving, huh.

PPS: Many enormous lathes still exist that have enough "throw" to accept a crank with rods between centers, which should do as well for balancing as many of the "knife edges" I've looked at...
Its all about the patience and care of the observer.

[Steve Little]

Thanks for the info Tom.
Be an interesting thread for you to chronicle?

Both flywheels were too heavy in the counter weight area. First thing to go was the lead and then started drilling new holes and chased the imbalance for a few hours. The bright holes in the bottom of the wheels are mine. Got both wheels perfect...which means I could place them at any position with the bob weight fitted, and they would sit.






I find that when I am close to the end of a balance, it can come down to drilling a small amount of shavings out of a hole will make the difference between a slow creeping wheel, and a complete stop.
The picture below shows the amount of swarf drilled out of a hole that made the difference.

[Steve Little]

Filed the key way edges on the old sprocket shaft and all the key ways in the flywheels, and did a quick lapping of all the tapers and shafts with fine paste. I do this to see how the shafts are sitting in the tapers by looking at the witness mark.
The sprocket shaft had a hollow that came out with four or five quick turns. The taper on new Jims pinion shaft, and the S&S flywheels, needed a little more encouragement.
The crank pin only took a few turns on each end and had a nice, mat finish.
Washed all the shafts, nuts, keepers, screws and gave special attention to the oil galleys.



Sprayed all parts with Brake clean and fitted the shafts and nuts. Pulled the nuts up to 130 ft lbs and then fitted each wheel in the centers to check the run out. The pinion wheel pulled in at 003” and the the sprocket at 004” After a quick adjustment with my copper hammer and a hard wood block, the run out reduced the pinion to 000” and 001”on the sprocket. I then tightened the nuts up to 240 ft lbs and did another run out check. Pinion 001” smacked back to 000” and Sprocket shaft stayed at 004” but smacked into submission at ˝ a thou.

[Steve Little]

I've had this set of centers since 1994 and built many sets of flywheels on them.



When I finished assembling the flywheels, I took some videos of the readout on each side while they rotated, with my shop camera to show the readout but the footage is terrible and grainy. I don't think I have used this option with the camera before, but thought that it was a reasonable camera up until now. Olympus SP-500UZ
The run out on the pinion was :0001 (1 tenth of a thou) but I could not get the sprocket shaft any closer than 0:0005.
It wasn't for lack of trying. I would wedge or clamp the flywheels and a couple of times I wedged and clamped the flywheels at different points to try a different approach but could only get one side to zero, and the other side would be 001" or 002". I chased it for 6 hours and gave up with a happy medium.
Next week I will post pictures of the work I did on the cases.

[Steve Little]

After removing the cam cover I could see the inside of the cases looked darker than usual.
The dark stain had a sooty look, like burnt oil and would not move when rubbed with my finger.
The owner has a nice collection of vintage Harley's and during a discussion said this engine ran very hot compared to the others.
Since purchasing the bike, he's only done 2000 miles and I know he's on the ball with maintenance and oil changes, so this sooty look was a little puzzling.
Both these picture were taken much later in the build and they had been washed in solvent about 3 times after each procedure. The sooty stain is still evident in these pictures after multiple scrubs in solvent.

[Steve Little]

Looking at the internals of this engine, I think it was assembled just prior to the bike being purchased.
If the pictures don't tell the story...think of sitting in the back of a compact Ford, between two big meat heads on a 1/2 hour drive to the pub.
There was no end clearance set on the cam. The shim has “friction” welded to the cam, and was doing its best of trying to bore through the cam lock washer...and nearly had.
Here's some pictures of the Pinto... I mean cam.

[Steve Little]

Time for some crack repairing. In my time of repairing cases, I have seen a number with this type of cracking or even pieces missing. The witness mark which is left by the nut, resembles a countersink into the hole, instead of a spot face. The countersink converts some of the pressure of the nut outward, which then cracks or breaks the side out.
Wondering if Harley intended the nuts to bed into the soft alloy to stop them loosening up?
Colony provide washers in their kit which will stop the case cracking, if the correct tension is put on the nuts.











While I had the mill set up, I spot faced all the case bolt surfaces.

[BigLakeBob]

Nice work Steve, I always use washers whether it's right or not.

[Steve Little]

Thanks Bob.
We'll protect the cases while we are custodians, and the next generation can do what they like.
Regards Steve