46 Knuckle engine

[Steve Little]

In the past I have read that people who made Knuckle-Pan motors had to do some kind of change with lifter blocks or cams but I never fully understood the process.
As per Robbie's description, the following picture shows the difference between Knuckle and Pan cam lobe placement on the spindle.
For a more definitive description I tried to set up the cases and cam cover, and take some pictures with the different cams fitted and the contact of the roller on the cam with one lifter block fitted. But I have already fitted and reamed new bushes to the case and cover.
I decided to use the original Knuckle cam and I cleaned the end spindles with my Sutton external reamer and cut the bushes accordingly.
The H cam that I pictured is also NOS, so it is a couple of thou larger than the cleaned up Knuckle cam, and wont fit in the bushes.

Rooster. Thanks for contributing. I downgraded your term “Polluting” to “interesting side note”

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[Steve Little]

Apologies Rooster. I hit "Post" before thanking you for your sentiment.
Had the neighbor not walked in at that second, it would have been a very different time.
Thanks again.

[Rooster]

I appreciate your effort looking into the cam lobe alignment issue, Steve. I confess that viewing your photo on my phone is futile, so I'll study it closely on my big computer screen the next time I fire it up.
You may find it crazy that I've saved the parts from when my pan/knuck motor was overhauled in 1975, and after all these years, I'm pretty sure I still have the original cam that shows the wear from the tappet roller running off center. I'll have to go a-digging, but I want to see it again now.
(Again, I apologize for this "interesting side note" detracting from your motor overhaul thread. But you really don't see many pan/knuck motors around. (Or is it 'knuck/pan' since it has a knuck lower end?) Frankly, unless you look at the VIN, there's nothing unusual-looking about it.)

[Steve Little]

Hi Rooster.
I don't think your phone is the problem, but more that my picture of the cams doesn't give a great pictorial reference on the subject.
I remembered another set of Knuckle cases, so I got them out and mocked up a Pan head cam and then a Knuckle cam.

First 2 pictures are a Pan head cam viewed through front lifter block hole. The close up shows the roller contact on the lobes.

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Next 2 pictures are Pan head cam viewed through rear lifter block hole.

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Last picture is a Knuckle head cam fitted

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[Rooster]

You can sure see the difference- even on my little phone screen.
Panhead cam + panhead lifter blocks + knucklehead cases = imperfect alignment (on all lobes?)
Logic would suggest that concentric loading on the roller axles might promote premature failure of roller needles. *However* - I have many tens of thousands of miles on my '41 pan, without issue.
That's very interesting stuff, Steve, and thanks for the excellent photos, and taking the time to mock up the parts. I'll go digging for my old cam later today.
There is one other modification worth mentioning about this hybrid motor: top end oiling. Since knucklehead cases lack the provision for internal oiling to the top end through the cylinders, the panhead cylinders must be drilled into the oil passageway and tapped for a fitting. Then a special "T" oil line fabricated. The 'old guy' I bought this bike from in 1974 (R.I.P. Ivan) put the motor together, and being a certified union pipefitter, fabricated a tidy little oil line out of stainless steel tubing.
Tom

[Steve Little]

Hi Tom.
For the sake of a thorough evaluation, I tried to test your following enquirey :
Pan head cam + pan head lifter blocks + knuckle head cases = imperfect alignment (on all lobes?)

Our “interesting side note” just swerved into a “We should have stuck to the main road” kind of thread.
I got out a set of aluminium Pan lifter blocks and tried to fit them in the case.
Ivan must have been handy guy with machines and tools because there's a whole mess of work and modification to be done before the Pan lifter blocks can be fitted and bolted down.
At a quick glance. Both Knuckle oil vacuum holes need to be plugged as they are outside the gasket flange of the Pan lifter blocks.
Front and rear lifter blocks need holes drilled, tapped, egged to one side.
The allure of dem alloy heads must have been too much for some of the old hot rodders.
The lifter rollers all had about 1/16" hanging off the lobes toward the cam cover.

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Ohhh thank god! Here's the the track back the main road.

[Rooster]

Main road it is, no looking back!

(A study of belly numbers is certainly in order....)

[Steve Little]

Keeping in form with the metaphors, I have come to a roadblock in this engine rebuild.

While I was collecting parts for this engine I mistakenly collected 2 front rocker boxes.
I cant continue with the rear head until I find a rear 41- 46 style rocker box.

If someone needs a front 1946 (F6 date code) or a front 1940 (A0 date code) rocker box I can offer a swap and I will pay all freight.

Or I am happy to buy it outright.

Pictures and descriptions of both rocker box's that I have to trade are listed in the WANTED section at the bottom of the main page of this forum.

I'm in a bind and offer apologies for the shameful prompt.

[Steve Little]

Hi. Has anyone used the aftermarket rocker box's that are listed on eBay?
Both listings are described as 1941-1947 but the pictures used on both of these eBay auctions, show the rear rocker box as a 1947 which is a one year part. It has the alloy extension for the rear exhaust rocker.
Does anyone offer the 41-46 style, and more importantly, do they fit like original?

http://www.ebay.com/itm/HARLEY-KNUCK...FXGUx7&vxp=mtr

http://www.ebay.com/itm/Replica-Knuc...JW7IYW&vxp=mtr

Yep!! You know I'm getting desperate when I'm looking at non original type parts.

[Rooster]

The seller states "File pictures used. Your parts will look different." For what it's worth.....

I may have a line on one, I've asked the question, awaiting reply. I'll let you know.

[Rooster]

Got a reply back from my friend, he only has a '40 rear rocker and a '38.
Sorry, no help here.

[Steve Little]

Thanks Tom.
I appreciate you taking the time to put the feelers out.
No more posts today. Spring has sprung, and the grass has woken up and I have to get my old Toro Groundmaster going.
I've got to fit new deck pulley and belt and even with a mower of this size (60 inch cut) it still takes a few hours to whip around 3 1/4 acres.

[41craig]

I have an extra rear rocker box that I believe has a B 6 date plate that I will trade. The threads are good and overall is in good original shape. It does need to be polished. I only state that I believe the date is B 6 is because of a small ding in the 6. Let me Know.

[41craig]

Rear rocker

Here are some pics of the rocker box. The 16 on the front was my number at the auction. It does have a light scrape on top right.000_0675.JPG000_0674.JPG000_0676.JPG000_0677.JPG000_0679.jpg

[Steve Little]

Hi Craig.
I have sent a message to PM box.
Thanks mate. I appreciate the help.
Regards Steve