Building a 42WLA Blank Boss Engine in a Crate

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17thAirborne
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Building a 42WLA Blank Boss Engine in a Crate

Post by 17thAirborne » Fri Jan 27, 2017 5:11 pm

This is the first post of my efforts to build a 42WLA blank boss engine in a replica shipping crate. I am gathering data on the crate and cases on another thread, but as I find parts and begin the assembly process, I will post progress here. It will be slow going until I get the first required parts together to start the project. Progress will be slow, so bear with me as the posts trickle in. This will be another humbling learning process for me as I step through the procedures and face the challenges of finding the correct parts.

I can already see that the flow of NOS parts is pushing me toward OEM items in some cases. Perhaps a few nice shows like Davenport or the one in N. Dallas might help, but for now the usual sources will be tapped. I want to build this with the highest percentage of NOS/OEM parts, and I will make it a functional engine, not a shell with no guts.

Once I sort out my concerns and desires regarding Type III or Type IV, i will be able to move on. For now, I plan on starting with the fly wheels, connecting rods and pistons. I have a 1942 NOS STD cylinder for the front, but my rear cylinder is OEM, .040 over and 1945. As difficult as it was to find even a single usable rear cylinder, I will have to live with the fact that the rear cylinder is incorrect for the date. I have a handful of other parts, but the quest to find what I need will be fun. I should have a nice NOS set of cases to begin with, but have some time to sort out the issue of appropriate type to build that I started here:

viewtopic.php?f=23&t=282675

I welcome comments, suggestions and direction as I begin this process.

Here is my start :shock:
Untitled-1.jpg
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Last edited by 17thAirborne on Fri Jan 27, 2017 8:10 pm, edited 1 time in total.
Oz

WLA SN 42WLA56511, USA-692406
WC-12 SN 8682327, USA W-231808

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Re: Building a 42WLA Blank Boss Engine in a Crate

Post by OLDABEWLA » Fri Jan 27, 2017 5:57 pm

Oz,

You will want to find a set of cylinders that the bores sizes are the same if they are not the same it won't be good.
☆42WLA Harley-Davidson #19,246 Type III

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Re: Building a 42WLA Blank Boss Engine in a Crate

Post by 17thAirborne » Fri Jan 27, 2017 8:07 pm

OLDABEWLA wrote:Oz,

You will want to find a set of cylinders that the bores sizes are the same if they are not the same it won't be good.

My understanding is that for the .040" over sized cylinders, 1.33CI is added to the volume of the cylinder. That amounts to 2.9% increase in volume over the standard 45.12 CI I was under the impression that this would not place significant torque or stress on the system. I am, however open to hearing why I should be careful about this. I'm always ready to learn.

Thanks
Oz

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WC-12 SN 8682327, USA W-231808

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Re: Building a 42WLA Blank Boss Engine in a Crate

Post by OLDABEWLA » Sat Jan 28, 2017 8:22 am

I believe you will have two different compression ratio in your engine.
I'm not sure if it will make a big difference? but I like them to be the same bore sizes to keep equal stress inside the engine
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Re: Building a 42WLA Blank Boss Engine in a Crate

Post by 17thAirborne » Sat Jan 28, 2017 3:18 pm

OLDABEWLA wrote:I believe you will have two different compression ratio in your engine.
I'm not sure if it will make a big difference? but I like them to be the same bore sizes to keep equal stress inside the engine

I spent all of last year looking for decent cylinders. NOS front ones are available from time to time, but to find an unmolested rear cylinder seems much harder. It will be some time before I get to the cylinder phase, so I have some time to keep looking for one with less wear.

Anyone want to trade their NOS rear cylinder for mine :lol: :lol: :lol:
Oz

WLA SN 42WLA56511, USA-692406
WC-12 SN 8682327, USA W-231808


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Re: Building a 42WLA Blank Boss Engine in a Crate

Post by OLDABEWLA » Sat Jan 28, 2017 8:54 pm

Those rear cylinders are the ones that run hotter and wear out faster than the fronts thats why they got used first up over time.
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Re: Building a 42WLA Blank Boss Engine in a Crate

Post by Lib45 » Sun Jan 29, 2017 9:51 am

Funny...I always thought so too..
My rebuilder, having rebuild 100's of engines over the years, says he's yet to see an engine having the rear cilinder worn further than the front one.
IOW; they usually wear equally fast in normal use..

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Re: Building a 42WLA Blank Boss Engine in a Crate

Post by 17thAirborne » Sun Jan 29, 2017 10:01 am

Lib45 wrote:Funny...I always thought so too..
My rebuilder, having rebuild 100's of engines over the years, says he's yet to see an engine having the rear cilinder worn further than the front one.
IOW; they usually wear equally fast in normal use..

The two I have are not from the same bike, (front one is NOW and there are still a good number of those) but I cannot determine why the ratio of front cylinders available to rear ones is so much higher. That being said, I am hoping that the difference in the two will not be problematic for normal riding.
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WC-12 SN 8682327, USA W-231808

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Re: Building a 42WLA Blank Boss Engine in a Crate

Post by 17thAirborne » Wed Feb 01, 2017 2:00 pm

Although this is far ahead of the process, i was fortunate to find these two nice jewels for a very reasonable price. There are supposed to be two in the crate. One more item off the check list.
spark plug boxes.jpg
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Oz

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WC-12 SN 8682327, USA W-231808

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Re: Building a 42WLA Blank Boss Engine in a Crate

Post by 17thAirborne » Wed Feb 01, 2017 2:52 pm

Had a little time to fiddle with the tag. This is the first effort. i need to improve the centering on the hole punch around the paper ass-holes and use rubber cement instead of craft glue. I also need to fiddle with the HD font, making slightly bolder and spread the letters out a little.

Here is a side by side comparison of my engine tag with another HD part tag.
printed tag.jpg
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Last edited by 17thAirborne on Wed Feb 01, 2017 3:08 pm, edited 1 time in total.
Oz

WLA SN 42WLA56511, USA-692406
WC-12 SN 8682327, USA W-231808

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Re: Building a 42WLA Blank Boss Engine in a Crate

Post by 17thAirborne » Wed Feb 01, 2017 3:08 pm

And here is a comparison of the origanl tag on an image and mine super imposed.Close, but needs a bit of work.

The original tag is on the one owned by GARY's BUNKER
tag comparison.jpg
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Oz

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WC-12 SN 8682327, USA W-231808

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Re: Building a 42WLA Blank Boss Engine in a Crate

Post by 17thAirborne » Wed Feb 01, 2017 3:17 pm

I finally secured the cases today, I have a nice set of fly wheels coming from Steve Lemay and a few parts on hold with Craig. I'll focus on some hardware for the flywheels and connecting rod assembly and hopefully get those together and built by the end of March.
20170126_115927.jpg
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Oz

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WC-12 SN 8682327, USA W-231808

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Re: Building a 42WLA Blank Boss Engine in a Crate

Post by 17thAirborne » Fri Feb 03, 2017 12:12 pm

Another part arrives. I won't open the wax seal until all of the other parts for the flywheels and connecting rods are available. I am amazed at how these things are packed.

This is a combination of parts 348-29 (Crank pin) and 364-37 (crank pin nut)

which becomes HD part 348-29A
crank pin with nuts.jpg
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Oz

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WC-12 SN 8682327, USA W-231808

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Re: Building a 42WLA Blank Boss Engine in a Crate

Post by 17thAirborne » Sun Feb 05, 2017 2:18 pm

While I wait for parts to roll in I decided to try and replicate the engine unpacking instruction sheet. All i had to refer to was a low resolution image of the original sheet posted on the Gary's Bunker site. When it is enlarged, the font is barely readable, so I have to try and interpret what the words were using a big fatty engine uncrating sheet provided by Craig. Some of the sentences were the same or similar and some were completely different. You can see from the images posted below that it is easy to read.

I have added an image of the finished product rendered in open office using an Underwood Typewriter font. There are a few words that I am not sure of and they are in red. If anyone has any ideas what they are please let me know.

If anyone wants an email of the document, please let me know and I'll send it out. Here are the two pages from Gary's Bunker
Spare-Motor-pkg-slip-1-of-2-230x300.png
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Spare-Motor-pkg-slip-2-of-2-230x300 (1).png
Spare-Motor-pkg-slip-2-of-2-230x300 (1).png (124.62 KiB) Viewed 1218 times
Here is my rendition still requiring a bit of clarification of a few words.
unpacking sheet 1 lr.jpg
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unpacking sheet 2.jpg
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Oz

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WC-12 SN 8682327, USA W-231808

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Re: Building a 42WLA Blank Boss Engine in a Crate

Post by 17thAirborne » Mon Feb 06, 2017 7:00 pm

WOrking on the small stuff again as I await parts. I decided to make the first prototype red engine caution tag and weather the engine un-crating instruction sheet to see how it looks. I am still awaiting input on a few words (above post), but took the liberty to see how a finished product would look. Here are the results of the first run effort.
more tags.jpg
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Oz

WLA SN 42WLA56511, USA-692406
WC-12 SN 8682327, USA W-231808

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