Loom/Cpnduit On Copper/Steel Lines

[madmike]

When disassembling my 1961 M38A1 vent and fuel lines I noticed that loom is present on areas where clips are affixed to the line. Also the fuel tank line has a longer piece under the seat. Since there is paint present (USMC green) on the lines, it appears that loom was only in the area of the clips and not covering the entire line. However, some of the loom is frayed which indicate there was more of it at some point and the manual does not (at least I don't see it) show how much loom might have been on select lines. There are some things that are different on my A1 than what appears in the manual, which was printed earlier. For instance late vs early top bow hold down hardware.

So the question is: Might there be a standard for application of the loom only at clip points and maybe just on vent lines that attach to the rear of the engine and/or firewall? And of course on the fuel line under the seat.

Also, some idiot (me) got aggressive with the wire brush cleaning and did not pay particular note where the paint was/was not on some lines. Doh!!!

[wesk]

The answers to your questions lat right in your M38A1 parts manual ORD 9 SNL G-758. If you do not yet have a copy of this very important and very helpful manual you can download on our downloads page for free in a PDF file or buy one at Portrayal Press.

The lines that are required to have the loom on them are listed that way and the lengths of the loom used are on each line are given there. The exact position on each tube can easily be determined by viewing the installation and determining which areas of each tube are exposed to the most hazards such as impact from road debris or chaffing.

The illustrations below have highlighted areas that are shown blacked out. I did not high light them for this issue.

[madmike]

Thanks for the reference and I do have a manual, which helps in many cases but in this one, there are multiple references to what is called loom, or conduit, and at one place "loom, auto, asphalt finish, 5/16 ID, 1 1/4 LG, rear line". The manual writers I guess could not settle in on one term. I do note that the line lengths are different and since I have my lines intact, but without all the loom, I can now determine how much of the loom is needed on each line. But, the manual only says lg or sm loom without giving a size. So I will research that and try to find the right stuff.

For Wes, and all the folks that know this manual like a bible, it may be easy to find this stuff but for non-professional, back yard mechanics types like me, I just have a heck of a time trying to figure which one of those numbers is mine. So please bear with me until I become "enlightened".

Working it out slowly here in Mariposa, Ca. Good Lord, will it ever quit raining?

Mike

[RimfireJim]

Thanks for the reference and I do have a manual, which helps in many cases but in this one, there are multiple references to what is called loom, or conduit, and at one place "loom, auto, asphalt finish, 5/16 ID, 1 1/4 LG, rear line". The manual writers I guess could not settle in on one term. I do note that the line lengths are different and since I have my lines intact, but without all the loom, I can now determine how much of the loom is needed on each line. But, the manual only says lg or sm loom without giving a size. So I will research that and try to find the right stuff.

At least the manual for the A1 lists the individual parts in the line assemblies (like loom); the M38 ORD 9 lists just the assembly.

For Wes, and all the folks that know this manual like a bible, it may be easy to find this stuff but for non-professional, back yard mechanics types like me, I just have a heck of a time trying to figure which one of those numbers is mine. So please bear with me until I become "enlightened".

There is definitely a technique to using the ORD 9. As an engineer, I'm used to reading assembly documents and bills of material, but each one is a little different and it took me a little while to figure out the military method. My technique is:
1. Look in the table of contents to find the page number for the system
2. Look at the figure(s) that show the parts at the beginning of the system section. Note the figure number and item designator, e.g. "K".
3. If the legend is in the same figure as the drawing, find the part name and ordnance part number for "K". If not, the following page should have the legend for the figure with that information.
4. On the pages following the figure, find the subsystem of interest, e.g. "LINES AND FITTINGS"
5. Scan down the page in that subsystem looking for either the part name or the ordnance number or both. Use the illustration number in the left column to confirm, or to help find the part.
6. Yer done. Related components that are part of an assembly or that are used to attach the main part will be listed immediately below the main part.

Working it out slowly here in Mariposa, Ca. Good Lord, will it ever quit raining?

Mike

Maybe! Got an inch and a half here Sunday night, then some more yesterday evening, and the forecast is for more tonight, Friday and Saturday. Kind of puts a damper on the outside project.
Jim

[wesk]

Jim,

That's just about the way to do it. A word of caution though. Unlike some better quality manuals the attaching parts in these two ORD 9's are not always listed immediately below the higher assembly. Often they will be listed alphabetically just like their higher assembly.

In some chapters like the drive axle chapters some of the illustrated parts are actually found in a different chapter/group. IE for the rear axle which is in group 11 the figure 11-4 lists all the referenced parts in the illustration but many of them are not found in the group 11 parts listings but are in group 12 or 13 instead.

Another note is to look carefully at the illustrations. When they list reference or call out letters from the illustration and a part number they also make an annotation as to which chapter they are listed in. This annotation may be next to the part number or group of part numbers or it may be elsewhere on the reference part of the page.

I have been using military manuals since 1966. I was active duty from 66 thru 89. The worse parts manuals I have ever had to use are the old 1930 thru 1957 Pratt & Whitney radial engine manuals. They show the Pratt part number in the drawing itself then you must find that number in following page listings which are in system or assembly order instead of numerical order. Real PITA.

Mike,
The loom size would be the ID of loom and that should match the OD of the tube. I think you are confusing abbreviations. lg = length and S = steel. Go to the front of the ORD 9 (pages 5, 6 & 7) and you will find two separate abbreviation listings. One is for the many used in the parts descriptions and one for the list of parts vendors. Take for example page 94 the fuel tank to the elbow line assembly WO (Willys) Part Number 806158. It uses two pieces of loom (6 1/2 Inches Long & 17 1/2 inches long) BY (Bundy Tubing Supply) part number 3150-5. Notice the lines beginning with loom are indented below the "Line, fuel tank to elbow assy" entry. This means the looms are part of the line assy. Now look on page 95. Where you see the words Loom twice one above the other they are at the full left of the column and are not being listed as a part of any assembly but instead they are listed in their own name as the main item.
The first one lists a WO (Willys) part number 906062 and is described by length, ID, material and useage location.. In the quantity column they show 1. This is a type of asphalt impregnated loom and is not the same material as the other listed looms. The second Loom listing is the same BY part number of the earlier Looms and shows that it is non-metallic, and should be 7 1/4" long and is 0.06" thick. In the quantity column it shows the rail road track sign which means "As Required" or "As Needed" and the unit of issue is by the foot. This is listed so you can order more of the Loom in a case where you are having wear issues other then at original loom locations. So the loom you are looking for is the woven heavy fabric type for all but the one piece of asphalt impregnated type use in one place on the aft fuel line.

[madmike]

Thank you Wes and Rimfire. This really explains a lot and now begins to make sense in this gourd of mine also referred to as a head/brain combination. I need to stop looking for the quick answer in the manual and go to all the reference material to sort it out. Learning the abbreviations is essential to this and I will begin now to study/look at this manual in a different manner. I am also making a copy of this post for a study guide. Probably ought to be the first thing a novice learns when he gets on this site.

Rimfire...3 1/2 inches last night and another storm coming. I think I floated into a new zip code. May need a boat soon. Thousands of folks up here been out of power since Sat night. So I don't have it as bad as them. Yosemite just opened back up for day use but no power yet. Makes one appreciate the small things.

Mike