Vent Line Routing

ocwd · Post by **ocwd** » Wed Jul 22, 2020 11:15 am

I've looked through the TM and Ord manuals for a good illustration for some of the vent lines. I did find a bunch of good pictures and illustrations but still missing some pieces. From the image below, I would like to install N & R before I put my tub back on. I haven't found any good pictures or illustrations doing a Google search or searching here and on G503. Does anyone have a good picture of these two lines installed with the tub off? Looks like the same question is asked over and over here and on G503.

4x4M38 · Post by **4x4M38** » Wed Jul 22, 2020 3:45 pm

Hi,
Do you already have O and Q installed with the fittings? With the correct lines they should only go one way.

Unless you are making your own. In which case the previous lines and fittings being installed should make creating and installing these two pretty easy.

Do you have Ryan's Reference Book?

Take a look at the bottom photo on page 21, top photo on page 172.

Take care,
Brian

rgmutchler · Post by **rgmutchler** » Wed Jul 22, 2020 4:08 pm

Ryan's green M38 book has some good diagrams and lists of the different fittings and tubing. There are some typo mistakes in regard to tubing size but it is easy to sort out.

Ryan's book is great for figuring out some of the different systems and parts for these jeeps.

ocwd · Post by **ocwd** » Wed Jul 22, 2020 4:22 pm

I'll take a look at the Green book when I get home tonight. I've only installed M (carb to cross over tube) so far since it's one of the easy lines. I figured that I would do O & Q once the tub is installed since the tub and air cleaner aren't installed yet.

Thank you,

Dave

ocwd · Post by **ocwd** » Thu Jul 23, 2020 7:03 am

It looks like I can run these lines after I put the tub on. Line R routes to the frame then back to the dash. Still not sure about line N. N (master cylendar to air cleaner) looks like it's fixed to the engine block along with line S (gas tank to air cleaner).

It's starting to get clearer. Where does R take a turn to the dash? Is the dash Tee fixed to the actual dash or the fire wall near the air cleaner?

Kendall · Post by **Kendall** » Thu Jul 23, 2020 7:29 am

Here is the vent line from my transfer case. Hope this helps.
Kendall

ocwd · Post by **ocwd** » Thu Jul 23, 2020 8:41 am

Thanks Kendall. Looks like you have a late set-up. Mine will be early. I found an illustration in TM 9-1804A showing the Transfer vent line routing on the passenger side of the shift canes. Also, the lube chart in the M38 reference book shows it to the right of the canes. The diagrams I've seen for the later set-up are like yours.

Post by **wesk** » Thu Jul 23, 2020 10:20 am

All you folks with the early. M38’s should be using TM 9-804. That’s theSep 1950 predecessor of TM 9-8012. The illustrations in that manual will have you drooling!

ocwd · Post by **ocwd** » Thu Jul 23, 2020 12:27 pm

Thanks Wes. I didn't see the TM 9-804 in the downloads section. I'll see if I can get a copy somewhere.

ocwd · Post by **ocwd** » Thu Jul 23, 2020 12:29 pm

That was easy.

https://radionerds.com/index.php/File:T ... 8_JEEP.pdf

Post by **wesk** » Thu Jul 23, 2020 1:11 pm

How did that manual work for you? There is even one more manual, the factory service manual for the six pilot vehicles (prototypes) M38’s listed specifically as US Army registration numbers 2368159 thru 2368164. There is no date on the publication but most likely circa April 1950.

ocwd · Post by **ocwd** » Thu Jul 23, 2020 2:09 pm

The TM 9-804 looks like it has great information. Pages 28-32 have good descriptions of vent line routing. I'll see if I can locate the Factory Service Manual.

Thanks for the information.

ocwd · Post by **ocwd** » Thu Jul 23, 2020 2:19 pm

Wes,

Are you talking about this one? I didn't find a pdf but I have an original copy at home I can look through.

ocwd · Post by **ocwd** » Thu Jul 23, 2020 2:34 pm

Nope, I'm guessing this is it.

Post by **wesk** » Thu Jul 23, 2020 8:26 pm