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While my engine is out at the machine shop I thought I'd use the opportunity to ditch two civilian-style universal pipe hangers the previous owner used in favor of the proper M38 brackets.

My question: on page 91 of the ORD9 there's a SPACER, Support Bracket to Frame (used on vehicles after 27690), G740-8328138, WO-666619.

This spacer is also mentioned in the TM9-8012 on page 173, paragraph 138.b.(1), "Remove the nut, bolt, and *spacer* securing the exhaust pipe extension support bracket to the frame cross member."

That bracket has a MB/GPW G503 part number (G503-7371047) but the spacer has a G740 part number, which makes me think it's necessary to properly hanging the exhaust system on the M38.

I noticed the screw length change for serial numbers after 27690 for the bracket in the ORD9 --- from 5/8-inch long to 1-1/2 inch long, which seems to point to a spacer length of maybe 3/4 inch?

No joy researching anything further about this spacer, in the M38 Reference Guide, this forum, or others.

Can anybody point me to a better description. dimensions, and maybe a photo of this spacer?

As always, thanks!

My 5-52 M38 is as released from Fort Jackson SC and its has the spacer on the long exhaust pipe you are referring to. It looks a lot like one of the six spacer as used on the engine front pulley shield.

That bracket has a MB/GPW G503 part number (G503-7371047) but the spacer has a G740 part number, which makes me think it's necessary to properly hanging the exhaust system on the M38.

I noticed the screw length change for serial numbers after 27690 for the bracket in the ORD9 --- from 5/8-inch long to 1-1/2 inch long, which seems to point to a spacer length of maybe 3/4 inch?

The bracket ORD# 7371047, WO# A15498 was used throughout M38 production. This kind of makes your point why the spacer was needed as invalid. The Late 55 ORD 9 shows the bracket as original and the spacer & bolt were introduced at serial MC27691 (August 51). The early Nov 51 ORD 9 does not mention the spacer at all. As you noted the 1956 TM 9-8012 mentions the spacer but the early M38 operator's manual TM 9-804 dated Sep 50 does not.

This makes for an assumption that something about that bracket and extension pipe had a clearance issue and the spacer was added at the factory in Aug 51 while still using the same bracket.

Now since the bracket (ORD# 7371047, WO# A15498) shows the part as first used on the G503 jeep let's look at the part history there.

G503 ORD 9 1949
Under Deep Mud Exh (Rear bumper exit)
Bracket PN WO# A15498

G503 ORD 9 1945
Under Deep Mud Exh (Rear bumper exit)
Bracket PN WO# A 15498

MB IPL TM 10-1186 1943
Only shows short side exit exhaust system.

The only rear exhaust difference between the M38 & the G503 WWII post 1943 rear exit exhaust system is the extension pipe part # A9142 for the G503 & 649868 for the M38. So my money money says the spacer was added because something rubbed against something.

Great lead Harold, thanks! Any chance for a measurement of the length and/or a photo?

I double-checked the ORD9 and the spacer part number is only used once on the truck, for this bracket. (No luck that it would be the same as the pulley guard spacers --- which I have and could measure).

I'd really like to nail down the spacer dimension. Having it might be the difference between correct pipe alignment and all the "tweaking" I've read folks had to do in some other posts in this forum (their photos show no spacer on their bracket). I'd rather not have to experiment if you can measure the real deal for us?

See: http://willysmjeeps.com/v2/modules.php? ... haust+pipe

and

http://willysmjeeps.com/v2/modules.php? ... haust+pipe

I also came across what looks like an error in the manuals (or at least I'm confused). The ORD9 says the "triangle" shaped flange bolts (3 each, two flanges, 6 total) are 5/16-24 x 1-inch bolts with self-locking nuts. The TM9-8012, paragraph 138, says 3/8 x 1-1/2-inch bolts. The flanges on my truck are 3/8 holes and have 3/8-24 x 1-inch bolts. One inch being plenty long. I'm guessing the ORD9 says 5/16-24 x 1-inch but should be 3/8-24 x 1-inch.

Thanks again!

And thanks also Wes! I figured the spacer was there for a reason.

Follow-up post in the search for my elusive SPACER for the exhaust pipe hanger.

Many thanks to Harold (45auto) for taking the time to search his files for this photo of his original unmolested M38, including permission to use it here. The original is in his album. Thanks Harold!

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The photo also revealed another key piece of information for me --- the direction that the clamp is oriented on the frame. Easy to see it makes a difference in where the pipe hangs --- dress left or dress right.

I don't have an exact measurement of the length of the SPACER, but guessed 3/4-inch zooming in on the photo (might maybe 5/8-inch?), so I picked one up today for $3.19 at my local Ace Hardware (Hillman part number 58589-L, 5/16 ID, 5/8 OD, 3/4-inch long). The 1/2-inch was obviously too short and the 1-inch too long (no other choices available).

I won't know for sure how it hangs until I get my motor back from the machine shop and put it all back together again. More to follow.....

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A lot of the dress right & left will fall under the twist of the pipe and which dress will get the muffler under it's hanger.

Absolutely!

I have re-pop pipes and muffler, and although in good shape, there's no telling how early or late they might be or who made them (pretty sure they aren't NOS).

Because the previous owner slung them using flexible civvy hangers I'm hoping he didn't also "tweak" the pipes to make them fit. I sure as heck don't want to buy a new exhaust system in order to find out! I'm going to take some time twisting, turning, and clamping before I consider bending anything.

Came across and lifted this photo from what appears to be a fairly unmolested matching numbers M38 currently for sale in York, SC.

Perhaps it reinforces evidence of the spacer for the pipe hanger bracket, including the bracket orientation on the frame:

Since engine serials never matched chassis serials in Willys M jeeps just what exactly is a

unmolested matching numbers M38 currently for sale in York, SC.

!!!

I realize a lot of folks over the years have stamped new dash plates to match engine serials and stamped new engine serials to match dash plates but that is all easily discernable on a pre-purchase inspection.

So which numbers are the seller saying matches?

Hi Wes,
He says: "I am selling this Jeep for my father who is 89. He has had this Jeep for many decades, but never got around to doing anything with it. It is all original from what I can tell and untouched except the head from the motor was stolen many years ago. Matching Numbers: The Vin behind the passenger seat, the vin on the dash plate, and the vin on the title all match. The engine block vin locations show no indication of having ever been stamped or the vin has completely rusted away. Sold As Is."

Here's a link to the For Sale page where everybody can read for themselves what he's saying.

https://www.ebay.com/itm/1952-Willys-M3 ... Sw3Jxcol7p

I'm fighting the temptation to go talk to the man. Six hour round-trip.