Engine block weld mystery

[lhfarm]

While reading the post on cast iron welding, I wondered if some of you might help with a mystery Willys Jeep engine block. The block was cast and assembled in June of 1945. It most likely started life as a military engine that used a chain for the cam. There is one clue that it might have been re-purchased after the war by Willys to be used in a civilian jeep. At some point the block was modified to allow the newer gear driven cam to be installed.

I purchased this engine completely disassembled and stored in a box. The seller hasn't been able to supply any history and the guys on the jeep forums can only say it is a one of a kind block. There are no factory serial numbers, but there are punched numbers on the side of the block with what may be a date of 8-29-48.

Here are some pictures of the addition to the block that were needed to allow the geared cam. The section of the block where the addition was added would have been straight across. The later blocks, made for the geared cam would have a longer area, that then stepped down. In the first, you can see what appears to be a bead where the added piece of cast was added. The others are side shots of the modification.

This is a beautiful piece of work. I want to believe it was done at the factory or by someone who had the skills to make this look like an original part of the block. The 1948 date (if it is a date) is long after the change over to the geared cam model. But I'd like to believe this was a special block, maybe even a prototype from 1945 or 46.

Would a local machine shop welder have been able to make this modification in the late 40s or is this something that would have been done in a specialized environment?

Thanks

 

[yomax4]

In the 40's there were similar rods as the ones we have today. Some may have been better. The pic's look like the repair was done with a stick rod. Another product from those days that was used a lot was actually a 1/4" square 18" long stick of actual cast iron loosely cast into sticks. Kind of fragile. They used a flux to break the surface tension and applied the cast stick like a brazing rod. Still being used today. It's called Kast-Weld 111 with Kast-Weld Flux. This stuff works well on thicker cast. You can vee out the crack or break, Apply the flux and lay pieces of the rod on the vee and it melds itself right into the origional casting. Just another tool for the cast repair guy..Some old timers used to strip stranded copper wire and wrap the copper around the stick to restore some of the copper that was lost in the brazing process. Fun stuff..I have a few dozen sticks left.

 

[lhfarm]

Thank you! This is just what I needed. With your permission, I'd like to share your response on the jeep forum. While I was sure the perfect piece of added cast meant it had to have been done at the factory, I now know better.

Why the block was modified still remains a mystery. There doesn't appear to be a major improvement of engine performance going from chain to gears. To change from chain to gears only involved adding the gears to the crank and cam and modifying the block. We will probably never know why the owner choose to do so.

For now, I'll stop chasing the idea that this was a very special block. Instead, I'll just admire the workmanship that went into the modification.

 

[yomax4]

Yeah, If you look at the face area on the block you can see the weld was machined down partially. It just looks like stick rod repair to me. I'm trying to think why the switch to gears myself..Could it be because of a front PTO or Winch? no clue.

 

[lhfarm]

The PTOs (front and/or rear) are add-ons to the tranny. Hydraulic pumps were driven off the front of the crank, but that was all external. No one has come up with a good reason for the change.

 

[Scotty Dive]

When you mentioned the jeep forum - was it the 3b forum? If not - try over there for additional history - those guys are unbelievable with their website and depth of knowledge.

The CJ3B Page

 

[lhfarm]

When you mentioned the jeep forum - was it the 3b forum? If not - try over there for additional history - those guys are unbelievable with their website wand depth of knowledge.

The CJ3B Page

Yes, a great site. I've been on the TheCJ2Apage.com everything about the Willys CJ2A Jeep and also the G503.com is Military Vehicles, The WWII Military Jeep, Parts, Olive Drab and All Related Things. forum. Both have a group of guys into "older" jeeps. I spend time on the 3b page for farm jeep related items.

You can read about finding the motor and what the 2a guys have to say over at Farm Jeep (click on the latest blog listing).