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| Holes in block | |
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| Tweet Topic Started: Jan 10 2018, 03:04 PM (138 Views) | |
| SteveK | Jan 10 2018, 03:04 PM Post #1 |
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Does anybody know what the three holes in the back of the block are for, and if threaded or not, and what size and thread they are? Two on the driver's half are from lower left upward right about 2.5 inches apart, and the third is up high and towards the passenger's side edge. All seem to be about 1" in depth, and feel like maybe there are threads in there, and smaller than a 1/4" bolt. I'm concerned they are into the water jacket area and need to be plugged up. I've never had the block filled with water. Thanks for any help. |
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SteveK 62 Dispatcher South Florida | |
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| Rus Curtis | Jan 10 2018, 05:32 PM Post #2 |
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Steve, Not sure if you're referencing an F-head or L-head but I believe both blocks have the holes in the same locations. I don't believe the holes enter into the water jacket as mine weren't used at all until I started my rebuild and added the correct bracket. Here's what I can find. F-head uses one hole for the Crankshaft to Head Oil Line bracket: http://cj3b.info/Photos/Parts/EngineFig77.JPG Number 6 and 7. If I'm looking at my parts manual correctly, the F-head bracket uses a 1/4" - 20 x 1/2" (the bracket isn't too thick) The L head on Cj2A Forum here: https://www.thecj2apage.com/forums/engine-pictures_topic36893.html scroll down to dgreen6655's post and look at his second image. It shows a throttle link bracket using two of the holes and nothing in the other. Another really good image: https://www.thecj2apage.com/forums/throttle-linkage_topic31933.html scroll down to bkruetz's post - same two holes used other empty. Notice the orientation of the bracket itself is flipped between the two engines. I don't know about the hole on the passenger side but would guess it would have a similar function (maybe a RHD model?). I would also make the assumption that all holes are the same size/thread and depth. |
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Rus Curtis Alabama '54 CJ-3B "Green Gruntt" Bantam T3-C | |
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| SteveK | Jan 11 2018, 02:48 PM Post #3 |
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Thanks Rus, that's good info and pics. That throttle linkage looks much sturdier than the DJ pivot on the valve cover mount, but I'm told the rotation of the carburetor 90 degrees is why the linkage changed. What has also come up in conversations in comparing blocks looking at those holes, is the differences in the back whether it has a freeze plug or not. My 62 does not. I wonder if anybody knows when that change started? I saw a picture of the new cast Willys block made via computer from "specs", and it has the freeze plug hole in the back and the three little ones too. Sorry, I can't post pics. No one seems to know what the third one was intended for, as every pic I've seen so far has it vacant whether there is a throttle bracket or not. It obviously doesn't have access to the water jacket if nobody is plugging it. Thanks again for your response. |
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SteveK 62 Dispatcher South Florida | |
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7:29 PM Jul 10