3.8 water gushing from engine

robbies

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IMG_1234.jpeg1982 3.8 motor. When I hook up the muffs and run the motor, water starts gushing from somewhere under the lh side under the manifold around the engine mount. All the petcocks that I can find (4) are tightened. I have no visibility because of the fuel pump, engine mount, etc. Can't seem to find any good diagrams of the block water passages, etc. Any ideas? Could it be a water jacket/freeze plug? And if it is the freeze plug, what would cause it to leak?
The photo is the area directly below where the water is coming from. Thanks!
 

kenny nunez

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If a freeze only pushed out a core plug and did not crack the block you are 1 lucky person. The engine comes out pretty easy you just have to have the drive supported tying it to the top of the transom.
Remove the dust shield in front of the flywheel, disconnect the electrical, exhaust and throttle linkage. It just has 6 bolts on the rear and the lag screws under the front mounts. The engine only has to come forward about 1.5“s to come out.
 

Scott Danforth

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the GM 3.8 motors do not survive a thermal-declination-induced-phase-shift-hydro-expansion episode

core plugs are not for freeze protection. they are to get core sand out of the water passages at the foundry

only some ford models will actually survive a freeze event and not crack the block

I would pull the drive (remove trunion mounts)
remove the boot retaining ring
pull motor and intermediate assembly as a unit.
 

robbies

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A better question is how did you winterize it?
I took out 3 of the petcocks ( didn't see the one that is in the photo) and poured pink rv coolant in. didn't run the motor as I had no way to at the time. My first time trying. Previous maintenance unknown but supposedly winterized.
 

robbies

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So everyone seems to think it's coming from the water jacket/freeze plug? I don't see anywhere else that the water can be coming from.
Took the water exhaust manifold off and still can't find the plugs so I'm going to remove the fuel pump. Looks to me maybe the plugs are buried behind the engine mounts...
Starting to hate inboards. This is the second one I've had with a possible cracked block that I bought that way without knowing.
 

Scott Danforth

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So everyone seems to think it's coming from the water jacket/freeze plug? I don't see anywhere else that the water can be coming from.
Took the water exhaust manifold off and still can't find the plugs so I'm going to remove the fuel pump. Looks to me maybe the plugs are buried behind the engine mounts...
Starting to hate inboards. This is the second one I've had with a possible cracked block that I bought that way without knowing.
no, I think its coming from a busted block. the core plugs on the 229 are on the back of the block and on the front of the block. I do not recall core plugs on the sides of the block
 

Redrig

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Starting to hate inboards. This is the second one I've had with a possible cracked block that I bought that way without knowing.

I live in Utah and my local classifieds are littered every spring / summer with boats with cracked blocks.....sometimes nice ones too.

Are there any rust trails that you can see from the general area ?
 

robbies

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MYSTERY SOLVED. It was in fact the core/freeze plug behind the motor mount. Saw it laying there in the cavity. Couldn't get in there to pull it out though to take a look at it.
Since there is no water in the oil the plan is to replace the plugs WITHOUT removing the motor. I'm able to get a small engine jack underneath the block so I can just remove the engine mount for access.
If this doesn't work I will probably destroy everything in sight and never deal with boats again.
 

robbies

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I live in Utah and my local classifieds are littered every spring / summer with boats with cracked blocks.....sometimes nice ones too.

Are there any rust trails that you can see from the general area ?
Found it. It's the plug.
I think every single boat should have a non-removable tag in multiple places stating that it is REQUIRED for your boat that you winterize it and the procedure on how to do so. And also what will happen if you don't. So many newbies (including me) that had no idea.
 

robbies

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no, I think its coming from a busted block. the core plugs on the 229 are on the back of the block and on the front of the block. I do not recall core plugs on the sides of the block
It is the core plug. I found it laying behind the engine mount. I think this is the exact block.
1652288245370.png
 

Scott Danforth

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I think every single boat should have a non-removable tag in multiple places stating that it is REQUIRED for your boat that you winterize it and the procedure on how to do so.
its in the manual
 

Lou C

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Those angled drain fittings have a way of clogging up, I have that on my 4.3 and have had to dig it out a few times to get it to drain. They used that because of the size of the big old direct drive Delco starter, if you replace with a PMGR starter when you get a reman block, you can eliminate it because it's not needed with the smaller starter. I left mine because it drains, and sometimes it's better to let sleeping dogs lie....PMGR Arco installed.jpg
 

kenny nunez

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The last Buick V6 was used by OMC in 72. From 73 to 86 all OMC engines were light blue. It is in fact a 3.8 chebbie. I Re powered a few of boats with that one. The core plug could be replaced by a expanding rubber one available at any auto store. Good luck.
 

robbies

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UPDATE:
Installed an expanding rubber freeze/core plug successfully. Ran the motor on the lake with no leaks, engine temp steady at 150, and best of all NO WATER IN THE OIL. This leads me to believe that despite conflicting opinions all over the web, that the freeze plugs (at least on boats) ARE designed to pop out to possibly save the block from cracking. Or I'm just one lucky bastard. Either way, time will tell.
Thanks to all for your input!
 

Scott Danforth

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Or I'm just one lucky bastard.
this. now buy a lottery ticket

because if you had a freeze event on a GM block and it just pushed the core plug out and did not crack the block, you are the only one

on some ford blocks, the blocks are built a little stronger and it can happen, not on a GM block
 
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