While I was puttering around with my block , I thought that the misalignment in passages at the bottom of the oil filter boss was an area I could clean up..........enhance flow , remove restriction etc.
Got a little carbide burr and the trusty die grinder.
Started cleaning the junction of where the drill bits path intersected.
It looked good.........just a little more radiusing in the bottom and &&*%$#$$#@%&^%$!!!!!
It is into the water jacket.
I am thinking that Ed Justice makes a product that may save me........metal filled epoxy.
But I'd love to hear some ideas from the experts.
Not ideas about my lineage and intellectual capacity ( or lack there of ).
Will the miracle in a tube work ?
plan "C" would be to go with an external pump and block off the filter boss entirely , but that would set me back about a week's wages , so I am hoping that one of you can save me on this.
Thanks !

John when I worked for Cummins we used a product called Devcon. We used it to repair cracks in cast iron blocks and decks on some very big engines in severe environments. Once it was hard it could be drilled, machined,etc. Hard part would be getting it in wear you need it.

I think I can get behind the area with some stiff wire and a bend or two.......try to make a miniature putty knife type end on it to work it from the back side........from the top won't be a problem I think.
If I can get it spread out on both sides of the hole , I think I would be O.K.

devcon has been around for a long time. used it back in the 80's and repaired a v12 detroit water jacket with it . (under the cam.) as far as I know its' still running with no leaks.

PM RyanJ. I'm sure he has dealt with plenty of water jacket leaks on R3 blocks.

I have soldered water jacket holes shut on cast iron for the past 20 years. With the right liquid flux and solder it works good.

I have two water jacket holes in the intake ports on my cast iron heads soldered shut now.

Ryan had them pressure tested and they were fine.

If you use epoxy whatever you use better not loosen up once its soaked with the engine oil.

That would be my main concern.

I dont know, you have oil and water going on ther. Can you thread the hole and send a plug down in it with a sealer and re port it.

Ive never used the devcon stuff and Im not sure I would trust any Epoxy that I know of from the looks of it. Id send a combination of some kind of interference plug and sealer/solder down there and regrind for flow. mike

Weld it.Just zap it with a stick weld 99 or 55 Econocast rod or mig wire N-55,dress it up and pressure check.

What s going on here, yesterday you were a genius ...
don t trust the epoxy, water in your oil kill your crank in no time, don t ask...

Common problem.... especially on race blocks, casting is too damn thin in that area. Usually safe to do that mod on a factory block, but not so much on race block. I dunno how many people I've had to walk through that repair on phone over the years.....

You don't need a $700 external pump to fix it... That is just an oil inlet for on block oil filter. You really should just switch to an external oil filter...... You are doing a W9 motor, you should not be using filter on side of block anyhow, you should be pumping oil into front R3 priority main oil feed.... I know, not as "clean & simple" as on block filter, but there is "clean & simple" & then the better way to do things.....

The filter thread inlet on block is 3/4" fine thread.... go to hardware store & buy a 1" UHL 3/4" fine bolt.... & you'll need to get a 1/2" NPT drill/tap, & a 3/8" NPT drill tap to do nice clean simple repair..... Enlarge the current 3/8" NPT hole in bellhousing area that was an access hole for that hole you just messed up to be machined.... it's in all SB Mopar blocks, & gets a 3/8" NPT plug normally..... well anyhow, enlarge that to 1/2" NPT to allow you room to access inside area with drill/3/8" NPT tap (might need a 3/8" NPT "extenson tap" like 4" long one is what I have.... & then just tap block internally to 3/8" & put a plug in there. So plug it there with sealer, & put sealer on 3/4" bolt & use it to plug the large center hole, don't worry about fixing hole in block & allow water to flow out into that now small oil passage that is plugged on both sides once you install bolt & the new 3/8" internal plug.....

Then drill/tap your oil pump outlet hole on side of block (lower of two holes on left side of filter boss) Put 3/8" NPT plug in upper hole just like normal, & then put an AN fitting out of the pump outlet hole, run line to your external filter boss (CV products makes nice one) & then pump oil put of filter mount & into priority oil feed @ front of block. Done..... no epoxy to worry about etc. Everything sealed up with NPT plugs & fine thread bolt with sealer. No leak, no worries & better oil system to boot VS using filter on block deal.

I love a happy ending

Thank you Ryan ........... p.m.'ing you was next on list of things to do.
It is funny , I was trying to wrap my brain around possible fixes and was going to look at plunging in the 3/4" hole with an end mill to create a seat , then use a threaded sleeve to seal it off and drill from the back of the block to restore the oil path.
But I am both excited and relieved to hear your fix.
It sounds too easy .......... which puts it within my range of skills.

If you can use a drill & a tap, you can fix it LOL

God I love MP race blocks...

I had one late last year I built for guy in FL. It did not get ran/dynoed here, just primed it on stand, crated it & shipped out....Primed fine, no problems with block..... I had not modified that area in any way, so was just right as machined from MP.... He put in his Dragster & fired it & found water mixing W/ oil almost immediately. He calls me & says what should I look for? I knew exactly where to look... told him pull filter & plate off & look close in that machined corner where the 2 drill bits meet & bet he finds a blown through pin hole there, sure enough, that's what it was. He did the NPT trick with little extra precaution since motor was already together, like shoving bearing grease up the oil passages to prevent shavings from getting where should'nt & works fine to this day.

The R3 in my SuperBee I was not so lucky, I found motor oil pouring out my freeze plug holes when priming it on stand with center feed water lines unhooked.... That one had vertical oil passage for 1/8" pressure gauge sender machined @ angle right into water jacket.... had to completely tear that one back down to bare block to fix it. It was 20 minutes from putting on dyno for fire up when found problem............ fun fun.

Takes about an hour to setup & press test both sides of a block.