1950 plymouth 218 oil pressure relief valve

[Notg15]

I am trying to put my engine back together after getting it back from the machine shop. I decided to check the oil pressure valve to make sure it wasn’t stuck. Unfortunatly it is and I have tried a hook pick screw drivers and even heat and an easy out. She’s stuck, does anyone have any advice? 

[P15-D24]

I've used on of those tools for removing broken irrigation risers, like this: https://www.truevalue.com/pro-series-underground-sprinkler-nipple-extractor-1-2-in?ctplacement=153825-44622122499

 

[johnsartain]

I used a 1/4" pipe tap chucked in a 1/2" drill. I didn't care what happened to the drill as I had to peck it on the end with a hammer to get the pipe tap to bind in the relief valve. Once it bound up and started spinning the valve, it was a matter of pulling back slightly on the drill while it spun. I tried the nipple extractor route, but I didn't have any luck with mine it was frozen solid. The metal that the relief valve is made of is very hard. I was to the point that I was considering using a welder to attach a welding rod to the valve and then using a slide hammer to pop it out. I didn't have to go that far. I was worried that there may be too much heat or there may have been an arc that welded the piston to the block.

I have another block I want to build for a backup engine. The screw plug over the relief valve is frozen in its threads and won't come out. I have tried heating it and wrenching it several times with no luck. Any suggestions here?