888 drain holes

[iand464]

I have a mercruiser 888, there are two block drains on the block, previous owners have put drain valves there. Last year I pulled the valves out to winterize. I also noticed on the starboard side of the block there was a brass plug right in front of the starter. I pulled that out. No additional water came out of it. The plug was a 1/8 npt thread and was all messed up, so I bought a new one. I went to put it in and it's not a 1/8 not threaded hole, but a 7/16 - 14 thread, smaller than the block drain threads. What is this hole for? Do I even need a plug there?

 

[Bt Doctur]

not familiar with the ford motors

 

[iand464]

the hole is right below the last core plug on the starboard side.

 

[Bt Doctur]

http://i39.tinypic.com/4lg29w.jpg

http://351winsor.com/joel/Engine_Diagrams_Pics/302fordblockcasting.gif

 

[iand464]

It right next to the a in at the end of the casting number on the second photo. It has nothing in it on the first pic. Crawling under a neighbors old f150 also had nothing in that hole. It looks lower than the water jackets anyways. Someone threaded the wrong plug into a hole that goes to nothing and isn't used. Thanks for your help

 

[Bondo]

It looks lower than the water jackets anyways.

Ayuh,.... Is it a blind hole, a dead-end,..??

It could be a dipstick hole to the base,.....
If so, a plastic plug will stop an oil leak from it,.....

 

[iand464]

I think it's a dead end at this point, nothing but rust in the bottom of it. Dipsticks go through the pan on truck 302s and through the timing cover on mustangs. I don't think there is a provision for it in the block. I'll know for sure when I launch her this weekend! It's full of dry rust so it's not an oil passage galley.