Exhaust Manifold Water Ports

[Mr. Bunz]

I just purchased an older Searay SRV 193 WITH A Mercruiser 5.0 with the 90 degree risers in the back of the exhaust manifolds. On the side of either manifold there is a small hole that water drains from. What is suppose to fit in there. By the way this is my first inboard.

 

[Bondo]

Ayuh,..... Welcome Aboard,..... I'm Guessin' yer lookin' at a manifold Drain,.....

If so, it'll be threaded, 'n accept a 1/4" pipe plug,....

 

[Mr. Bunz]

I tried threading a 7/16 bolt fine thread and corse thread and it didn't seem to fit. 1/2" and 3/8" doesn't fit.

 

[Rick Stephens]

I tried threading a 7/16 bolt fine thread and corse thread and it didn't seem to fit. 1/2" and 3/8" doesn't fit.

THat's because pipe thread is different from bolt thread. Pipe thread is tapered too.