LuckyPenny
Petty Officer 1st Class
- Joined
- Feb 21, 2003
- Messages
- 256
I have a 1977 Mercuriser 250 (5.7L) with a raw water cooling system. while checking the cooling system I opened the therostat housing to check the therostat and noticed a good size bye pass. It seems to me that it is a bit large and wondering how the engine reaches temp. should this be blocked on the raw water system and left open in a closed system?
