Re: 1987 3.0 omc
if the exhaust elbow is cracked will it allow water back in to the engine
Howdy,
Not usually.
If the elbow is internally cracked, it usually only allows water back into the exhaust and open an exhaust valve only AFTER you shut down.
When you try to restart the engine later, it will usually hydro-lock during cranking until the water is either pushed past the rings and/or out the exhaust. (Very little water actually gets past the rings though....and the little that does is usually evaporated out during running)
When it's running the exhaust gases continuously push the water out....so water cannot get into the engine oil that way.....
If you still have water in the oil after running you have other possibilities:
1. You didn't get all the original water out of the pan.
2. You have a cracked block. Look in the lifter area under the cover. 3.0L engines crack there sometimes.
3. cracked head. (yes I know you just replaced the head)
If you have not pressure checked the cooling system, now would be a good time to do it.....
A pressure check will definitively reveal cooling system leaks.
Regards,
Rick
