wakeboardbob
Cadet
- Joined
- Oct 9, 2009
- Messages
- 20
As per Don S suggestion I am posting a new thread to see if I can get some help troubleshooting a large temp difference on my risers/manifolds on a 2001 merc 5.0 efi alpha 1. I am recovering from an overheated engine(my fault) and cracked head. New impellar, circulating pump, relatively new risers/manifolds(less than a year old), water hose feeding thermostat housing was back flushed to transom. All remaining parts of shutters(only metal pieces) were pulled out the exhaust y pipe from the transom side after full outdrive was removed. When i shot the temp of the risers and hoses with an IR gun the problem seems to be originating at the thermostat housing where the riser hoses connect. There is a 30-40 degree difference right on the housing when the engine is running. I have spent some time searching the web and one poster said their dealer puts a chunk on slightly smaller size hose inside the port side riser hose and this balances the flow imbalance? Id rather not change what the engineers at mercruiser designed except for the fact that they themselves change their recommendations after the fact, thru service bulletins. I have been hearing about check balls on the older thermostat housing used to balance the flow too? Any suggestions would be appreciated as well as if someone knows the standard running psi for the water at the risers/manifolds, this should be an easy way to test if one side is getting more water?
