buddy needs help
 

hey guys me agian i was hoping someone could
help my buddy has a 31 ss searay with twin big blocks
454 magnums . he,s having a tempeture problem
with his starboard engine at cruise speed she runs
at 170 degrees 15 psi of pressure port engine runs at 160
at 25 psi .at no wake speed starboard engine will climb
to220 at 5 psi port engine will run at 165 5 psi he put a new
seapump and waterpump and thermostate. still no change.
now the problem started this year and all he did was change
exhuast system he put harden marine mufflers.flow coming
out the tips seams to be the same THANKS GUYS ANY INFO
WOULD BE PUT TO GOOD USE.

this is a puzzler but i would first check to make sure he didnt suck anything into the cooling system that may be blocking it. Check the powersteering cooler and the oil cooler if he has one. Also it may help to dril the (I think it was 2 x 1/8" holes) in the thermostat to relieve any steam pockets he may be getting.
If all he did was just put on mufflers then maybe he may have rust deposits in the exhaust manifolds causing some blockage??? I'm just throwing out ideas here....maybe some who has had the same problem can better help ya... :) Good luck

Recheck the hose clamps on the hose that goes between the transom intake fitting and the seawater pump--- YOu could be sucking air.

I would also suspect a p/s or oil cooler- they build up deposits in there and restrict water flow.

If they are Crusaders it is called a U-cooler and does both-they will clog.