Heavy<313>
Seaman Apprentice
- Joined
- Jul 9, 2016
- Messages
- 36
I've been trying to track down an over heating problem in my 2000 Bayliner Capri 1952.
I bought this boat and it had been a couple years since it had seen the water I then performed the following service:
Changed oil (nice clean looked brand new)
Drained gear oil from lower unit and replaced impeller reinstalled lower and refilled with new gear lube
replaced sparkplugs, sparkplug wires, dist cap etc
Drained and refilled gas
Started boat up on muff's let it fast idle until it warmed up (verified water pumping good out of low pressure exhaust)
Hit the lake and as soon as I brought the boat up on plane it started overheating, bringing it back down to idle did not lower the temps much, limped back to ramp and pulled the boat out. Upon arriving home put boat back on muffs and pulled the raw water feed from the tstat housing and started the boat... no water at all.
Dropped lower unit again and found the freshwater pipe burst along with the guide tube melted.
Replaced thermostat with 160 degree unit Started boat up on muff's let it fast idle until it warmed up (verified water pumping good out of low pressure exhaust) Boat temp hovered around 175 I thought it was kinda high for a 160 degree thermostat but I could see it cycling up and down so thought it was okay.
Hit the lake again and it again overheated with almost no cool down when back to idle
Got back to the house and checked on muffs again and this time water flowing correctly from raw water feed hose.
I have ordered a new exhaust flapper valve and will be replacing that this week.
Last night I took out the stat and tested it in the kitchen with a meat thermometer. It opened very slightly at 160 and seemed to be fully open at 170, I then reinstalled it and run the boat in a tub with water supplied via a hose to keep it full. I idled the motor high enough to get water out the propeller opening, this time the boat barely broke 160, however I noticed something I think is weird, water was only coming out of one side of the low pressure exhaust, however exhaust was definitely coming out both sides.
So my question is might I have a blockage by the port low pressure exhaust or is it normal to only have water out of one side? Also is there anything I might be missing in troubleshooting this overheating underload issue?
I bought this boat and it had been a couple years since it had seen the water I then performed the following service:
Changed oil (nice clean looked brand new)
Drained gear oil from lower unit and replaced impeller reinstalled lower and refilled with new gear lube
replaced sparkplugs, sparkplug wires, dist cap etc
Drained and refilled gas
Started boat up on muff's let it fast idle until it warmed up (verified water pumping good out of low pressure exhaust)
Hit the lake and as soon as I brought the boat up on plane it started overheating, bringing it back down to idle did not lower the temps much, limped back to ramp and pulled the boat out. Upon arriving home put boat back on muffs and pulled the raw water feed from the tstat housing and started the boat... no water at all.
Dropped lower unit again and found the freshwater pipe burst along with the guide tube melted.
Replaced thermostat with 160 degree unit Started boat up on muff's let it fast idle until it warmed up (verified water pumping good out of low pressure exhaust) Boat temp hovered around 175 I thought it was kinda high for a 160 degree thermostat but I could see it cycling up and down so thought it was okay.
Hit the lake again and it again overheated with almost no cool down when back to idle
Got back to the house and checked on muffs again and this time water flowing correctly from raw water feed hose.
I have ordered a new exhaust flapper valve and will be replacing that this week.
Last night I took out the stat and tested it in the kitchen with a meat thermometer. It opened very slightly at 160 and seemed to be fully open at 170, I then reinstalled it and run the boat in a tub with water supplied via a hose to keep it full. I idled the motor high enough to get water out the propeller opening, this time the boat barely broke 160, however I noticed something I think is weird, water was only coming out of one side of the low pressure exhaust, however exhaust was definitely coming out both sides.
So my question is might I have a blockage by the port low pressure exhaust or is it normal to only have water out of one side? Also is there anything I might be missing in troubleshooting this overheating underload issue?
