actaeon9
Seaman Apprentice
- Joined
- Sep 22, 2008
- Messages
- 32
Hi All,
I'm trying to assemble a DIY checklist (or flow chart if you will) of items/tests to perform on my 1988 165 mercruiser w/alpha one for excessive heat.
The story: Last year, due to an improperly installed motor before I owned the boat, the oil pan rubbed on the stringer, and finally rubbed through the pan. I had the motor removed and pan fixed, and it was installed with new motor mounts and other odds and ends. Nothing was done with the fresh water cooling system during this work. (Cooling system had always worked fine, I had the impeller and raw water pump done two years ago, along with the heat exchanger checked).
I put the boat in the water for the first time this year, and it (as normal) heated up to about 165-170. As I continued to run at cruising speeds, it continued heating up well past 180 (into the 190s). I finally decided to take it out before we got anywhere near 200. I then start looking through the system, and found that the raw water intake hose (from the foot to the gimbal housing) was corroded, cracked, and leaking cool (raw) water. I had this hose replaced and thought the problem to be fixed. I then took the boat back out, and it displayed the same behavior. So here I am, having spent 2K on the motor being fixed, plus fixing the intake hose, and it's still heating up.
I went out and purchased an infared thermometer last night, and I intend to start troubleshooting the problem. I was told by my mechanic that sometimes when he removes and re-installs old motors, the old gauges can do funny things. Does anyone have any suggestions on the steps to take from here? Where should I test the temp with the infared? I thought about starting with the thermostat, but can't find it? The seloc manual shows a picture of the coolant resivoir, and explains how to change the thermostat, but never shows where it is?
Thanks in advance for any suggestions -
I'm trying to assemble a DIY checklist (or flow chart if you will) of items/tests to perform on my 1988 165 mercruiser w/alpha one for excessive heat.
The story: Last year, due to an improperly installed motor before I owned the boat, the oil pan rubbed on the stringer, and finally rubbed through the pan. I had the motor removed and pan fixed, and it was installed with new motor mounts and other odds and ends. Nothing was done with the fresh water cooling system during this work. (Cooling system had always worked fine, I had the impeller and raw water pump done two years ago, along with the heat exchanger checked).
I put the boat in the water for the first time this year, and it (as normal) heated up to about 165-170. As I continued to run at cruising speeds, it continued heating up well past 180 (into the 190s). I finally decided to take it out before we got anywhere near 200. I then start looking through the system, and found that the raw water intake hose (from the foot to the gimbal housing) was corroded, cracked, and leaking cool (raw) water. I had this hose replaced and thought the problem to be fixed. I then took the boat back out, and it displayed the same behavior. So here I am, having spent 2K on the motor being fixed, plus fixing the intake hose, and it's still heating up.
I went out and purchased an infared thermometer last night, and I intend to start troubleshooting the problem. I was told by my mechanic that sometimes when he removes and re-installs old motors, the old gauges can do funny things. Does anyone have any suggestions on the steps to take from here? Where should I test the temp with the infared? I thought about starting with the thermostat, but can't find it? The seloc manual shows a picture of the coolant resivoir, and explains how to change the thermostat, but never shows where it is?
Thanks in advance for any suggestions -
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