steviecops
Chief Petty Officer
- Joined
- Oct 3, 2003
- Messages
- 585
Hi<br />Can anyone figure this one out?, because I can't 
<br /><br />I fitted a new thermostat to my 1980 55 Johnson last week, and took my boat out today for the first time since fitting the new stat.<br /><br />From cold, the engine started and warmed up pretty quickly. I watched the exhaust relief ports and if I'm right, when the stat opened, water spray started coming out of the relief ports. I felt the head and could keep my fingers on there for no more than 2 seconds, and the engine was idling better than it has since I've had it, so all seemed well.<br /><br />I motored out to my fishing mark which took about 20 minutes. No problems. Shut engine down and fished for 1 hour. Re-started engine, no problems, then motored to another fishing mark for about 15 minutes at WOT. <br /><br />When I got there, I slowed to idle speed to scan the sea bed with fishfinder and after about 2 minutes, the hot alarm buzzer went off <br /><br />I shut the engine down straight away and dropped the anchor. I checked the buzzer every few minutes and after about 5 minutes I could turn the key without the buzzer sounding. Fished for another hour, then went to move to a different mark. Started engine and let it idle while I retrieved anchor, when I went to move off the buzzer sounded again <br /><br />I started my auxillary engine and started to make my way back to the dock. After about 10 minutes, I started the main engine again, no buzzer sounded and I was able to run all the way back to the dock without the buzzer sounding again <br /><br />Does anyone have any idea why the buzzer is sounding sometimes, and not others? Will running at WOT, then letting the engine idle in gear cause the engine to overheat? Why did the buzzer go off the second time when the engine had only been running for a few minutes?<br /><br />Also, after the buzzer sounded the first time, I took the cover off to have a look. I could only keep my fingers on the head for one second now without getting burnt, and the top of the flywheel felt hot too, although I could keep my hand on it without getting burnt, just. <br /><br />Should the top of the flywheel get hot at normal running temp?<br /><br />Sorry for all the questions, but I'm on the verge of taking the ^*~#@!! thermostat out. I never had these problems when my engine ran cold. I think I'd rather put up with the rough idle than risk ruining my engine.<br /><br />Any help would be much appreciated.<br />Thanks<br />Steve
<br /><br />I fitted a new thermostat to my 1980 55 Johnson last week, and took my boat out today for the first time since fitting the new stat.<br /><br />From cold, the engine started and warmed up pretty quickly. I watched the exhaust relief ports and if I'm right, when the stat opened, water spray started coming out of the relief ports. I felt the head and could keep my fingers on there for no more than 2 seconds, and the engine was idling better than it has since I've had it, so all seemed well.<br /><br />I motored out to my fishing mark which took about 20 minutes. No problems. Shut engine down and fished for 1 hour. Re-started engine, no problems, then motored to another fishing mark for about 15 minutes at WOT. <br /><br />When I got there, I slowed to idle speed to scan the sea bed with fishfinder and after about 2 minutes, the hot alarm buzzer went off <br /><br />I shut the engine down straight away and dropped the anchor. I checked the buzzer every few minutes and after about 5 minutes I could turn the key without the buzzer sounding. Fished for another hour, then went to move to a different mark. Started engine and let it idle while I retrieved anchor, when I went to move off the buzzer sounded again <br /><br />I started my auxillary engine and started to make my way back to the dock. After about 10 minutes, I started the main engine again, no buzzer sounded and I was able to run all the way back to the dock without the buzzer sounding again <br /><br />Does anyone have any idea why the buzzer is sounding sometimes, and not others? Will running at WOT, then letting the engine idle in gear cause the engine to overheat? Why did the buzzer go off the second time when the engine had only been running for a few minutes?<br /><br />Also, after the buzzer sounded the first time, I took the cover off to have a look. I could only keep my fingers on the head for one second now without getting burnt, and the top of the flywheel felt hot too, although I could keep my hand on it without getting burnt, just. <br /><br />Should the top of the flywheel get hot at normal running temp?<br /><br />Sorry for all the questions, but I'm on the verge of taking the ^*~#@!! thermostat out. I never had these problems when my engine ran cold. I think I'd rather put up with the rough idle than risk ruining my engine.<br /><br />Any help would be much appreciated.<br />Thanks<br />Steve