Home |
Search |
Today's Posts |
|
#1
|
|||
|
|||
Merc 5.7 carb/ alpha 1 - Overheating
Went over a large wave yesterday and directly after that I noticed the water
temp was over 200. Out of habit I scan this and the other essential gauges regularly when running. Up to that point the temp was the normal 160-170. I went to idle and then turned the engine off since this happened once before where I probably picked up a plastic bag wrapped around the water intake on the i/o. I raised the drive and felt around the intake holes searching for blockages. None found at the holes, but a healthy crop of barnacles were populating the surrounding areas of the drive. Started it up again and revved it a couple of times and the temp subsided to normal. Then a few minutes later the temp was up there again. I stopped. Turned off the engine. Restarted. And again, back to normal. This happened once or twice more during my time out but on these later occasions all I did was put the drive in neutral, rev the engine a couple of times, put it back in drive and the temp went back to normal saving me from having to get back up to plane from a dead stop. The question is, did I cause come damage, say, to the impellor from the impact on that large wave (this was a wake from a large ship that had passed about a 1/4 mile away in an otherwise flat and calm sea) or was it just coincidental that I may have picked up something that would cause random blocking/malfunctioning of the cooling system (would have to be pretty small to fit in the intake holes)? Thanks for your help. -Mike 1987 Sea Ray Sundancer 250 Repowered with a rebuild last year with 160 new hours on it. |
#2
|
|||
|
|||
Maybe a sticking thermostat. You have raw water cooling or a heat
exchanger? 160-170 is too high for raw water cooling. "MJT" wrote in message t... Went over a large wave yesterday and directly after that I noticed the water temp was over 200. Out of habit I scan this and the other essential gauges regularly when running. Up to that point the temp was the normal 160-170. I went to idle and then turned the engine off since this happened once before where I probably picked up a plastic bag wrapped around the water intake on the i/o. I raised the drive and felt around the intake holes searching for blockages. None found at the holes, but a healthy crop of barnacles were populating the surrounding areas of the drive. Started it up again and revved it a couple of times and the temp subsided to normal. Then a few minutes later the temp was up there again. I stopped. Turned off the engine. Restarted. And again, back to normal. This happened once or twice more during my time out but on these later occasions all I did was put the drive in neutral, rev the engine a couple of times, put it back in drive and the temp went back to normal saving me from having to get back up to plane from a dead stop. The question is, did I cause come damage, say, to the impellor from the impact on that large wave (this was a wake from a large ship that had passed about a 1/4 mile away in an otherwise flat and calm sea) or was it just coincidental that I may have picked up something that would cause random blocking/malfunctioning of the cooling system (would have to be pretty small to fit in the intake holes)? Thanks for your help. -Mike 1987 Sea Ray Sundancer 250 Repowered with a rebuild last year with 160 new hours on it. |
#3
|
|||
|
|||
How old in the impeller?
"MJT" wrote in message t... Went over a large wave yesterday and directly after that I noticed the water temp was over 200. Out of habit I scan this and the other essential gauges regularly when running. Up to that point the temp was the normal 160-170. I went to idle and then turned the engine off since this happened once before where I probably picked up a plastic bag wrapped around the water intake on the i/o. I raised the drive and felt around the intake holes searching for blockages. None found at the holes, but a healthy crop of barnacles were populating the surrounding areas of the drive. Started it up again and revved it a couple of times and the temp subsided to normal. Then a few minutes later the temp was up there again. I stopped. Turned off the engine. Restarted. And again, back to normal. This happened once or twice more during my time out but on these later occasions all I did was put the drive in neutral, rev the engine a couple of times, put it back in drive and the temp went back to normal saving me from having to get back up to plane from a dead stop. The question is, did I cause come damage, say, to the impellor from the impact on that large wave (this was a wake from a large ship that had passed about a 1/4 mile away in an otherwise flat and calm sea) or was it just coincidental that I may have picked up something that would cause random blocking/malfunctioning of the cooling system (would have to be pretty small to fit in the intake holes)? Thanks for your help. -Mike 1987 Sea Ray Sundancer 250 Repowered with a rebuild last year with 160 new hours on it. |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Operating Temp, Merc 5.7 Carb RWC | General | |||
Overheating problem update, 60 merc 4 stroke | General | |||
Merc 125 Bottom Carb dripping Gas | General | |||
Ad: $1,195 for Complete New Merc Alpha One Drives | General | |||
SOS Merc. Alpha Drive | Cruising |