Overheating problems - getting more bizarre every day....
 

If you have been reading here for the last 2 weeks, you may have come
across my 2 or 3 posts about my boat's overheating problems:
essentially, boat overheats for 3 to 5 minutes (at startup) and then
temp needle drops back to normal and everything is fine. It is a raw
water cooling system and the boat runs in sal****er. Because of
various tests and checks (including replacing the thermostat), I am
pretty sure it is not the stern drive pump/impeller, thermostat or
clogged hoses.

Friday, we decided to go to my (boat-access only) cabin. The boat
started beautifully, I put the boat in gear and away we went: no
problem whatesoever, the temp never went passed 150F (stayed pretty
steady at 130F). 25 minutes minutes later we arrived at the cabin and
I thought that perhaps my overheating problems were a thing of the
past!

NOT SO... After a celebratory beer, we decided to go drop the prawn
trap. Our preferred spot is only 2-3 minutes from our cabin's dock.
Well, by the time we got to the spot, the temp had creeped up to 220F!
The overheating problem was back! But that is not all! Now the boat
would not even restart! After numerous attempts, we had to be towed
back to our dock. Because the non-starting problem happened at the
same time as the overheating problem, we naturally concluded that they
must be related. But the next day, when the boat was cold, I tried to
start the boat (fully expecting that it would) but no luck! You can
tell that the battery is fine (trim and bilge works, engine tries to
turn over) but something else is preventing the engine from starting.
As far as I know, the cooling system should have nothing to do with
starting the motor (especially if the boat has already cooled down) so
I am now thinking that this is a totally new, unrelated problem.

My friend thinks the starter might be broken (he said he had a broken
starter on his Jeep and it acted/sounded just like the boat).

Anyway, after dropping the prawn trap on Friday afternoon, I never
managed to restart the boat and we had to be towed back to the marina
(big thanks to my neighbour at the cabin) on Sunday.

What do you boaters think? Related or unrelated problem? Likely that
it is the starter or not? How can the boat perform flawlessly (at 130F
with good oil pressure, etc.) for 25 minutes and then overheats to 225F
next time I use it!? How can an overheating problem be so random?

Anyway, this is now all beyond my level of comprehension and I am
trying very hard to book a mechanic. The problem is, even tough I live
in a coastal area (Vancouver, BC) where one would think there is a
large supply of boat mechanics, finding an available/willing mechanic
around here seems to be harder than finding Bin Ladden!

Anyway, as usual would be interested in your feedback and comments
about this very weird situation... Cheers! Andre

Please remove all of the spark plugs and attempt to turn the engine over
with the starter. Watch for water coming out of the spark plug holes, if the
engine turns over.
JIMinFL
"Melandre" wrote in message
oups.com...
If you have been reading here for the last 2 weeks, you may have come
across my 2 or 3 posts about my boat's overheating problems:
essentially, boat overheats for 3 to 5 minutes (at startup) and then
temp needle drops back to normal and everything is fine. It is a raw
water cooling system and the boat runs in sal****er. Because of
various tests and checks (including replacing the thermostat), I am
pretty sure it is not the stern drive pump/impeller, thermostat or
clogged hoses.

Friday, we decided to go to my (boat-access only) cabin. The boat
started beautifully, I put the boat in gear and away we went: no
problem whatesoever, the temp never went passed 150F (stayed pretty
steady at 130F). 25 minutes minutes later we arrived at the cabin and
I thought that perhaps my overheating problems were a thing of the
past!

NOT SO... After a celebratory beer, we decided to go drop the prawn
trap. Our preferred spot is only 2-3 minutes from our cabin's dock.
Well, by the time we got to the spot, the temp had creeped up to 220F!
The overheating problem was back! But that is not all! Now the boat
would not even restart! After numerous attempts, we had to be towed
back to our dock. Because the non-starting problem happened at the
same time as the overheating problem, we naturally concluded that they
must be related. But the next day, when the boat was cold, I tried to
start the boat (fully expecting that it would) but no luck! You can
tell that the battery is fine (trim and bilge works, engine tries to
turn over) but something else is preventing the engine from starting.
As far as I know, the cooling system should have nothing to do with
starting the motor (especially if the boat has already cooled down) so
I am now thinking that this is a totally new, unrelated problem.

My friend thinks the starter might be broken (he said he had a broken
starter on his Jeep and it acted/sounded just like the boat).

Anyway, after dropping the prawn trap on Friday afternoon, I never
managed to restart the boat and we had to be towed back to the marina
(big thanks to my neighbour at the cabin) on Sunday.

What do you boaters think? Related or unrelated problem? Likely that
it is the starter or not? How can the boat perform flawlessly (at 130F
with good oil pressure, etc.) for 25 minutes and then overheats to 225F
next time I use it!? How can an overheating problem be so random?

Anyway, this is now all beyond my level of comprehension and I am
trying very hard to book a mechanic. The problem is, even tough I live
in a coastal area (Vancouver, BC) where one would think there is a
large supply of boat mechanics, finding an available/willing mechanic
around here seems to be harder than finding Bin Ladden!

Anyway, as usual would be interested in your feedback and comments
about this very weird situation... Cheers! Andre

"Melandre" wrote in message
oups.com...
If you have been reading here for the last 2 weeks, you may have come
across my 2 or 3 posts about my boat's overheating problems:
essentially, boat overheats for 3 to 5 minutes (at startup) and then
temp needle drops back to normal and everything is fine. It is a raw
water cooling system and the boat runs in sal****er. Because of
various tests and checks (including replacing the thermostat), I am
pretty sure it is not the stern drive pump/impeller, thermostat or
clogged hoses.

Friday, we decided to go to my (boat-access only) cabin. The boat
started beautifully, I put the boat in gear and away we went: no
problem whatesoever, the temp never went passed 150F (stayed pretty
steady at 130F). 25 minutes minutes later we arrived at the cabin and
I thought that perhaps my overheating problems were a thing of the
past!

NOT SO... After a celebratory beer, we decided to go drop the prawn
trap. Our preferred spot is only 2-3 minutes from our cabin's dock.
Well, by the time we got to the spot, the temp had creeped up to 220F!
The overheating problem was back! But that is not all! Now the boat
would not even restart! After numerous attempts, we had to be towed
back to our dock. Because the non-starting problem happened at the
same time as the overheating problem, we naturally concluded that they
must be related. But the next day, when the boat was cold, I tried to
start the boat (fully expecting that it would) but no luck! You can
tell that the battery is fine (trim and bilge works, engine tries to
turn over) but something else is preventing the engine from starting.
As far as I know, the cooling system should have nothing to do with
starting the motor (especially if the boat has already cooled down) so
I am now thinking that this is a totally new, unrelated problem.

My friend thinks the starter might be broken (he said he had a broken
starter on his Jeep and it acted/sounded just like the boat).

Anyway, after dropping the prawn trap on Friday afternoon, I never
managed to restart the boat and we had to be towed back to the marina
(big thanks to my neighbour at the cabin) on Sunday.

What do you boaters think? Related or unrelated problem? Likely that
it is the starter or not? How can the boat perform flawlessly (at 130F
with good oil pressure, etc.) for 25 minutes and then overheats to 225F
next time I use it!? How can an overheating problem be so random?

Anyway, this is now all beyond my level of comprehension and I am
trying very hard to book a mechanic. The problem is, even tough I live
in a coastal area (Vancouver, BC) where one would think there is a
large supply of boat mechanics, finding an available/willing mechanic
around here seems to be harder than finding Bin Ladden!

Anyway, as usual would be interested in your feedback and comments
about this very weird situation... Cheers! Andre


Sounds like a cracked block... had a friend with a similar problem after a
local marina failed to correctly winterize one of his engines in his 37 foot
searay...

I am obviously not ruling out anything at this point but why do you
jump to the conclusion that it is a cracked block? My (poor)
understanding is that a starting system is composed of many parts
(battery, starter, ignition switch, alternator, solanoids, etc.) so
wouldn't it be more likely to be something related to the above parts?
I am having a hard time to believe that the motor APPEARED to be
working perfectly for 25 minutes going to the cabin and, following a
restart, I would end up with a cracked block 3 minutes later while
going to drop a prawn trap... Just my unprofessional thought....
Andre

Does the engine crank over, do you see the belt pulleys turning while
cranking? If not pull the spark plugs and try to crank it over.

"Melandre" wrote in message
ups.com...
I am obviously not ruling out anything at this point but why do you
jump to the conclusion that it is a cracked block? My (poor)
understanding is that a starting system is composed of many parts
(battery, starter, ignition switch, alternator, solanoids, etc.) so
wouldn't it be more likely to be something related to the above parts?
I am having a hard time to believe that the motor APPEARED to be
working perfectly for 25 minutes going to the cabin and, following a
restart, I would end up with a cracked block 3 minutes later while
going to drop a prawn trap... Just my unprofessional thought....
Andre

Dan J.S. wrote:
"Melandre" wrote in message
oups.com...

If you have been reading here for the last 2 weeks, you may have come
across my 2 or 3 posts about my boat's overheating problems:
essentially, boat overheats for 3 to 5 minutes (at startup) and then
temp needle drops back to normal and everything is fine. It is a raw
water cooling system and the boat runs in sal****er. Because of
various tests and checks (including replacing the thermostat), I am
pretty sure it is not the stern drive pump/impeller, thermostat or
clogged hoses.

Friday, we decided to go to my (boat-access only) cabin. The boat
started beautifully, I put the boat in gear and away we went: no
problem whatesoever, the temp never went passed 150F (stayed pretty
steady at 130F). 25 minutes minutes later we arrived at the cabin and
I thought that perhaps my overheating problems were a thing of the
past!

NOT SO... After a celebratory beer, we decided to go drop the prawn
trap. Our preferred spot is only 2-3 minutes from our cabin's dock.
Well, by the time we got to the spot, the temp had creeped up to 220F!
The overheating problem was back! But that is not all! Now the boat
would not even restart! After numerous attempts, we had to be towed
back to our dock. Because the non-starting problem happened at the
same time as the overheating problem, we naturally concluded that they
must be related. But the next day, when the boat was cold, I tried to
start the boat (fully expecting that it would) but no luck! You can
tell that the battery is fine (trim and bilge works, engine tries to
turn over) but something else is preventing the engine from starting.
As far as I know, the cooling system should have nothing to do with
starting the motor (especially if the boat has already cooled down) so
I am now thinking that this is a totally new, unrelated problem.

My friend thinks the starter might be broken (he said he had a broken
starter on his Jeep and it acted/sounded just like the boat).

Anyway, after dropping the prawn trap on Friday afternoon, I never
managed to restart the boat and we had to be towed back to the marina
(big thanks to my neighbour at the cabin) on Sunday.

What do you boaters think? Related or unrelated problem? Likely that
it is the starter or not? How can the boat perform flawlessly (at 130F
with good oil pressure, etc.) for 25 minutes and then overheats to 225F
next time I use it!? How can an overheating problem be so random?

Anyway, this is now all beyond my level of comprehension and I am
trying very hard to book a mechanic. The problem is, even tough I live
in a coastal area (Vancouver, BC) where one would think there is a
large supply of boat mechanics, finding an available/willing mechanic
around here seems to be harder than finding Bin Ladden!

Anyway, as usual would be interested in your feedback and comments
about this very weird situation... Cheers! Andre



Sounds like a cracked block... had a friend with a similar problem after a
local marina failed to correctly winterize one of his engines in his 37 foot
searay...



A little quick off the mark, perhaps?

You may have several problems, one or a combination of which has
seemingly blown up your engine.

You say "Tries to turn over" does it turn over or not? If it spins
over like normal, then you do not have a flat battery. Just because
a fan works does not mean the battery is charged enough. Try a fresh
battery for a boost, or try checking Specific Gravity of the
electrolyte liquid in each cell of your battery, though good SG does
not neccessarily mean all is well. A loose connection or resistive
connection may be at fault, perhaps at the battery switch, starter
solenoid, or main starter connection. (The heavy wire)

If the boost works out OK, find out why the old one is flat.
Something left on? Bad alternator? Charge it and check it again
after a day or two. Does it hold a charge? It could just be old
and tired.

Overheating immediately on startup then cooling normally almost
always means a balky thermostat, old or brand new, or even an
improper thermostat gasket installation, which you may have
replicated while changing a good thermostat. Boil it in water to
see when it opens. It could also mean a bad pump impeller. Does it
move lots of water, or not? You should be able to tell by looking at
the exhaust, or the hoses that feed hot engine cooling water to the
wet section of your exhaust. Just pop off the hose for a second,
once you get it to spin and start. Stop the engine and then reattach
thos hose.

If you overheat your engine enough, you will eventually ruin the
head gasket, which can prevent starting when hot but allow some
running while cool, off and on for a while, until you lose enough
compression that it won't start at all. It can also warp a head so a
new gasket will fail immediately. A machine shop will test and plane
the head, restoring its ability to seal the combustion chamber.

A compression test should lead you toward that reason.

an overheated engine may break a piston ring, but if only one is
gone, you will get a missfire on that cylinder, and probably oil on
the air filter.

If you want your bomb fixed properly, hire a bomb tech.

Terry K

Well, I just drove the boat this morning to the boat hospital :-(
This marine repair shop is apparently quite good so I am hopeful they
will find and fix the problem(s). I am looking forward to having a
well working boat but not looking forward to seeing the repair bill.
OUCH! Will let the group know what the problem was and thank you for
the great feedback on my overheating/non-starting problems!


Andre