Well, I replaced the thermostat in the cold motor. And I tried to find
"heat sticks" and nobody in the 3 auto part stores I went to knew what
they were. They did sell some laser things starting at about $100. But
I couldn't justify that for a one time deal. After replacing the
thermostat in the cold motor, it went up to about mid-way in the red
at idle. And my wife and I put our hands on the thermostat housing
after letting it idle in the red for about 5 minutes or so and counted
to between 3 and 4 seconds until we had to pull our hands off it. I
ran the "hot" motor and it ended up just slightly higher than mid-way
in the red and we could put our hands on the thermostat housing for
between 4 and 5 seconds. So, I was figuring that the guages just
weren't the right ones for this engine and that the engines were
running fine.

I then took them out on the water and both of them were idling in the
red (about mid-way). I then opened them up to about 2000 or so rpms
and they both cooled down to about mid-green. Then I think let them
idle again and the "hot" engine got to the top of the red again. So, I
shut that one off and ran the "cool" engine for a few minutes around
4000 rpms and I looked down and saw that one was up in the red. That
kind of surprised me because I had been thinking that at least the
"cold" motor would run well. The other day we had run that one for a
good 20 minutes at the same speed and it stayed in the green (that was
before we put the new thermostat in). Then we decided to head back -
and I kind of took turns with the motors trying to keep them as cool
as I could. Just before we got back we heard what I suspect was an
overheat alarm beep. So I shut them both off and tried to get anchored
- but we were in the way in the harbor by that time. When I turned the
key back on for the cold motor we just heard a steady alarm. So I
turned the key back on the for hot motor and puttered over - but it
was running "rough" by then I would say - it shut off once by itself -
and it didn't start right up that time.

So, I was thinking I must need have a semi-bad impeller in both motors
at this point. So, I just took apart the lower unit and pulled the
water pump on the cold motor. The impeller looked fine - no wear or
tear and still quite bendy. The inside of the water pump lining
doesn't have any scratches. So now I'm totally out of ideas. At this
point I'm believing the guages - since the overheat alarm sounded. Is
it possible I replaced the old thermostat that was stuck wide open in
the cold motor with a thermostat rated for a different temperature?
The new one looked the same as the old one (wierd plastic things -
kind of look like some kind of practice tips for archery (but too big
and plastic) with threads on the "shank" side that don't seem to
thread into anything). But I did notice the old one has 10LT stamped
on it and the new ones I got have G1C stamped on them.

Any ideas are GREATLY appreciated! Eldon

"Eldon Cutlip" wrote in message
om...

So, I was thinking I must need have a semi-bad impeller in both motors
at this point. So, I just took apart the lower unit and pulled the
water pump on the cold motor. The impeller looked fine - no wear or
tear and still quite bendy. The inside of the water pump lining
doesn't have any scratches. So now I'm totally out of ideas.

Replace the impellers. even if they look good they may not be. A few years
ago my dad was up in Canada fishing and the engine was running hot. Removed
the leg and "flipped" the impeller over. The engine ran fine the rest of the
trip. The impeller got changed ASAP!
Greg

"Greg O" wrote in message ...
"Eldon Cutlip" wrote in message
om...

So, I was thinking I must need have a semi-bad impeller in both motors
at this point. So, I just took apart the lower unit and pulled the
water pump on the cold motor. The impeller looked fine - no wear or
tear and still quite bendy. The inside of the water pump lining
doesn't have any scratches. So now I'm totally out of ideas.

Replace the impellers. even if they look good they may not be. A few years
ago my dad was up in Canada fishing and the engine was running hot. Removed
the leg and "flipped" the impeller over. The engine ran fine the rest of the
trip. The impeller got changed ASAP!
Greg

I replaced the water pump in the "cold" motor - or at least the one
that was cold originally After that, I had just enough time to
idle it for 5 or 10 minutes on the ears. It settled right at the mark
between the green and red. I didn't have a chance to get the other
engine's water pump done yet or to take the cold one out on the water.
But something still seems wrong even with the cold motor. I think I
will have to buy one of those laser temperature things. And I think
someone had mentioned that the oil to fuel mixture may be suspect.
Could running too lean cause the engines to run hotter? If so how do
I verify what the oil mixture is set to (these are the VRO Johnson
70's - 1986)? I had two of the local boat mechanics tell me the new
thermostats are the same as the ones I replaced.

So, I think the plan right now is replace the other water pump, get a
laser, and verify the oil mixture. I have no clue how to verify the
oil mixture but I guess I could just put oil in the fuel tank and see
if they stay cooler.

Thanks,
Eldon

On 18 May 2004 08:40:40 -0700, (Eldon Cutlip)
wrote:

"Greg O" wrote in message ...
"Eldon Cutlip" wrote in message
om...

So, I was thinking I must need have a semi-bad impeller in both motors
at this point. So, I just took apart the lower unit and pulled the
water pump on the cold motor. The impeller looked fine - no wear or
tear and still quite bendy. The inside of the water pump lining
doesn't have any scratches. So now I'm totally out of ideas.

Replace the impellers. even if they look good they may not be. A few years
ago my dad was up in Canada fishing and the engine was running hot. Removed
the leg and "flipped" the impeller over. The engine ran fine the rest of the
trip. The impeller got changed ASAP!
Greg

I replaced the water pump in the "cold" motor - or at least the one
that was cold originally After that, I had just enough time to
idle it for 5 or 10 minutes on the ears. It settled right at the mark
between the green and red. I didn't have a chance to get the other
engine's water pump done yet or to take the cold one out on the water.
But something still seems wrong even with the cold motor. I think I
will have to buy one of those laser temperature things. And I think
someone had mentioned that the oil to fuel mixture may be suspect.
Could running too lean cause the engines to run hotter? If so how do
I verify what the oil mixture is set to (these are the VRO Johnson
70's - 1986)? I had two of the local boat mechanics tell me the new
thermostats are the same as the ones I replaced.

So, I think the plan right now is replace the other water pump, get a
laser, and verify the oil mixture. I have no clue how to verify the
oil mixture but I guess I could just put oil in the fuel tank and see
if they stay cooler.

Thanks,
Eldon

Without verifying that both your gauges are accurate and reliable..
....... you could be farting against thunder!

Derek wrote in message . ..
On 18 May 2004 08:40:40 -0700, (Eldon Cutlip)
wrote:

"Greg O" wrote in message ...
"Eldon Cutlip" wrote in message
om...

So, I was thinking I must need have a semi-bad impeller in both motors
at this point. So, I just took apart the lower unit and pulled the
water pump on the cold motor. The impeller looked fine - no wear or
tear and still quite bendy. The inside of the water pump lining
doesn't have any scratches. So now I'm totally out of ideas.

Replace the impellers. even if they look good they may not be. A few years
ago my dad was up in Canada fishing and the engine was running hot. Removed
the leg and "flipped" the impeller over. The engine ran fine the rest of the
trip. The impeller got changed ASAP!
Greg

I replaced the water pump in the "cold" motor - or at least the one
that was cold originally After that, I had just enough time to
idle it for 5 or 10 minutes on the ears. It settled right at the mark
between the green and red. I didn't have a chance to get the other
engine's water pump done yet or to take the cold one out on the water.
But something still seems wrong even with the cold motor. I think I
will have to buy one of those laser temperature things. And I think
someone had mentioned that the oil to fuel mixture may be suspect.
Could running too lean cause the engines to run hotter? If so how do
I verify what the oil mixture is set to (these are the VRO Johnson
70's - 1986)? I had two of the local boat mechanics tell me the new
thermostats are the same as the ones I replaced.

So, I think the plan right now is replace the other water pump, get a
laser, and verify the oil mixture. I have no clue how to verify the
oil mixture but I guess I could just put oil in the fuel tank and see
if they stay cooler.

Thanks,
Eldon

Without verifying that both your gauges are accurate and reliable..
...... you could be farting against thunder!

Well, my thinking was that the laser temperature gun would tell me
exactly what temperature my engines are running at. I thought I could
then see what the guage was reading and "mentally calibrate" for my
guages. How else can I verify my guages are accurate and reliable?

Eldon

On 19 May 2004 08:40:19 -0700, (Eldon Cutlip)
wrote:

Derek wrote in message . ..
On 18 May 2004 08:40:40 -0700, (Eldon Cutlip)
wrote:

"Greg O" wrote in message ...
"Eldon Cutlip" wrote in message
om...

So, I was thinking I must need have a semi-bad impeller in both motors
at this point. So, I just took apart the lower unit and pulled the
water pump on the cold motor. The impeller looked fine - no wear or
tear and still quite bendy. The inside of the water pump lining
doesn't have any scratches. So now I'm totally out of ideas.

Replace the impellers. even if they look good they may not be. A few years
ago my dad was up in Canada fishing and the engine was running hot. Removed
the leg and "flipped" the impeller over. The engine ran fine the rest of the
trip. The impeller got changed ASAP!
Greg

I replaced the water pump in the "cold" motor - or at least the one
that was cold originally After that, I had just enough time to
idle it for 5 or 10 minutes on the ears. It settled right at the mark
between the green and red. I didn't have a chance to get the other
engine's water pump done yet or to take the cold one out on the water.
But something still seems wrong even with the cold motor. I think I
will have to buy one of those laser temperature things. And I think
someone had mentioned that the oil to fuel mixture may be suspect.
Could running too lean cause the engines to run hotter? If so how do
I verify what the oil mixture is set to (these are the VRO Johnson
70's - 1986)? I had two of the local boat mechanics tell me the new
thermostats are the same as the ones I replaced.

So, I think the plan right now is replace the other water pump, get a
laser, and verify the oil mixture. I have no clue how to verify the
oil mixture but I guess I could just put oil in the fuel tank and see
if they stay cooler.

Thanks,
Eldon

Without verifying that both your gauges are accurate and reliable..
...... you could be farting against thunder!

Well, my thinking was that the laser temperature gun would tell me
exactly what temperature my engines are running at. I thought I could
then see what the guage was reading and "mentally calibrate" for my
guages. How else can I verify my guages are accurate and reliable?

Eldon


Wal-Mart sells mechanical temp gauges (made by Equius) for around $10.
They come with a good selection of fittings and mine is very accurate.
You should be able to install a "T" piece fitting that will accept
both your electric gauge and the mechanical one simultaniously. Try
vairying the the engine conditions (NEVER rev a motor above 2000
r.p.m. in neutral). The two gauges should follow each other closely.
Now, test the other motor. All done for around $15.

Just be careful not to kink the temp gauge line, it's filled with
liquid (alcohol, I think). Ideally, this test should be performed
under normal operating conditions.

Another method, but do this at your own risk, is to ground out the
wire to the sender unit via a selection of various resistors. For
example, if a 500 Ohm resistor takes the gauge to half, and a 200 Ohm
takes it to one quarter, it MUST do the same on the other gauge. Next,
remove the sender units and put them in a pot of warm water for a bit.
Using a digital multimeter, record the Ohms readings of both. Heat the
water a little more and repeat, all the way up to near boiling. I'm
guessing the readings should be within about 5% of each other.
Remember to make the readings quickly, for accuracy. Problem is, if
they're way out, which one is faulty???? This is why I preffer a
mechanical gauge over an electric gauge whenever possible, even for
Volts (joke!). Unfortunately, the pivoting and steering system of a
boat does not lend itself to these gauges, unless they're mounted on
the motor directly (another temporary option).

Okay, since I have a few minutes, and it were my boat, here's what I'd
do (at your own risk of course)

1) Replace the other impellor (water pump).
2) Ensure that all the seals between the pump and the head are good.
You could even be losing water pressure/volume from a leaking
seal or joint somewhere along that pipe (been there, done that).
3) Remove both thermostats, and leave housings open. BRIEFLY run
engines at idle and a little above. Both "fountains" should be
similar in volume and pressure (use drums, not ear muffs, for a
true simulation.)
4) Verify that both thermostats are working similarly, by using the
pot on a stove method.
5) Verify that both temperature gauges are accurate/reliable.
(also check for and clean any corrosion on any terminals).

Basically, you start at the beginning (pump) and logically eliminate
any discrepencies between the 2 motors.

I would also suggest getting a manual for your motor. They are
invaluable.

Good Luck.

Wal-Mart sells mechanical temp gauges (made by Equius) for around $10.
They come with a good selection of fittings and mine is very accurate.
You should be able to install a "T" piece fitting that will accept
both your electric gauge and the mechanical one simultaniously. Try
vairying the the engine conditions (NEVER rev a motor above 2000
r.p.m. in neutral). The two gauges should follow each other closely.
Now, test the other motor. All done for around $15.

Just be careful not to kink the temp gauge line, it's filled with
liquid (alcohol, I think). Ideally, this test should be performed
under normal operating conditions.

Another method, but do this at your own risk, is to ground out the
wire to the sender unit via a selection of various resistors. For
example, if a 500 Ohm resistor takes the gauge to half, and a 200 Ohm
takes it to one quarter, it MUST do the same on the other gauge. Next,
remove the sender units and put them in a pot of warm water for a bit.
Using a digital multimeter, record the Ohms readings of both. Heat the
water a little more and repeat, all the way up to near boiling. I'm
guessing the readings should be within about 5% of each other.
Remember to make the readings quickly, for accuracy. Problem is, if
they're way out, which one is faulty???? This is why I preffer a
mechanical gauge over an electric gauge whenever possible, even for
Volts (joke!). Unfortunately, the pivoting and steering system of a
boat does not lend itself to these gauges, unless they're mounted on
the motor directly (another temporary option).

Okay, since I have a few minutes, and it were my boat, here's what I'd
do (at your own risk of course)

1) Replace the other impellor (water pump).
2) Ensure that all the seals between the pump and the head are good.
You could even be losing water pressure/volume from a leaking
seal or joint somewhere along that pipe (been there, done that).
3) Remove both thermostats, and leave housings open. BRIEFLY run
engines at idle and a little above. Both "fountains" should be
similar in volume and pressure (use drums, not ear muffs, for a
true simulation.)
4) Verify that both thermostats are working similarly, by using the
pot on a stove method.
5) Verify that both temperature gauges are accurate/reliable.
(also check for and clean any corrosion on any terminals).

Basically, you start at the beginning (pump) and logically eliminate
any discrepencies between the 2 motors.

I would also suggest getting a manual for your motor. They are
invaluable.

Good Luck.

I really appreciate your time on this! I just got the manual via UPS
and my wife ordered one of the temperature laser gun things. And I
will be starting through your suggestions starting with the water pump
in the "hot" engine when I get back home this weekend.

Thanks!
Eldon

"Derek" wrote



Wal-Mart sells mechanical temp gauges (made by Equius) for around $10.
They come with a good selection of fittings and mine is very accurate.

Which department at Walmart did you find it in?

Cam

On Thu, 20 May 2004 08:37:22 -0800, "Camilo"
wrote:


"Derek" wrote



Wal-Mart sells mechanical temp gauges (made by Equius) for around $10.
They come with a good selection of fittings and mine is very accurate.

Which department at Walmart did you find it in?

Cam


The Auto section, where they keep all the oil, Volt, Amp etc. gauges
for cars. They're pretty common at auto accesorie stores. I've seen
them at Canadian Tire here in Canada too.

"Eldon Cutlip" wrote in message
om...


I really appreciate your time on this! I just got the manual via UPS
and my wife ordered one of the temperature laser gun things. And I
will be starting through your suggestions starting with the water pump
in the "hot" engine when I get back home this weekend.

Thanks!
Eldon


Be sure you install the factory water pump kit #432995 which contains
everything you need to replace it plus items to upgrade your cooling system.
You will get a different thermostat spring and a plastic water tell-tale
fitting that get relocated to the top of the exhaust housing to purge
trapped air in the system.

Remember that your temperature gauges are not precision instruments and that
the sender is only reading "skin temperature" of the motor, which may be
higher or lower than the internal water temp of the engine.

Keep us posted

Bill Grannis
service manager