I've got a 350 Mercruiser inboard with a closed cooling system.
We have such high municipal water pressure that the garden hose blew out the
gasket of my raw water flow sensor.
Next time I'll install a shut off valve near the end of the garden hose so I
can stop the water flow when the engine isn't running.
Anyone seen this problem? It also made one of the raw water filter
connections leak. Double clamped too.
I don't think you ever get that much pressure on the cooling system with
normal use.

Also, I used 1 part anti freeze to 3 parts water for the closed cooling
system. This was based on advice from a guy at Holt heat exchangers. I
trust him completely. Any opinons on this anti freeze ratio?

Other wise it started right up as soon as I remembered to open the fuel shut
off valve....

You don't need, in fact you shouldn't open the valve all the way open when
running it from a hose.

--
Bill
Chesapeake, Va


"Jim and Becky" wrote in message
...
I've got a 350 Mercruiser inboard with a closed cooling system.
We have such high municipal water pressure that the garden hose blew out
the
gasket of my raw water flow sensor.
Next time I'll install a shut off valve near the end of the garden hose so
I
can stop the water flow when the engine isn't running.
Anyone seen this problem? It also made one of the raw water filter
connections leak. Double clamped too.
I don't think you ever get that much pressure on the cooling system with
normal use.

Also, I used 1 part anti freeze to 3 parts water for the closed cooling
system. This was based on advice from a guy at Holt heat exchangers. I
trust him completely. Any opinons on this anti freeze ratio?

Other wise it started right up as soon as I remembered to open the fuel
shut
off valve....

"Jim and Becky" wrote in message
news:be2dnaj3G74bKAjdRVn-

We have such high municipal water pressure that the garden hose blew out
the
gasket of my raw water flow sensor.
Next time I'll install a shut off valve near the end of the garden hose so
I

Try installing an in-line pressure regulator, available at any boat store
for a few bucks. It regulates to about 35-40#, iirc. Also pick up an
in-line shutoff, a buck or two, as used on yard hoses.

"WRH" wrote
You don't need, in fact you shouldn't open the
valve all the way open when running it from a hose.

Which brings up the question, "how much is enough?" I test ran my boat a
week ago and noticed the temp was a few degrees higher than expected. I
opened the valve a little more and the temp gauge settled down to it's
accustomed place. (I use a cheesy little plastic in-line ball valve between
the end of the hose and the earmuff to fine tune.)

"Jim and Becky" wrote in message
...
I've got a 350 Mercruiser inboard with a closed cooling system.
We have such high municipal water pressure that the garden hose blew out
the
gasket of my raw water flow sensor.


How did you have the hose connected to the motor?

The "ear muffs" that I use on my outboard and the "fake lake" I use on my
outboard simply leak with any significant pressure.

If your adapter clamps on in such a way that you could develop any
significant pressure then I would recommend making your own pressure
regulator. A very simple way would be to put a Tee right at the clamp
fitting. Attach a length of hose to the third leg of the tee and run it a
few feet above the water pump level. Excess water will flow out the free
end of the hose


Rod

I disconnect the 1" hose at the seacock. I customized a length of garden
hose by clamping on a 5/8" - 1" connector at the end. I just shove the 1"
end into the intake hose and clamp it. No messy water spraying anywhere.
Except out of the flow sensor. Yes a double valve T is a good idea, with the
water running out the other side when the engine isn't running. I'd rather
waste a few gallons of water than back up the entire 150' of hose I need. It
consists of every hose and piece of hose I own. I get that Sanford and son
feeling...

"Rod McInnis" wrote in message
...

"Jim and Becky" wrote in message
...
I've got a 350 Mercruiser inboard with a closed cooling system.
We have such high municipal water pressure that the garden hose blew out
the
gasket of my raw water flow sensor.


How did you have the hose connected to the motor?

The "ear muffs" that I use on my outboard and the "fake lake" I use on my
outboard simply leak with any significant pressure.

If your adapter clamps on in such a way that you could develop any
significant pressure then I would recommend making your own pressure
regulator. A very simple way would be to put a Tee right at the clamp
fitting. Attach a length of hose to the third leg of the tee and run it a
few feet above the water pump level. Excess water will flow out the free
end of the hose


Rod

"Jim and Becky" wrote in message
...



I disconnect the 1" hose at the seacock.


If you do this often there is a real easy modification you can make that
will make this job a LOT easier.

Cut the hose from the seacock in some easy to get to place, the closer to
the water pump the better. Install a Tee in the hose. Install a valve on
the third leg of the Tee. Install a female hose fitting on the open side of
the valve.

For normal operation the valve is closed and the raw water pump draws water
from the lake just like always.

For trailer operation, you open the valve and attach the water hose. When
you turn the hose on, the water flows out the hose then out the seacock on
the bottom of the boat (do NOT close the seacock!). When you start the
motor, it will draw the water up from the Tee.

Just be sure to close the valve when you are done with the hose.


Rod

Rod McInnis wrote:

:If you do this often there is a real easy modification you can make that
:will make this job a LOT easier.
:
:Cut the hose from the seacock in some easy to get to place, the closer to
:the water pump the better. Install a Tee in the hose. Install a valve on
:the third leg of the Tee. Install a female hose fitting on the open side of
:the valve.
:
:For normal operation the valve is closed and the raw water pump draws water
:from the lake just like always.
:
:For trailer operation, you open the valve and attach the water hose. When
:you turn the hose on, the water flows out the hose then out the seacock on
:the bottom of the boat (do NOT close the seacock!). When you start the
:motor, it will draw the water up from the Tee.
:
:Just be sure to close the valve when you are done with the hose.

I've thought about installing this setup on my boat (130hp Volvo I/O),
but I was concerned that, when using the garden hose for water, the
water would not be sucked up by the engine mounted raw water pump and
instead just go out the hose that normally carries water from the
outdrive's water intakes to the water pump. Am I wrong about this?

Now what I do is attach the garden hose to a 4' length of clear hose
that has female garden hose fitting on one end and nothing on the
other. I then remove the hose from the intake side of the water pump
and replace it with the naked end of the clear hose that is attached to
the garden hose. Before I attach it though, I turn the water on at the
main garden hose valve and make a mental note of how far I need to turn
the handle in order to get a fairly low pressure stream of water coming
out the end of the hose I'll be attaching to the water pump. It sounds
complicated, but it's actually very simple!

"Bob" wrote in message
...


I've thought about installing this setup on my boat (130hp Volvo I/O),
but I was concerned that, when using the garden hose for water, the
water would not be sucked up by the engine mounted raw water pump and
instead just go out the hose that normally carries water from the
outdrive's water intakes to the water pump. Am I wrong about this?



In normal operation, the water pump has to suck water up from the bottom of
the boat through that very same hose. There is a possibility that IF the
hose diameter was very large and the water stream from the garden hose
rather small then the trickle of water from the garden hose could fall down
the water inlet hose while air traveled up and thus the pump wouldn't suck
water.

On my boat, a tournament ski boat with a 351 cu-in V8 engine, this was never
a problem. I would turn the hose on and get a good stream out the bottom of
the boat. When the engine started, it would suck ALL of the water up, none
would go out the bottom.

You can tell right away if it is working or not. If the exhaust is coming
out dry then you aren't sucking water. If the exhaust has a lot of water in
it then things are fine.


rod

I used to do it that was but kept getting water everywhere. I have an
inboard and everything is just harder to get to than an I/O.
I won't put a permanent T in the line as I only need to use it twice a year:
Spring and Fall.


I've thought about installing this setup on my boat (130hp Volvo I/O),
but I was concerned that, when using the garden hose for water, the
water would not be sucked up by the engine mounted raw water pump and
instead just go out the hose that normally carries water from the
outdrive's water intakes to the water pump. Am I wrong about this?

Now what I do is attach the garden hose to a 4' length of clear hose
that has female garden hose fitting on one end and nothing on the
other. I then remove the hose from the intake side of the water pump
and replace it with the naked end of the clear hose that is attached to
the garden hose. Before I attach it though, I turn the water on at the
main garden hose valve and make a mental note of how far I need to turn
the handle in order to get a fairly low pressure stream of water coming
out the end of the hose I'll be attaching to the water pump. It sounds
complicated, but it's actually very simple!