Mr Don please? UPDATE,Thanks Don!

[Gary H NC]

On this freshwater cooled Merc i posted about in the other thread.

I pulled the end covers off the heat exchanger....no water.
I got looking under the engine and noticed a large through hull fitting with a ball valve handle.
This is plumbed directly to the engine mounted raw water pump.Then the other hose from the raw water pump goes to the PS cooler then up to the heat exchanger.

I pulled a drain plug on the bottom of one of the manifolds...green AF.
I then pulled the small brass plugs on the sides of the risers and got just a little fresh water..

Confused as what else to drain...

I called the owner and he said the guy he bought it from told him it was easy to winterize but thats all he said.

Also this guy has been running it on muffs so my bet is the impeller in the pump is toast.

I can post engine serial if needed..

 

[Don S]

Re: Mr Don please?

Re: Mr Don please?

Ok, with the engine mounted raw water pump, the impeller may be a bit week and will allow the system to drain out if there are no high spots in the hoses. The reason for the inboard mounted pump is the outdrive pump is not enough when the manifolds are cooled in the closed cooling loop.

Oops, clicked the post button before I was done.
The risers, the heat exchanger, power steering cooler and the raw water pump are all you need to drain. Sounds like the way it's setup it's self draining.
The impeller in the drive are usually always dead when setup like that. They do circulate water through the drive which helps cool the drive, but if the owner doesn't have a problem with burned gear lube, it's probably not a problem.

You may want this But it probably won't help much.

 

[Gary H NC]

Re: Mr Don please?

Re: Mr Don please?

Thanks Don!

The hose from the engine mounted raw water pump turns straight down to the through hull fitting so the raw water pump must be self draining.

Looks like all i need now is to get the hose from the PS cooler off and drain it.
I can hardly get my hand down there...should be fun.

It looks like the water pick up hose from the drive that is next to the bellows
is not connected to anything.

I did find a diagram in Manual #17 that has the same system..

Thanks for the help!

Oh,This thing is a 96 model according to the hull ID...

 

[Don S]

Re: Mr Don please?

Re: Mr Don please?

It looks like the water pick up hose from the drive that is next to the bellows
is not connected to anything.

They are supposed to be cut off near the bellhousing but still allows the pump to pump.

Looks like all i need now is to get the hose from the PS cooler off and drain it.
I can hardly get my hand down there...should be fun.

Yeah, Merc had to find a place that was inaccessable, couldn't put it up high and at an angle like others do, then they are self draining, or very easy to drain.

 

[Gary H NC]

Re: Mr Don please?

Re: Mr Don please?

Crawling in there now...Thanks Don!!!

Dang tight area to work!

 

[Gary H NC]

Re: Mr Don please? UPDATE,Thanks Don!

Could not get the PS cooler hose off after trying every position possible...ugh!

I unhooked the other end of the hose at the heat exchanger and poured about a gallon of RV antifreeze down the cooler until it ran out of the through hull fitting for the raw water pump..
Hopefully this will be ok...

Did not want to destroy the cooler trying to get the hose off.....

 

[HT32BSX115]

Re: Mr Don please? UPDATE,Thanks Don!

This is why I don't even attempt to remove hoses in there. It's almost impossible to get to everything without pulling the back bench seat and standing on my head!!!

I just suck up some 50/50 AF mix (after priming it) and let the discharge drain (at the transom/gimbal exhaust exit point) into the same pan I'm sucking it out of.

I let it circulate until it starts getting hot. (for everyone else.....this is a closed cooled engine and manifolds.... DON'T do this on a raw water cooled engine unless you remove the thermostat first or your block may not get enough AF concentration to prevent freezing and even then it may still not get enough......)


After I'm done, the whole raw water side has AF mix in the low spots.

I don't have to crawl anywhere!!


Regards,


Rick

 

[Gary H NC]

Re: Mr Don please? UPDATE,Thanks Don!

I hear ya! With the way this boat has the water pickup under the hull i would have to have some type of rubber suction cup to hook to it.About the size of a toilet plunger...

 

[dubs283]

Re: Mr Don please? UPDATE,Thanks Don!

i would have to have some type of rubber suction cup to hook to it.About the size of a toilet plunger

its called a "fake a lake"

google it and you will see that it looks just like your toilet plunger

there are other styles without the stick - they have a hook that connects to the pickup, its basically one half of a bravo muff with the wire bent to hook to the pickup

 

[HT32BSX115]

Re: Mr Don please? UPDATE,Thanks Don!

I hear ya! With the way this boat has the water pickup under the hull i would have to have some type of rubber suction cup to hook to it.About the size of a toilet plunger...

Well, that would indeed be difficult!

You could use a valve to close(seacock) and a T-fitting inside to connect to the water pick up hose to your container.....


The bravo raw water pump doesn't prime well if it has to pull water up from below the drive. (you need to have liquid up against the impeller)




When the boat is sitting in the water the raw water pump is essentially at or slightly below the water line.......so there's basically a slight "head" pressure at the pump. It doesn't have to be primed that way of course.


If you're trying to prime out of the water you have to use a hose that's already filled with water/af mix and the siphon already "started".

I have the container sitting on the swimstep and the hose primed and a small plastic valve at the "muffs" closed.

I have someone start the engine as I open the valve.

Once the engine is started, I can put the container under the transom to catch the discharge and keep the container full. (I usually don't spill much at all....)

Then it just circulates.....

 

[Gary H NC]

Re: Mr Don please? UPDATE,Thanks Don!

Thanks for the info! Everything is drained now except the raw water pump and PS cooler but they are full of AF so it should be good to go.

The guy that owns the boat has been running it on regular muffs so you know the raw water pump is shot.
I tried to explain everything to him but all he says is that it never ran hot on the muffs..

He also said it keeps burping antifreeze out of the closed side into the over flow bottle.
I bet the closed side is getting hot because the raw water pump is toast and the heat exchanger is not staying cool..

He does not want to spend the money for me to pull it apart and inspect it...

 

[Don S]

Re: Mr Don please? UPDATE,Thanks Don!

He also said it keeps burping antifreeze out of the closed side into the over flow bottle.
I bet the closed side is getting hot because the raw water pump is toast and the heat exchanger is not staying cool..

If he keeps filling the expansion tank right to the top, then it will keep burping, it's making room for expansion.
The impeller in the drive does NOTHING for the engine cooling. However, that engine driven pump should be replaced every other year, they don't last that long.
Even when running properly, the heat exchanger will feel hot in the middle of it. Just like a radiator feels hot at the top, so does a heat exchanger, you are feeling the AF side, and it's running 170 to 180? which you can't keep your hand on comfortably for over 5 seconds.

 

[Gary H NC]

Re: Mr Don please? UPDATE,Thanks Don!

Thanks Don,
I'm going to try to talking him into replacing the impeller in the engine driven pump.He has been running it dry all summer in the driveway..