Merc 470 convert to open system ? Why Not

[JustJason]

Re: Merc 470 convert to open system ? Why Not

open deck motor....

 

[Bob_VT]

Re: Merc 470 convert to open system ? Why Not

I am also a previous 3.7 470 owner.

People are dumping that engine every season and being on a budget..... there are tons of parts ....... used parts that is. If you need a heat exchanger they are out there cheap. Your sources will be ebay craigslist and the BEST source is a boat yard. I will bet there is a 470 laying in a scapped boat.

The heat exchanger is easy. Going to a one wire alternator is smart. Keep a very close eye on the risers..... when they crack you have a problem with hydraulic lock up.

It's just easier and actually cheaper to stay with the designed system. There are sources on the internet that also say the 3.0L is a good drop in for the 3.7L (actually it is the easyest conversion). Trust me.... if Mercruiser could have kept the 470 alive by converting it...... they would have designed a conversion for sale.


Keep an eye peeled for a junked boat

 

[J JACKSON]

Re: Merc 470 convert to open system ? Why Not

jason from the looks of that rod that's a ventilated open deck design

 

[chiefalen]

Re: Merc 470 convert to open system ? Why Not

Ok one last one from me on this thread. It was actually only 3 years they put out that motor. And pity the poor souls who purchased a boat with it in in.

Weight vs hp on paper made it a outstanding choice, but it's only on paper.

There was no real alternator on the motor, it's a outboard, small engine type stator design. They came out with a kit to convert it to a conventional alternator, price 400-600.

What a interface, jap, overhead cam, car motor comparison is doing on this thread, went over my head.

You cant run saltwater straight thru the head after a week it will be frozen.

Now to running at 190 degree 4.3 motor all the time when it's supposed to run at 160 is just asking for trouble.

But i guess you may get away with it but wouldn't it shorten the life span of the motor?

Finally heres a link you decide if your going to keep it.

http://forums.iboats.com/showthread.php?p=1909331&posted=1#post1909331

 

[abj87]

Re: Merc 470 convert to open system ? Why Not

Now to running at 190 degree 4.3 motor all the time when it's supposed to run at 160 is just asking for trouble.

But i guess you may get away with it but wouldn't it shorten the life span of the motor?

In the automotive application they run even hotter than that. The hotter the engine runs the more efficient it is, thermo 101 here. The reason it runs at 160 is because any hotter than that the salt will precipitate out of the water and build up the cooling passages.

 

[chiefalen]

Re: Merc 470 convert to open system ? Why Not

Oh you mean someone might want heat in the car.

Again why the car comparison. and by the way we want the motor running around 140-160.

No heater core to draw the heat out for a heater.

 

[abj87]

Re: Merc 470 convert to open system ? Why Not

Oh you mean someone might want heat in the car.

Again why the car comparison. and by the way we want the motor running around 140-160.

No heater core to draw the heat out for a heater.

Did you miss the part about efficiency???

 

[slasmith1]

Re: Merc 470 convert to open system ? Why Not

Oh you mean someone might want heat in the car.

Again why the car comparison. and by the way we want the motor running around 140-160.

No heater core to draw the heat out for a heater.

Try reading this thread about temp and effiency in a marine application chief.
http://forums.iboats.com/showthread.php?t=288859

 

[chiefalen]

Re: Merc 470 convert to open system ? Why Not

I posted to that thread remember it well.

How hot you want it to run, Merc has 140 t-stat, omc 160, 180 is kewl to run at anyone want to tell me 190 is good, 200, is good how about over 212 where water boils?

What is the best temp to run at??

 

[rodbolt]

Re: Merc 470 convert to open system ? Why Not

out of memory the operating range from merc on the 3.7 was something like 165 to 205*F.
that was acceptable.
as its freshwater closed cooling scaling of minerals wasnt an issue.
the hotter you can run a 4 stroke the better its fuel efficiency, however as the heat increases so does the danger of mechanical failure.
its also why most all sterndrive Tstats are now at least 160 and automotive is between 195 and 210
yes water boils at 212 at sealevel.
50/50 AF mix does not.
as we raise the pressure inside the cooling system even pure water boils at a much higher temp.

but to go back to the question. dont do it cause it wont work, trust me.

some 3.7L motors are actually still running today despite being out of production almost 20 years.
however yesterday I saw an Edsall cruising down HWY 343.
doesnt mean it was a fine ride just means one survived.

 

[Don S]

Re: Merc 470 convert to open system ? Why Not

however yesterday I saw an Edsall cruising down HWY 343.

Spelled Edsel by many

Followed closely by a DeSoto pulling a boat with a 470 in it.

There is an exception to every rule. Especially those rules of thumb.

 

[rodbolt]

Re: Merc 470 convert to open system ? Why Not

chops busted
I accept it.
but I still drove a 61 studebaker lark most my high school years

one day I am gonna show up at your shop and either give you a red dot or a bottle of crown royal.
day may be comeing soon

 

[Don S]

Re: Merc 470 convert to open system ? Why Not

That wasn't chop bustin' that was jus plain ole "Givin' ya sh**"

 

[slasmith1]

Re: Merc 470 convert to open system ? Why Not

Don does all this mean that the 470 is the force of the I/O world?

 

[rodbolt]

Re: Merc 470 convert to open system ? Why Not

yep its all about the force.
still dunno when I meet DonS, do I give him another red dot or a bottle. ??????

 

[Don S]

Re: Merc 470 convert to open system ? Why Not

still dunno when I meet DonS, do I give him another red dot or a bottle. ??????

Bring the bottle, I'll furnish the 470 and a stirnger drive, and a wierd boat with 57 Caddy fins. We will put together a boat that is the worst of the worst. Then, we'll send it back with you so you can do some serious salt water testing. But keep one thing in mind. NO MAINTENANCE allowed. Run er till she pukes. Then we will post on iboats for help and never tell anyone what we did

 

[rodbolt]

Re: Merc 470 convert to open system ? Why Not

heck with them thare loose specs we can get to the gulf stream and maybe back.

 

[Bondo]

Re: Merc 470 convert to open system ? Why Not

Bring the bottle, I'll furnish the 470 and a stirnger drive, and a wierd boat with 57 Caddy fins.

Ayuh,.... That's Weird,....

 

[rodbolt]

Re: Merc 470 convert to open system ? Why Not

best I just bring the bottle asnd invite DonS and a friend out to dinner.

 

[slasmith1]

Re: Merc 470 convert to open system ? Why Not

Bring the bottle, I'll furnish the 470 and a stirnger drive, and a wierd boat with 57 Caddy fins. We will put together a boat that is the worst of the worst. Then, we'll send it back with you so you can do some serious salt water testing. But keep one thing in mind. NO MAINTENANCE allowed. Run er till she pukes. Then we will post on iboats for help and never tell anyone what we did

I'll write the craigs list ad for it after you break it.