mercruiser 470 winterizing?

[ll05]

Hello,

I have a 1984 18ft Chaparral with the 470 in it. I am in Oklahoma, and it gets below freezing here. I know I need to winterize, but I am confused on what needs to be done to this particular engine, because of its cooling system.

I have read the sticky on winterizing and I am confused.

Can anyone shed some light on the correct procedure for this engine? I am unsure of where the drain plugs are as well.

I appreciate any and all help!!!

Thanks,

Lee

 

[HT32BSX115]

Re: mercruiser 470 winterizing?

Well you could do it the way I winterized my closed-cooled 454.

Just draw some 50/50 AF up into the raw-side of the cooling system using a set of muffs and a short piece of hose and a tub-like container of anti-freeze. Position the container of AF so that the discharge runs back into it while the hose

Let it run long enough to circulate the AF thru the system until it starts to get fairly warm. Fog the engine before shut down.

(you might also consider changing the oil and drive oil too.......and if you haven't ever removed the drive, now is a good time to do it)

Your other choice is to drain the heat exchanger, PS/oil coolers, and exhaust elbows.

Either way works. I like my way since any pooled water is antifreeze. (and it's a royal pain to drain my PS and oil coolers)


Regards,


Rick

 

[sea wolf]

Re: mercruiser 470 winterizing?

Hello,

I have a 1984 18ft Chaparral with the 470 in it. I am in Oklahoma, and it gets below freezing here. I know I need to winterize, but I am confused on what needs to be done to this particular engine, because of its cooling system.

I have read the sticky on winterizing and I am confused.

Can anyone shed some light on the correct procedure for this engine? I am unsure of where the drain plugs are as well.

I appreciate any and all help!!!

Thanks,

Lee

Read Don's sticky & follow THAT procedure. It's the only way to ensure that you're not back here come spring looking to repair or replace your cracked block & or manifolds.

 

[ll05]

Re: mercruiser 470 winterizing?

I have read the winterizing post. I am interested in the winterizing specifics for this particular engine. I know it is a closed cooling system, so I want to know what the winterizing differences are.

I appreciate your post.

Thanks,

Lee

 

[HT32BSX115]

Re: mercruiser 470 winterizing?

The main differences are what you're protecting from freeze damage.

With closed cooling you have to only worry about the parts that might contain raw water. The block, head, and exhaust manifold circulating pump, thermostat housing etc...contain anti-freeze coolant.

The "raw side" of the heat exchanger, power steering & oil coolers (if equipped), raw water pump, exhaust elbow, other raw water hoses and possibly the lower unit might contain pooled freeze-able water. You must either drain those components or put AF in there.

If you're absolutely sure you have drained all the water, that's the best way. "Air don't freeze" (at least on this planet) You can also flush the raw side with an AF mix.

Your choice.


Cheers,

Rick


Oh, and by the way, since it appears that you might want to do this or other maintenance, now would be a good time to get a Mercruiser service manual unique to your engine/drive if you don't already have one.

 

[fireman02169]

Re: mercruiser 470 winterizing?

Hey, same issues here. I have an '87 Regal with the 165 hp Merc 470.
Seems to me like you can drain the antifreeze side at the bottom rear of the heat exchanger (The tube shaped thingy on the left side of the motor) It is the forward most plug. flush the antifreeze side with cleat water by running it through your antifreeze reservoir and then refill it with new glycol-based antifreeze.
The plug just aft of it I believe is the raw-water (seawater/freshwater) drain. Im pretty sure if you take the small hose off of the water cooled voltage regulator (square thing above the heat exchanger attached to the motor) and pour -60 antifreeze into it until it comes out of your stern-drive, it should sufficiently flush/dilute the raw water in there. The hose im talking about connects to the front top of the heat exchanger. leave that end on, take the end off of the voltage regulator and pour -60 antifreeze into it.
Can anyone confirm this?

 

[stonyloam]

Re: mercruiser 470 winterizing?

NO NO NO!!!!! Ignore all above this post!!!! To winterize a 470 you: CHECK the antifreeze, it should be about 50% (-34 F). DRAIN the seawater side of the heat exchanger, the aft plug. Make sure the power steering cooler drains, remove the hose if necessary. Once drained put the hose back on and the plug back in with a little NAPA aviation sealant. That's it DONE!! I pull the boat plug and drain the exchanger (it is clean water) right on the ramp when I pull the boat for winter.

 

[stonyloam]

Re: mercruiser 470 winterizing?

Hey, same issues here. I have an '87 Regal with the 165 hp Merc 470.
Seems to me like you can drain the antifreeze side ........
The plug just aft of it I believe is the raw-water (seawater/freshwater) drain. Im pretty sure if you take the small hose off of the water cooled voltage regulator (square thing above the heat exchanger attached to the motor) and pour -60 antifreeze into it until it comes out of your stern-drive, it should

You don't need to drain the antifreeze side, because it is well .... filled with antifreeze. Just make sure it is up to spec about 50% (-34 F)

The voltage regulator should drain out through the outdrive, however if you are worried about it, just pull the hoses and let it drain, no need to fill with af. Only thing to worry about is the PS cooler (if you have one), make sure it drains.

 

[Eric 3.7LX Alpha 1]

Re: mercruiser 470 winterizing?

There are 2 drain plugs on the bottom of the exchanger, the aft plug is seawater side drain. I actually have a 1/4" zinc as part of that plug which I replace yearly. Not sure if it was original but I have been using one since I had the boat, and it does get worn down.

Or you could remove the end cap and drain that way.

From manual #8:

 

[stonyloam]

Re: mercruiser 470 winterizing?

Very nice Eric Could you do the same with Pages 6A 11 and 12 (manual #8 cooling system) they specifically talk about draining the seawater? Thanks.

 

[Eric 3.7LX Alpha 1]

Re: mercruiser 470 winterizing?

Done:

 

[rodbolt]

Re: mercruiser 470 winterizing?

its just to simple to mix 1 gallon concentrated non toxic A/F with 4 gallons of water,place the 5 gallons of mix higher than the seawater pump, use a hose and a flush muff.
run the 5 gallons through and presto ALL seawater cooled parts ARE protected and you didnt get a chance to skin a knucle or braek a fastener.
this only works for CLOSED cooling.
raw water cooled engines require the block to be drained PRIOR to running the A/F mix through it.
and cast iron is porous, air dry it and watch the water bleed for weeks and the rusticles form.
use the non toxic poly A/F so it doesnt kill things and is legal to discharge.

 

[stonyloam]

Re: mercruiser 470 winterizing?

its just to simple to mix 1 gallon concentrated non toxic A/F with 4 gallons of water,place the 5 gallons of mix higher than the seawater pump, use a hose and a flush muff.
run the 5 gallons through and presto ALL seawater cooled parts ARE protected and you didnt get a chance to skin a knucle or braek a fastener.
this only works for CLOSED cooling.
raw water cooled engines require the block to be drained PRIOR to running the A/F mix through it.
and cast iron is porous, air dry it and watch the water bleed for weeks and the rusticles form.
use the non toxic poly A/F so it doesnt kill things and is legal to discharge.

Can you do that in under 2 minutes........ for free? That is how long it takes me....... if I am slow. My ps cooler is above the exchanger and drains into it. The "book" says drain. 1/4 inch drive ratchet on one plug DONE!

 

[nola mike]

Re: mercruiser 470 winterizing?

its just to simple to mix 1 gallon concentrated non toxic A/F with 4 gallons of water,place the 5 gallons of mix higher than the seawater pump, use a hose and a flush muff.
run the 5 gallons through and presto ALL seawater cooled parts ARE protected and you didnt get a chance to skin a knucle or braek a fastener.
this only works for CLOSED cooling.
raw water cooled engines require the block to be drained PRIOR to running the A/F mix through it.
and cast iron is porous, air dry it and watch the water bleed for weeks and the rusticles form.
use the non toxic poly A/F so it doesnt kill things and is legal to discharge.

why would you drain a FWC block before adding a/f, but NOT drain the FWC parts on a closed system? as long as you're filled with a/f, there is NO chance of the block freezing on a 470. worst case, even if you don't drain, is a busted heat exchanger/riser. but i'm with terry on this one...pull aft plug, poof, winterized 2 minutes later.

 

[HOLYSMOKES]

Re: mercruiser 470 winterizing?

GREAT THREAD guys! Again, thx for all of the information. There are some of us that are still learning the ropes and are making an effort in doing things correctly. After all, its why we are here!

 

[rodbolt]

Re: mercruiser 470 winterizing?

biggest difference?
if you miss a drain and something busts or the riser doesnt drain and cracks you get to post about it come spring.
if I winterize an engine and miss an engine oil cooler,power steering oil cooler heat exchanger or riser I get to repair the damage on my nickle next spring.
I only winterize a couple hundred engines a year, and have for about 15 years.
havent lost anything yet.
some 3.7L motors had engine oil and powersteering oil coolers that the drain plugs liked to strip or break off,the A/F method means I dont have to mess with drains.