Volvo Penta 570 Freshwater Cooling Retro

[Hook'd]

I have a recently acquired 570 with a few hundred hours used solely in saltwater. The owner took great care. I will use exclusively in salt.

I want to add a freshwater system for obvious reasons.

It has power steering, which limits the specific system, but I am considering eliminating the PS as I go to a hydraulic setup for auto pilot.

1. What are the pros and cons of a freshwater system...seems like a no-brainer, but would appreciate feedback?
2. I believe this engine is limited to a half system with the older style manifolds. Is this true?
3. Is the half system a typical retro installation?
4. Is there any reason to consider new manifolds (if needed)/ a full system?
5. Who do you like for the retro kit?
6. Words of wisdom?

Thanks for the feedback!

 

[Maclin]

Going to Freshwater cooling after an engine has been run for a few years, especially in salt, can cause flakes of corrosion to get circulated around and clog things up in short order. I believe it is not recommended.

 

[alldodge]

I have a recently acquired 570 with a few hundred hours used solely in saltwater. The owner took great care. I will use exclusively in salt.

I want to add a freshwater system for obvious reasons.

It has power steering, which limits the specific system, but I am considering eliminating the PS as I go to a hydraulic setup for auto pilot.

1. What are the pros and cons of a freshwater system...seems like a no-brainer, but would appreciate feedback?
2. I believe this engine is limited to a half system with the older style manifolds. Is this true?
3. Is the half system a typical retro installation?
4. Is there any reason to consider new manifolds (if needed)/ a full system?
5. Who do you like for the retro kit?
6. Words of wisdom?

Thanks for the feedback!

Howdy

Agree with Maclin, don't do it. It is not recommend to do a change over a open fresh water cooled motor after 100 hours, salt is even less. While you can do it, and if you proceed, I would recommend changing out the antifreeze for the next couple seasons, include cleaning exchanger and clean/replace thermostat and keep close eye on the tem gauge.

Change manifolds if after inspect it would be advisable

Use half system if you do not change exhaust, go full if you replace exhaust

To further answer your questions you need to tell us what engines you have and year
Edit: never mind appears you have a 5.7L

 

[Hook'd]

Maclin and AllDodge, Thanks for the feedback....I hadn't thought of that. So how much do these kits actually improve longevity versus properly flushing after each time on the water?

 

[alldodge]

Maclin and AllDodge, Thanks for the feedback....I hadn't thought of that. So how much do these kits actually improve longevity versus properly flushing after each time on the water?

The kits can extend the engine longevity by a significant amount when used in salt water. Your motor should have it, the issue is it's a bit late to install. This isn't to say you cannot make it happen, just will take more maintenance until the scaling breaks loose and is cleaned out.

You cannot flush an engine enough normally, the thermostat opens and closes and therefore salt is left in the motor. It takes more then 20 minutes to flush it

 

[Hook'd]

Ok, if I were to do it, who would you recommend to purchase the kit from. Maybe a manufacturer would have advice.

 

[Lou C]

I would not do it as noted above. I have a raw water cooled engine used in salt for years. What I do when winterizing is this: flush the engine thoroughly, then manually drain engine and manifolds. Next back fill the engine and manifolds with the best -100 marine antifreeze. This does work to prolong engine and manifold life and I do not see rusty water come out when I start it for the first time in the spring. Volvo sells their Neutra Salt system which kind of does the same thing. I think if you try to add closed cooling after salt use you may regret it due to chronic clogging and overheating. The time to do it is when you re power with a new engine.

 

[jerryjerry05]

The original manifolds can't be hooked up on FWC. You can change to another brand.
The shale/crud can't be removed unless you dismantle and acid dip the block(get a new block)
Salt corrosion once started won't stop. Air accelerates the corrosion. Never drain and leave empty, use a good marine anti-freeze(lou)
If it's original? 1989-93 Time for manifolds anyway??
Or just run the heck out of it!!

The engine should last longer if a FWC system is used from the start.
I see no real benefit from changing now.
Get a new block and Mercriser manifolds.
Don't buy a used FWC system.
They're like a radiator they can clog after time.

 

[Lou C]

Just to re-cap, having done it myself, besides doing the drain and fill with the best AF winterization thing, the other very very important thing is to maintain that exhaust system very strictly. That means, you don't go more than 5-7 years on the same manifolds and risers. And, if you see any leaking on the outside of the riser/manifold joint, you drain the manifolds and inspect that sealing surface area and the water passages right away. Because, if its leaking outside, it could be leaking inside. Bad/leaky/internally corroded exhaust is what does in most salt water inboards. The engine block and heads won't rust out for a long time because they are not exposed to hot exhaust gases.

 

[Ned L]

Hmm,.. This is the first time I have ever heard 'don't do it' for other than cost reasons. I'm changing my engines to FWC before the boat hits the water this year. ... The age of the engines? 1957. (At least one anyway, I think the other had a new long block in 1979.)

Maybe the cast iron used today is crappy??

Sen-Dure is one of the top names in FWC kits.

 

[alldodge]

Hmm,.. This is the first time I have ever heard 'don't do it' for other than cost reasons. I'm changing my engines to FWC before the boat hits the water this year. ... The age of the engines? 1957. (At least one anyway, I think the other had a new long block in 1979.)

Maybe the cast iron used today is crappy??

Sen-Dure is one of the top names in FWC kits.

The quality of the cast iron is not the issue, it's all the build up that has collected over time. A raw cooled engine will just spit the stuff out as it breaks loose. Antifreeze will break the stuff loose more often and it will continue to circulate and clog things up.

 

[Ned L]

Hmmmm, ...... ok. (Still going forward on my Chrysler Crowns though.)

 

[bruceb58]

I called up San Juan regarding an engine that only had 70 hours on it and they said not to do it.