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Retro fitting Closed Loop cooling to 5.0 GXi-F V8

After reading thru this thread, all I can do is ask why not just put the boat on a trailer and forget all this nonsense? Does it have to sit at a pier all the time? The advantages of having the boat on a trailer v sitting in the water are just so compelling. Is it cz Daughter doesn't have the means to get the boat to a ramp or it's too far away? How about a lift? A lift would add value to the property that you will recoup eventually thru either equity or selling. They aren't all that expensive. That gets the boat out of the water, and you just flush it out with sweet water after a run in the briny. You're gonna hose it down anyway right?
 
Further Hijack!!!

Rick,

re: hearing... It was a tight fit I used a pair of Centek Vernatone(tm) MiniMax @ 3" port size. Even at that, I had to cut about 1/2" off of the pipe flanges on each end to get them to fit! Insofar as my hearing... At idle it is louder but it has a nice mellow tone. At cruise, its actually quieter! Sound thru the mufflers is quieter than the sound thru the 280's exhaust port which as you very well know (benefit of non 280 owners) is above water at cruise and essentially has no sound reduction at all. My wife and I can actually now carry on a conversation at the helm on my wide open boat! Admittedly not at normal conversational levels, but not at a full shout as before.

I wanted to use Salisbury's this time again as I was very pleased with them on my first project, however, they are no longer made! From time to time they show up used.

When I tried to edit my webpage, I found out that Comcast without telling me had discontinued offering their free customer webpage feature and sometime after april of this year, stopped existing webpages from being edited. My wife has convinced me to convert the content to a Facebook page. Note: Keep a eye on the horizon for a 4 big ugly guys on horses :)
 
o2batsea said:
After reading thru this thread, all I can do is ask why not just put the boat on a trailer and forget all this nonsense? Does it have to sit at a pier all the time? The advantages of having the boat on a trailer v sitting in the water are just so compelling. Is it cz Daughter doesn't have the means to get the boat to a ramp or it's too far away? How about a lift? A lift would add value to the property that you will recoup eventually thru either equity or selling. They aren't all that expensive. That gets the boat out of the water, and you just flush it out with sweet water after a run in the briny. You're gonna hose it down anyway right?
Click to expand...

Hi batsea
You see the situation is that we do not have any room for a trailer, the house extends across the whole width of the property!!
But more importantly as I see it, is the fact than we can just walk to bottom of the garden get in the boat and sail away,
The guy who I bought the boat from spent over $2,500 (I have the invoices) on service to the trailer!!! And there is the cost of petrol for a large 4WD to pull the thing, trailer and boat weigh 3 tonne. In OZ the dept of main roads are beurocratic and dictatorial concerinign trailers that pull anything more than 1 tonne. Would you believe that the trailers you use in the US are not road legal here!!!!
To add to our frustration in the land of the "free" the maritime beurocrats do not permit the use of floating boat lifts in the state of N S W. they consider them to be unsitely and to collect growth. Although one person has sugested that this could be challenged in court.

In any case the fact that the boat originally lived on a trailer really is of no consequense, there are millions of smaller boats that spend their time in the water (fresh or salt) It just happens that this particular machine had been fitted with a brand new leg was selling at a very reasonable price and was of a sensible size for a first boat.
I must say that had I been a member of this very helpful forum 6 months ago, my decision might have been different. I would have looked for a boat with full/half cooling, and spent more cash up front. At least I opted for a Volvo Penta which makes the problem of changing the impeller/pump go away as it can so easily be done in the water at little cost, or even a larger one fitted.

The fact that it has only been used in fresh water was an additional attraction, and is why I am trying to conserve it's almost new condition by fittting a closed circuit cooling system.
 
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Hi Rick,
( I am not an expert in this area.... but I'd take a stab here by suggesting that the flushing chemical may help prevent future salt crystallization from forming... but I have my doubts that the chemical would remove existing crystallization scale.)

The boat has only been used in fresh water that's why I thought that using this stuff might at least ward off any onset of corrosion or salt accumulation until I get the cooling system sorted.
When the engine was running on the trailer the water was coming out very clear, although I did not think to collect some in a bucket as you sugest.
This is why I am concerned about whether only the water/chemical mix circulates through the engine when I connect up the flushing hose to the
engine flush connection. As far as I can see there is a "Y" connection to the raw water hose feeding into the impeller pump which could produce a form of venturie action sucking in sea water.
 
Hi back.......

nimbus said:
Hi Rick,
Rick said:
I am not an expert in this area.... but I'd take a stab here by suggesting that the flushing chemical may help prevent future salt crystallization from forming... but I have my doubts that the chemical would remove existing crystallization scale.
Click to expand...
The boat has only been used in fresh water that's why I thought that using this stuff might at least ward off any onset of corrosion or salt accumulation until I get the cooling system sorted.
It may, but again, I've seen no data..... only claims.

When the engine was running on the trailer the water was coming out very clear,
After initial start-up, it will always appear to be clean.

although I did not think to collect some in a bucket as you sugest.
My suggestion was for after the "closed cooling system" installation, and after XX hours of run time, to drain the E/G from H/E, then remove it, then add hot soapy flushing water, shake it up..... and then drain contents into clean white bucket as to see how much rust scale has been dislodging from the internals of the cylinder block/heads.

I would suggest this to anyone who is installing a closed cooling system on any previously raw water cooled engine..... either fresh water or ocean water!

This is why I am concerned about whether only the water/chemical mix circulates through the engine when I connect up the flushing hose to the engine flush connection.
Perhaps read this write-up I did in October 2012. It will relate to your question.

As far as I can see there is a "Y" connection to the raw water hose feeding into the impeller pump which could produce a form of venturie action sucking in sea water.
I'm not following you on this one.
Are you refering to a flushing kit?
Click to expand...

Just an FYI:
While I prefer closed cooling systems, hundreds of thousands of boats have been successfully using "open" systems in salt water and for years.



.
 
Re: "but I'd take a stab here by suggesting that the flushing chemical may help prevent future salt crystallization from forming... but I have my doubts that the chemical would remove existing crystallization scale."

I've got some limited hands on experience with this with my HONDA 7.5 HP 4cycle... Several years ago the bypass indicator flow slowed to a dribble. I pulled the engine and put it in a large bucket filled with a salt-away solution (diluted with the inline mixer) a similar product to the one mentioned. After running for about 2 to 3 mins, the flow increased, by 5 min, it was full flow. The next spring, I pulled the intake manifold ( on that Honda, this includes the t'stat housing and the bypass, etc.). While the bypass was still clear (due to high flow rate I assume), the T'stat itself was pretty gunked up. Rather than buy a new t'stat ( every "cost effective" am I !) I soaked the T'stat in a cup of vinegar overnight and the next morning it was like new. I tested it and it was OK.... so back in the engine. Removed salt deposits from the rest of the intake's water passages with vinegar soak and scraping. Back together... all ok for a few seasons. Subsequently found out that the accumulation of deposits in the cooling passages was due to a manufacturing defect in which the bypass nipple fitting had an obstructed flow, and the cooling passages did not drain completely when the engine was tipped up.

The previous owner of my 1969 Lancer had religiously flushed the cooling system with just plain fresh water (boat spent its whole life in salt water) every time he used it ( he had installed a valved "T" just in front of the raw water pump) and when I bought it 9 years ago, the original engine (but not elbows or manifolds) was still OK. That's 36 years running in sea water! I ran it one season (no problems!) and then re-engined it.
 
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Hi Rick,
(As far as I can see there is a "Y" connection to the raw water hose feeding into the impeller pump which could produce a form of venturie action sucking in sea water.
I'm not following you on this one.
Are you refering to a flushing kit? )

No, what I was refering to was the effect that a fast higher pressure flow of water would tend to suck in water from a another connected pipe in the system.
In fact I had a very helpful discussion with the tech rep. for Volvo here in Sydney.
He explained that the incoming water from the garden hose would in fact split two ways with some of it going out of the leg and the larger part going into the engine when running. From what I could understand Volvo did fit some sort of ball valve on the incoming water from the leg in earlier models. But I guess this could be a problem if people forgot to turn it on again when starting the engine!! also the fresh water does also help to keep the leg clean.
For those with Volvo engines there is a warning in the operators manual that states that only those engines fitted with the BLUE flush connection should be run when flushing.
 
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nimbus said:
No, what I was refering to was the effect that a fast higher pressure flow of water would tend to suck in water from a another connected pipe in the system.
In fact I had a very helpful discussion with the tech rep. for Volvo here in Sydney.
He explained that the incoming water from the garden hose would in fact split two ways with some of it going out of the leg and the larger part going into the engine when running.
If you use one of the Perko flushing kits, there is a check valve that would prevent potable water from going towards the drive.

From what I could understand Volvo did fit some sort of ball valve on the incoming water from the leg in earlier models.
Not to my knowledge. I've worked on most all of them from the early 1970's 250s and on.

But I guess this could be a problem if people forgot to turn it on again when starting the engine!!
This is part of why you do not want a system that requires this.
KIS... keep it simple.

also the fresh water does also help to keep the leg clean.
If moored in the water.... I doubt it.

For those with Volvo engines there is a warning in the operators manual that states that only those engines fitted with the BLUE flush connection should be run when flushing.
You may be reading info for engines/drives after the AQ series, or you're reading Mercruiser info.
Stick with the AQ series info.
Click to expand...
 
(For those with Volvo engines there is a warning in the operators manual that states that only those engines fitted with the BLUE flush connection should be run when flushing.
You may be reading info for engines/drives after the AQ series, or you're reading Mercruiser info.
Stick with the AQ series)
Can you define what the AQ series is? mine is mid/late 2006 engine and the SELOC Volvo manual is for 2003-2012 models in which it warns about flushing.
It does not worry me cos I have the Blue coloured flush connection.
 
My apologies. I was mistaken, and was confusing your thread with another thread!
You do have one of the later drives… Not an AQ series.

The AQ series drives use main suspension fork and pivot tube geometry.
Your stern drive uses gimbal system suspension geometry.




.
 
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Well today I went out and bought myself a length of 41/4" plastic drain pipe which I cut into a length of 26" as a template for the HE
This is where I got my first surprise the front removable bulkhead of the engine bay is far too close to fit a HE tube af any dia.
but in a Monterey there is acres of room either side of the engine. Most of it wasted space I reckon. A 6" X 30" HE would easily fit lengthways to the engine so this is where I will place it. It will mean that some of the connecting hoses will be longer than normal but I don't think this will be a problem.
 
nimbus said:
Well today I went out and bought myself a length of 41/4" plastic drain pipe which I cut into a length of 26" as a template for the HE
This is where I got my first surprise the front removable bulkhead of the engine bay is far too close to fit a HE tube af any dia.
but in a Monterey there is acres of room either side of the engine. Most of it wasted space I reckon. A 6" X 30" HE would easily fit lengthways to the engine so this is where I will place it. It will mean that some of the connecting hoses will be longer than normal but I don't think this will be a problem.
Click to expand...
We will occasionally see a remotely mounted (off-engine) H/E. However, if you were to do this, I would give this some careful thought before purchasing the H/E .... in terms of the port configuration.

It can be done!


.
 
yes I had thought of the porting locations, there will be more than enough room under the HE so I was intending to double clamp all those hoses that come out from under the HE and then cut them to length when it is in position./
This may seem to be a silly question but given that we discharge all the sea water into the top of the elbows presumedly to cool the exhaust and reduce noise. Why do the exhaust manifolds need to be cooled?? is it a safety thing or a reason that I have not understood. I have never come across cooled manifolds in auto engines that I can recall. In high powered engines running flat out I have seem the exhaust pipes glowing red hot, would this happen in a marine engine?
 
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nimbus,check out HI-TEC marine in brisbane,they make one piece stainless manifolds,suitable for half systems,no more corosion,run cooler,and look good,also make through hull muffler systems,am using on a raw water system conversion on a merc 5ltr,the original cast ones rotted through and caused a major rebuild to the engine.
 
nimbus said:
This may seem to be a silly question but given that we discharge all the sea water into the top of the elbows presumedly to cool the exhaust and reduce noise. Why do the exhaust manifolds need to be cooled??
is it a safety thing or a reason that I have not understood. I have never come across cooled manifolds in auto engines that I can recall. In high powered engines running flat out I have seem the exhaust pipes glowing red hot, would this happen in a marine engine?
Click to expand...

If you have ever seen HP Auto Engine exhaust manifolds or tube headers at night (just after a hard run), you've seen that they will glow red hot!

Marine engine loads are heavy, and the load duration is greater. Any item within the enclosed engine bay cannot be allowed to produce a fuel vapor ignition source. By water or E/G cooling these, the ignition source is eliminated.

On boats whereby the engine is NOT enclosed, the exhaust is still wet. It may perhaps be wet near the outlets only ... but nonetheless, still wet.


.
 
Hi Kunbarrie,
Many thanks for the tip on Hi-Tech.
In fact they are "Hi-TEK" in Brisbane. 'Hi-Tech' are based in WA and manufacture Merc manifolds and risers using the new lost foam casting technology which is supposed to be far superior in maintaining wall thickness. They supply the 'dry joint' type system and for FWC applications.

It's amazing they are both in OZ and I did'nt know about them!!
I will call Hi-TEK on Monday and find out how many gold bars I require to pay for a set. They have a great pic of a set fitted to a GXi engine.

But in the long run I recon that the Merc 'dry joint' type of manifold is far superior to the Volvo (or old Merc types) in that water cannot leak into the engine as the water connection between the two joints is outside the exhaust passage way.
This is the system I would prefer based on all the excellent and informed advice I have received here. But I cannot establish that a Merc set of Manifolds elbows definitely fit the Volvo 5Lt engine.
Capt Bob seems to be sure that the Merc mainfolds will fit the Volvo. I guess they should as the blocks are the same. Connecting up the 'Y' pipe seems to be the biggest problem fo me as there is no 'open sky' access to the rear of the engine.
If I go along this route will I need a new Thermostat housing for FWC and will it fit the Volvo??
I have decide that the HE will have to go at the LHS of the engine where there is plenty of space, connected with generic lengths of flexible hose to the water connections. So the type of HE I use is not too important so long as the filler cap is close to the front of the engine bay.
I am trying to obtain a set of old manifolds for both engines so I can compare the dimentions
 
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nimbus said:
In fact they are "Hi-TEK" in Brisbane. 'Hi-Tech' are based in WA and manufacture Merc manifolds and risers using the new lost foam casting technology which is supposed to be far superior in maintaining wall thickness. They supply the 'dry joint' type system and for FWC applications.
Just a thought:
If in a Half Closed Cooling system scenario, the dry joint is of value.
However, since the Full Closed Cooling system separates the manifold from the elbow, the dry joint concept is of no real value.



But in the long run I recon that the Merc 'dry joint' type of manifold is far superior to the Volvo (or old Merc types) in that water cannot leak into the engine as the water connection between the two joints is outside the exhaust passage way.
As you know, the exhaust gas passage and the seawater transfer ports are separated greater with the dry-joint system.... in other words, there is more material between the two areas.
(See image below)

This is the system I would prefer based on all the excellent and informed advice I have received here. But I cannot establish that a Merc set of Manifolds elbows definitely fit the Volvo 5Lt engine. Capt Bob seems to be sure that the Merc mainfolds will fit the Volvo. I guess they should as the blocks are the same. Connecting up the 'Y' pipe seems to be the biggest problem fo me as there is no 'open sky' access to the rear of the engine.
Minus any mounting bosses for electronics.... they will fit the SBC engine!
The issue will be the elbow down angle, and whether or not the elbow alignment to the Y-pipe can be accomplished easily.


If I go along this route will I need a new Thermostat housing for FWC and will it fit the Volvo??
You will need to change this housing whether you go with a Half or Full system.
Click to expand...
 

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Thanks Rick for advice, I must admit that going along with the fitting of Merc exhaust/elbows apeals to me if it were not for the unknown concerning the elbows and 'Y' joint fitting.
Concerning the SS kits available from Hi-TEK they cost $2,500 for a complete set and Allen tells me that they are fitted internally with an exhaust extraction system which gives an additional 35HP !!! they are also half the weight. They are made from a special SS. My guess is that this would be some type of alloy used in the oil/nuclear industry.
He says that FWC is totally unneccesary with these units and that a half system is all that is required to protect the block.
 
nimbus said:
going along with the fitting of Merc exhaust/elbows apeals to me if it were not for the unknown concerning the elbows and 'Y' joint fitting.
Concerning the SS kits available from Hi-TEK they cost $2,500 for a complete set and Allen tells me that they are fitted internally with an exhaust extraction system which gives an additional 35HP !!! QUOTE]

When I re-engined my boat, the original engine was a Chris Craft 283 marine conversion.
The mechanic that did the conversion, cut the "Y" pipe off about 4 to 6 inches from the bottom and was able to route from there to the MERC elbows via standard marine plumbing, i.e., a 72 degree elbow, a 4 inch to 3 inch reducer and marine exhaust hose and clamps.
Click to expand...
 
Have spent a bit more time looking at the SS systems.
They seem to be the best thing since sliced bread, they only weigh 17Kg and are a one-piece construction, no joints between the manifolds and elbows.
 
Hi Bob,
interesting paper on elbows. It would seem that the greater the angle the better within reason.
I have no idea what the inside of the SS unit looks like and I doubt if hi-TEK will give me the details.
 
nimbus said:
Hi Bob,
interesting paper on elbows. It would seem that the greater the angle the better within reason.
I have no idea what the inside of the SS unit looks like and I doubt if hi-TEK will give me the details.
Click to expand...

You might consider forwarding them the link to the paper and asking for their comments...
 
Hi folks,
Well; after all the above help and advice and re-reading all of it I have decide to go for an 'engine only' closed cooling system and fit the integral SS manifold/riser (elbow) units. To me this seems to be the better option. After trips I have done a few flushings using the onboard flushing attachment and salt neutraliser, and it all seems to be a real pain in the butt!!! I guess not having to do all of this makes boating that much more relaxing, especially for my daughter and husband who are not mechanically minded.
All I need to do now is select the apropiate cooling system for the engine.
I must admit if I had known now what I have learned here I would have chosen a boat fitted with cooling. Hindsite is such a wonderful thing!!!
 
Well at last the heat exchanger unit has been ordered together with an oil cooler which did not cost that much more as it was all included in the one shipment cost to Australia. Hope to get in the next 14 days. I intend to mount it along the side of the engine on the starboard side.
Now I have one problem that maybe some of you have already encountered when converting to closed cooling.
On my Volvo V8 there is the normal thermostat housing with two outlets at the back which currently go to the two exhaust manifold connections.
and of course there is the inlet from the raw water pump. This will now connect to the HE.

I had intended buying the two part replacement thermostat housing for Block cooling from the Volvo suppliers here, as it seemed to be the more ellegant solution, but the cost is A$800.00!!!! nearly US$1,000 at the current exchange rate!!!

So now I intend to connect the two existing outlets (to the exhaust manifolds) together with a "T" connector pipe and connect this back to the HE.
Is this the correct thing to do???
I have not been able to locate any specific installation instructions for the conversion process concerning Volvo Penta V8 engines.
 
Volvo V8 with SS Exhausts.jpg
The image is a picture of a Volvo 5Lt V8 fitted with SS integrated exhaust/risers.
The two blue pipes in the image are the pipes that I am talking about. in this image they go to the two inlets to the SS manifolds.
On my current engine they go to the CI exhaust manifolds.
When I fit the HE I intend to connect these pipes together via a "T" pipe and feed the water back to the HE.
In the Volvo closed cooling system these outlet pipes from the thermostat housing do not exist.
I saw an image of the "T" pipe somewhere in an arctical on cooling , I believe it related to a Mercruiser but the water ciruit must surely be much the same for both makes.
 
................................

nimbus said:
View attachment 10295


The image is a picture of a Volvo 5Lt V8 fitted with SS integrated exhaust/risers.
The two blue pipes in the image are the pipes that I am talking about.
You're talking abut two the blue hoses, not pipes.... correct?

in this image they go to the two inlets to the SS manifolds.
Yes! This is the "spent" seawater path.
Whether the engine is raw water cooled or a Half CCS is installed, this path would be the same.

On my current engine they go to the CI exhaust manifolds.
When I fit the HE I intend to connect these pipes together via a "T" pipe and feed the water back to the HE.
Unless you're doing a Full System, this is "spent" seawater, and will enter and exit the exhaust system.
IOW, there is no returning water or coolant to the system from this location.

Be careful when you "T" or Split water flow.
Depending on which part of the system, this will require a "diverter style T or Y" ...... not a normal T fitting.


In the Volvo closed cooling system these outlet pipes from the thermostat housing do not exist.
Correct! The Raw Water cooled engine thermostat housing incorporates a mixing chamber.
This style cannot be used for a Closed Cooling System.
(see image below)

I saw an image of the "T" pipe somewhere in an arctical on cooling , I believe it related to a Mercruiser but the water ciruit must surely be much the same for both makes.
You'll find that there are similarities.

Does your kit not include all parts?
Click to expand...


Blue represents seawater.
Yellow represents mixed tempered water heading for the engine's Circulating pump.
Red represents water that has removed engine heat and then becomes mixed with incoming seawater headed for the exhaust system.

The closed cooling drawing is an example only.
 

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