57hrs, Corrosion Issues, Transom Plate Replaced

Yes! A source for Raw Water will still be required as well. It's really time for you to do some Homework by Googling the various Terms we are discussing. The Internet is a great place to understand things that are new to us. If you intend to own this boat for a long time I'd suggest a Closed Cooling System with a Water Scoop installation. Al W.
 
67vetteal said:
Yes! A source for Raw Water will still be required as well. It's really time for you to do some Homework by Googling the various Terms we are discussing. The Internet is a great place to understand things that are new to us. If you intend to own this boat for a long time I'd suggest a Closed Cooling System with a Water Scoop installation. Al W.
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Oh sorry I thought this forum was for helping each other so I called it fresh water instead of closed cooling system, but you knew what I meant but instead of just answer the questions you'd rather be a dick about it.

Sure I could go google everything and the internet is a wonderful place but the point of this board is to help each other which you were doing fine until this last post.

I was going to ask why a closed cooling system still needs a water pickup but I guess that's to cool the closed water what's the point of closed if you are still using saltwater?

Guess I will go google how not to ask questions on a board that's meant to ask questions.
 
Here you go a nice google search and oh wow look they call it Fresh Water Cooled imagin that!

The Truth Behind Fresh Water Cooling Systems

The term "Fresh Water Cooling Systems" also known as "Closed Marine Cooling Systems" can be confusing as these systems circulate antifreeze and not water. Marine Fresh Water Cooling systems are similar to the cooling system in an automobile, however, rather than a radiator they utilize a heat exchanger and rather than using air to remove the heat generated by the engine they use lake or ocean water. The heat exchangers are constructed by inserting a tube bundle of small tubes, maybe 150 or more, into a single large tube approximately 4" - 6" in diameter. The raw water pump on the engine flows sea water through the inside of the smaller tubes and makes multiple passes back and forth across the unit while removing the heat from the engine before finally exiting and flowing out the exhaust system. The anti-freeze or "jacket water" flows up and down across the outside of the smaller tubes in one single pass as it dispels the heat load of the engine into the raw water. Select the following link to see a diagram of a typical Half System... These systems are thought to be primarily reserved for people who operate in corrosive water conditions, however as you will see these systems have much more to offer than just corrosion protection. One of the main deficiencies of the standard "open" cooling systems is that they rely on a pressure balance for proper functioning. In extreme cases you can be introducing 40 degree water into the circulation loop that is attempting to regulate the engine at 160 degrees. This makes it near impossible for the engine to operate without some amount of cycling. Also with the onset of more stringent emissions regulations it is near impossible for the open systems to produce a stable enough operating condition that the engine spark and fuel mapping can be maximized.

So if the point of a closed cooling system is to help with getting rid of corrosion but you still need the sea water to cool the heat exchanger what keeps the heat exchanger from corroding do you now have to flush it instead of the engine?

Oh forgot Dick Head want's me to google everything instead of ask here. Back to Google I go.
 
Morpheus said:
Here you go a nice google search and oh wow look they call it Fresh Water Cooled imagin that!

.....
Oh forgot Dick Head want's me to google everything instead of ask here. Back to Google I go.
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:lol::smt043:lol:
Tell us how you really feel:thumbsup:
:lol::smt043:lol:
 
I'm still shocked to learn this is a common problem with BIII drives. Are Alphas also prone to this?
 
I use Google all the Time as a great place to do Research on unknown Topics. There was no intent to cause Slight or Criticism. My abilities to adequately describe any given Topic as a Hunt and Peck Typist are the reason for the Google suggestion. If you read back threw this Thread you will come across my Volunteering to describe in further detail and that I would Monitor this Thread to be of additional assistance if possible. I know our Boats can make us angry but please refrain from adverse comments about this Forum and it's members.

Now, if we can return to your problem all our Time has been well spent! What is the latest? And FYI, Heat Exchangers are not necessarily Prone to a need for regular Flushing. They are made of Brass which holds up very well in most if not all Waters. Many Boats that are not Trailered never see a Flush and they hold up well. Dick Head Al:huh:
 
comsnark said:
I'm still shocked to learn this is a common problem with BIII drives. Are Alphas also prone to this?
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My experience is only with B-III Outdrives. And I am really surprised that Mercruiser is still using this method of Thru Transom Water Pick Up. A Rubber Hose held in place by a Friction Bushing. It is a wonder that an Engineer liked this design and a Supervisor signed off on it even though it is known to be Problematic. On Top of that they are very hard to service for a repair of this item if it is a smaller size Vessel. :smt013 Al W.
 
Well, I have an Alpha drive (actually 2) that lives in salt. I *think* I have this very type of connection (i.e. I know I have a pump in the drive unit, and that water passes through a connection that looks very much like the one on this Bravo drive). The boat is older. . but was kept on a lift for more than half it's life. The drives are pulled every year, and there is no hint of corrosion at this point. (we have looked specifically at this)
 
Now that you've gone back to helping and not telling me to go goggle everything I take my comment back.

Basically where things are at is they replaced the plate and say they have hopefully sealed up arond the hose better.

My biggest fear is in 1 or 2 years time or in another 100hrs I'm going to be faced with the same problem again. So now I'm wondering if I should go with the scoop method for raw water or go ahead and put a closed system in even if the costs are high it could potentially save me 4k in repairs in the future.
 
When I bought my boat, I considered the FWC conversion. Two mechanics gave seriously price quotes (several boat units) and stated for engines which had a few hundred hours on them that the benefits weren't worth the cost.

For what it is worth.
 
Yea I've read that but I'm still under 100hrs (pretty close to 100 now) so I think I'm still in the safe zone and installing FWC even it if costs 4k is better then paying that every couple of years to replace the transom plate.
 
I just finished installing a fresh water cooling system on my boat. I went with the full system. Cost was around $1000 and one afternoon of my time.
Note that the fresh water cooling system and your transom issue are totally unrelated things
 
Woody said:
Do you have the parts manual for your drive? Did you see this corroded part? How about a pic?
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I do have the parts manual (I think) and I did not see the part so no picture but a couple of posts up there is a picture and I imagin it looks alot like that picture or maybe not as bad.

Cape Haze MM Did the service. They have given me no reason to not believe them so I'm going on what the Service Manager and the Tech that worked on it is telling me.
 
Westie said:
I just finished installing a fresh water cooling system on my boat. I went with the full system. Cost was around $1000 and one afternoon of my time.
Note that the fresh water cooling system and your transom issue are totally unrelated things
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I had a problem changing the oil which lead to all this discovery of the corrosion so I'm sure I couldn't install it myself.

And now that you have said they are unrelated I guess when you install this you still use the pickups on the drive and would still have the issue at the transom so whether I go closed or not doesn't make a difference it's all about getting rid of the potential of corrosion at this same location.
 
I have an Alpha drive, so I have to use the water pickup and pump in the drive unless I want to add a pump on the engine itself. There is quite a bit of difference in the water passage thru the transom on a Alpha and Bravo drive.

The reason I say the problem you are having and adding FWC are unrelated is that with raw water cooled and FWC you still have to get the raw water up into the cooling system some how, either via the drive water pickup or via a thru hull. It's after the water is past that point that the cooling systems differ.

I think if I were in your situation I would change the water pickup to a thru hull and add FWC.
 
Ok. . .remind me again. . . what is the difference between the half system and full system FWC replacement? The difference is if the manifolds are included in the closed loop. . right?

So. . .raw water through hull pickup . . . .eliminates corrossion at the transom plate. Also, for an alpha drive, you end up moving your "pickup pump" from the drive to inside the engine compartment. (I believe for a BIII drive, the pump is already on the engine. . .right?)

FWC Half system: Protects the cylinder block from raw water. Eliminates the inevitable "corrosion buildup and overheating" issue. In my area, I am told Raw water engines last about 16 years because of this issue.

FWC Full System: Protects the cylinder block and the manifolds from raw water. In addition to the benefits above, your manifolds are no longer replacement items. You still have to replace the elbows (and risers if you have them) every 3-5 years, as they still see raw sea water. So your $2500 job drops to . . . . $1800? (I am thinking it doesn't drop to half since I am not sure how different the labor cost is to take it 3/4 apart vs fully apart)

When I was being quoted, I can't fully remember, but I think I was seeing numbers in the $2500-$4000 range (per engine) for a FWC full system replacement. Now. . .how much is a block replacement?

I think on the 100hr boat. . FWC is a worthwhile job. I would have done it on my 300hr boat, except that I have long ago learned that if a mechanic recommends against a job. . . you don't want that mechanic doing the job. I couldn't find a mechanic that both recommended the job and offered a reasonable price.

As for the raw water pickup. . .I am still confused as to why this is an issue for BIII boats and not an issue for Alpha boats. Edit: Ah. . Westie says that the configuration is different at the transom plate. OK. I buy that. And yeah. . . based on this thread, doing both jobs doesn't sound like a bad idea.
 
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Morpheus said:
I do have the parts manual (I think) and I did not see the part so no picture but a couple of posts up there is a picture and I imagin it looks alot like that picture or maybe not as bad.

Cape Haze MM Did the service. They have given me no reason to not believe them so I'm going on what the Service Manager and the Tech that worked on it is telling me.
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I’m not suggesting that they’re pulling something on you or that they shouldn’t be trusted. I think that you would have benefited by seeing your problem area, which part and how bad. The reason I ask about the parts manual is for you to look at it and learn the correct names of parts. In post #51 you refer to the part as the transom plate, this is inside the boat. In an earlier post you said they changed the part on the outside, that’s called the gimbal housing. After looking at my boat with the drive all the way up and turned to the right I think that area is rinseable with a garden hose. I was able to get my finger all the way to where the hose bends and goes into the gimbal housing. I would probably make up a smaller dia end to screw on the hose so that it could shoot straight in there. You don’t have to call me a dick, my wife already did that this morning.
 
I'm just calling the parts what I was told by the Tech and the Service Manager so if I'm not using the correct names then Marine Max doesn't know what they are talking about.
 
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