470 Alternator Conversion, Couple of Questions

[cheaperts]

So, all the posts and discussions of catastrophic failure of the 470 charging system have me proactively replacing mine with an alternator. I have a 1 wire marine Deloc type alternator a buddy gave me, and I'm going to fashion brackets for it, here are my questions:

1. I see the breezeworks kits and others use the bolts on the water pump cover/timing cover, but I'm seeing 2 good sized bolts in the end of the head that only appear to be holding the coolant overflow basket, I was thinking it looked like better attachment points, steel head verses aluminum block, larger bolts. Is there a reason I shouldn't use these?

2. The coolant overflow tank will be displaced if I do the above, I have room in front of the engine in the bilge/doghouse, would it be acceptable to mount it down low, about even with the crank, on the engine mount decking? Does it really serve that much of a purpose or should I just scrap it all together? I've never understood how coolant will flow back into the engine if the system is pressurized.....

 

[RogersJetboat454]

Re: 470 Alternator Conversion, Couple of Questions

Question 1 I'll leave to the 470 experts.

2. The coolant overflow tank will be displaced if I do the above, I have room in front of the engine in the bilge/doghouse, would it be acceptable to mount it down low, about even with the crank, on the engine mount decking? Does it really serve that much of a purpose or should I just scrap it all together?

Yes, you need a coolant overflow tank.
You could perhaps get away with mounting it lower, but the reason it is mounted up high is because gravity is on its side in that position, and there is less likely to be voids or air pockets.

I've never understood how coolant will flow back into the engine if the system is pressurized

Simple physics. Yes the coolant becomes pressurized as the engine/coolant heats up and expands. If the pressure becomes greater then what the radiator cap is rated for, the coolant gets forced past the cap and into the overflow bottle. When you shut off the engine, the engine/coolant cools down and by the laws of physics contracts. Since the coolant volume essentially becomes smaller, it creates a void in the cooling system. The pressure in this void is less then atmospheric pressure. Atmospheric pressure pushes down on the coolant in the overflow tank and forces it back into the engine until the atmospheric pressure, and the pressure in the engine are relatively equal. If you look at your standard radiator cap, you will see a silver disk on the business end of the cap. This disk opens inward when there is pressure against the back side of it allowing the coolant to return to the engine.

 

[cheaperts]

Re: 470 Alternator Conversion, Couple of Questions

I knew it had to be simple enough, haven't ever studied a cap enough I guess. I can mount it elsewhere and keep it up high, just much easier/roomier down there.

 

[stonyloam]

Re: 470 Alternator Conversion, Couple of Questions

Yes you can relocate the coolant tank. Mine was relocated to the transom. Try to locate it at the same height as the original mounting. Here is a photo of my Breezeworks setup:.

 

[cheaperts]

Re: 470 Alternator Conversion, Couple of Questions

I don't have power steering so I'm envisioning the alternator basically where your pump is, and I'm thinking I could arrange a stand or bracket to put the tank up at that level but still infront of the engine, the back half of mine and the transom is very tough to get to, plus I like the idea of it up fornt where I can see the level and condition of the coolant

 

[fmalott]

Re: 470 Alternator Conversion, Couple of Questions

I don't have power steering so I'm envisioning the alternator basically where your pump is, and I'm thinking I could arrange a stand or bracket to put the tank up at that level but still infront of the engine, the back half of mine and the transom is very tough to get to, plus I like the idea of it up fornt where I can see the level and condition of the coolant

stonyloam gave you a picture of the conversion with power steering i found a picture of my conversion without power steering hope the picture is ok. i did the conversion myself with the help from this site it was very easy