coolant conversion

[joshua.sides]

Is it possible to convert a new 170 engine from Mercruiser to a closed coolant system because it seems that they do not sell them that way. I currently have a mercruiser 170 with a closed sytem and would like to keep that system because I jump from salt to fresh and back often and would like to save a bit of money by using the old closed system and would like to know if it would work on a new engine. I am grateful for any ideas and thoughts on this subject. Thanks.

 

[Boomyal]

Re: coolant conversion

if it worked on your old 170, why wouldn't it work on the replacement 170? No doubt, closed cooling is better. Not only does it prevent corrosion, it allows your to run a thermostat that is better suited to the internal combustion engine.

 

[stonyloam]

Re: coolant conversion

If you are talking about a 3.7 L, 470 type Mercruiser engine, you must use the closed cooling system. You just got a long block, right? Just transfer the parts from the old engine to the new. Good luck.

 

[joshua.sides]

Re: coolant conversion

Unfortunately mercury marine does not offer the 3.7 anymore and only a 3.0l turn key which the specs say that it is an open cooling setup. Also the plans show the intake manifold on the opposite side as my engine, which is where my coolant tank sits. So I suppose my next question would be if I do swap it all over are there parts available to complete the conversion, i.e. brackets.

 

[wire2]

Re: coolant conversion

If you can't find or make the required brackets/fittings, go to any millwright shop, show them what you're doing. They will make custom parts for you and make it work.

 

[telstar1]

Re: coolant conversion

Not much if any 470 closed cooling system components will work on the 3 litre. Totally different engine.You should be able to purchase a made for 3.0 litre closed cooling kit (such as the MC301 from Go to Marine made by San Juan Engineering) for somewhere around $600.
In theory at least the actual heat exchanger unit from the 470 would likely have ample cooling capacity to cool a smaller 3 litre engine. Mounting it and routing of hoses could be a challenge.Look at the kit.

 

[stonyloam]

Re: coolant conversion

Unfortunately mercury marine does not offer the 3.7 anymore and only a 3.0l turn key which the specs say that it is an open cooling setup. Also the plans show the intake manifold on the opposite side as my engine, which is where my coolant tank sits. So I suppose my next question would be if I do swap it all over are there parts available to complete the conversion, i.e. brackets.

try Breezeworks for a longblock http://www.breezeworks.net/ or this http://cgi.ebay.com/ebaymotors/MERC...9443537QQptZBoatQ5fPartsQ5fAccessoriesQ5fGear Would drop right in. Another 470, either complete used or rebuilt longblock would be a direct drop in. Using a 3.0 L would probably involve some significant changes, and also a gear change in the outdrive. Good luck.

 

[joshua.sides]

Re: coolant conversion

Thanks for the help everyone I looked at the links and I went ahead and just purchased a fresh block, so I can just swap the accesories. I also just picked up another raven 21' cuddy but it has no engine or drive can anyone suggest a larger engine that will fit since I won't have to change any gears I can just use a new outdrive, please keep in mind the same boat with original motor and full fuel weighs approx 5,000 lbs. Again I greatly appreciate all the help and if anyone would like to know how the builds are coming just send a message and I will get back as soon as I can.