Heat exchanger for MerCruiser 350 MAG with ECT

[Chris Lovlecae]

I want to put a heat exchanger on my "new to me" 2011 Sundeck 260 before it hits the salt/brackish water for the first time next season. Mine came with the 350 MAG with the Emissions Control Technology. Prices for the Mercruiser banded FWC kit are around $4,000. Has anyone put a Mr. Cool kit (or other after market kit) on an ECT engine? I was planning on $2,000 for the kit when I saw the exhaust manifold and risers were a bit different on mine than what the aftermarket kits call for.

The boat will be kept on a lift or rack stored (haven't decided yet) but will not sit in the water longer than 4 days (long weekend) but I'm hoping a little preventative actions will stave off more expensive maintenance later on.

Engine only has 195 hours and has been freshwater kept up until now.

Thanks for any advice!

-Chris

 

[Stee6043]

Mr Cool makes great products but I'm not familiar with their full conversion kits. Good luck with your project either way!

 

[Chris Lovlecae]

Thanks! There's nothing on thier website that addresses my situation. Seeing as Mercruiser has been building 350s (and others) with the ECT stuff since 2008 I find it hard to believe there isn't an aftermarket system that will work that doesn't cost both an arm and a leg. I realize with boats most things cost at least an arm or a leg.

 

[Stee6043]

Thanks! There's nothing on thier website that addresses my situation. Seeing as Mercruiser has been building 350s (and others) with the ECT stuff since 2008 I find it hard to believe there isn't an aftermarket system that will work that doesn't cost both an arm and a leg. I realize with boats most things cost at least an arm or a leg.

I bet if you call them they'll know exactly what you need. They are super helpful...

 

[Chris Lovlecae]

Ugh. Just got an email response from Mr. Cool saying that Mercruiser is the only on that manufactures a closed loop coling system for the ECT motors. Mayby that's why I don't see posts about people adding these to thier boats. Seems like I could just get one from Mr. Cool amd make some modifications. I was hoping someone in this forum has tackled this problem before. I will post if I come up with something.

 

[Chris Lovlecae]

Whelp...I'm abandoning this plan. If I had a normal, non-EC engine then a cooling kit would be around $2,000. BUT because I have a EC engine with a catalytic converter, or something like it, then I need to buy the MerCruiser branded kit for $4,000 AND a new ECM for another $2k so $6,000 total for the conversion. Which, I know things are expensive but holy crap! It's about $2,300 for a manifold and elbow kit. I'm not sure how long the EC manifolds and elbows last but if it's 5-7 years then that same amount of money will almost buy me three sets of manifolds and risers lasting 15-20 years. Not sure I'll own the boat that long. Can the stock ECM be flashed with the new parameters and avoid an extra $2,000?

 

[Chris Lovlecae]

OK...to any that are considering a heat exchanger for a 350 MAG EC engine I have the following to post in the hopes that it will help someone. I emailed Mercury Marine to ask about the what I would need to purchase to add a heat exchanger to my engine. Here was their replay:

"The closed cooling kit for your 2011, 350 Mag MPI Bravo DTS EC engine is part number 879288A39 along with hose kit 879172A16. You will also need to replace your PCM with part number 8M0071885. When you purchase the closed cooling kit you will receive an exchange voucher for the PCM. You will not have to pay for the PCM if you turn in your old PCM along with the voucher to the authorized MerCruiser Dealer that you purchase the parts from."

Good news is the new PCM is free if you turn in your old one! Bad news is both kits together are $4,600 and change. Really missing those aftermarket kits from Mr. Cool.