Closed cooling

[Morgan's Cloud]

It seems like 95% of runabouts run on that mere 3%

It seems like you might need to travel a bit more

[MOP]

The water passages in the aluminum manifolds are brass lined, they were machined afterwards slightest nick or edge exposure it blows off real fast.

Added note engines run much better at higher temps, I have never understood why so many don't run 180 Tstats. I ran a 180 for many years with -0- issues!

[yeller]

Can anyone explain why a manufacturer of marine engines would use dissimilar metals in its construction , aluminum nonetheless , and NOT sell it as FWC only from the factory ?

(I've wondered this for a long time )

I used the same aluminum intake and exhaust on my 16 for 18yrs and most of the boating was in brackish water with probably 30% of the time in salt. I flushed after every use and there was absolutely no signs of corrosion. I don't think aluminum is the problem. It's the maintanence. Don't flush it after use and it will corrode.

[Morgan's Cloud]

I used the same aluminum intake and exhaust on my 16 for 18yrs and most of the boating was in brackish water with probably 30% of the time in salt. I flushed after every use and there was absolutely no signs of corrosion. I don't think aluminum is the problem. It's the maintanence. Don't flush it after use and it will corrode.

Certainly all 'fresh water ' isn't created equal , and it's amazing to read of some of the issues that some have experienced on different bodies of 'fresh' water.

I would expect that a large % of boats that are trailered to lakes and ponds are probably flushed out after use but at the root of my original remark was that the lion's share of all boats are not only in salt water but they stay over without haulout for all season or longer without flushing capabilities.

[Tidbart]

I used the same aluminum intake and exhaust on my 16 for 18yrs and most of the boating was in brackish water with probably 30% of the time in salt. I flushed after every use and there was absolutely no signs of corrosion. I don't think aluminum is the problem. It's the maintanence. Don't flush it after use and it will corrode.

Just to elaborate, Yeller, you are correct, the problem is the maintenance, or lack thereof. The salt got to my intake due to the fact that the previous owner never flushed it. He kept it in stack storage for 5 years and I doubt it was ever flushed, to my detriment. With that said, the intake will last a long time with the correct care. It will last a lot longer with closed cooling.

Bob

[smokediver]

I received and installed a Monitor closed cooling kit , block only. I decided to not pull the intake as there was no corrosion in the tstat housing and the area within the intake. I don't think monitor makes a distinction of wether or not it is a mag motor or not like other companies do. I had to pull my upper intake plenum to remove the brass fitting hidden underneath. It runs from the intake to port side pcv on the valve cover. The new water inlet with hose attached , made clearance an issue. I removed the fitting and ground it down , smoothed the edges , and was able to re install. Per the instructions I am using distilled water for coolant as the engine has seen salt water. I think it takes close to 5 gallons. After a month of running the boat and draining out the old water and adding new , I will add coolant.