PERKINS 6.354M mainfold/heatexchanger

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Depending on condition converting the Manicooler to engine coolant is not that hard just a change of plumbing . Just done mine ! Requires reaming out the tap in the water pump and drilling the inspection plate at the rear of the engine...

Can you explain the new cooling flows in this arrangement?

The conversions I've see would result in higher than nominal operating or exhaust temperatures at at least some mode, e.g. idle, low rpm, high load, etc, depending upon the flow.

The heat exchanger in the bowman hasthe capacity to remove a certain amount of heat. The raw water going through the manifold had a certain capacity to remove heat. If one removes the raw water cooling of the manifold, and doesn't add any cooling, e.g. another heat exchanger, there is less cooling capacity, right? Unless the theory is that there is plenty of excess originally, that loss of cooling should show up as more heat somewhere, sometimes.

I'm also curious about things like the thermostat and bypass.
 
Can you explain the new cooling flows in this arrangement?

The conversions I've see would result in higher than nominal operating or exhaust temperatures at at least some mode, e.g. idle, low rpm, high load, etc, depending upon the flow.

The heat exchanger in the bowman hasthe capacity to remove a certain amount of heat. The raw water going through the manifold had a certain capacity to remove heat. If one removes the raw water cooling of the manifold, and doesn't add any cooling, e.g. another heat exchanger, there is less cooling capacity, right? Unless the theory is that there is plenty of excess originally, that loss of cooling should show up as more heat somewhere, sometimes.

I'm also curious about things like the thermostat and bypass.


Well yes the Hx has more capacity than it needs . The thermostat has never been fitted in my engine for the last 15 years ! My cruising speed is 1300rpm so what little extra heat is put into the system makes no difference. I also think there is less load on the raw water pump as it doesn't have to push the extra 4-5 liters of water so it has better flow over the Hx. I know a few people that have done this and its OK on the normal engines but not the turbo's and most of all it gives peace of mind.
 
Well yes the Hx has more capacity than it needs . The thermostat has never been fitted in my engine for the last 15 years ! My cruising speed is 1300rpm so what little extra heat is put into the system makes no difference. I also think there is less load on the raw water pump as it doesn't have to push the extra 4-5 liters of water so it has better flow over the Hx. I know a few people that have done this and its OK on the normal engines but not the turbo's and most of all it gives peace of mind.

Okay. Interesting. Thanks!

I guess this is a different strokes for different folks thing.

It doesn't matter to me much in Florida, but in colder climates, I'd want the thermostat to help with warm up. I also like the headroom in the cooling system so it is less brittle if some zinc bits get stuck, or there is some buildup. And, I can't wrap my brain around the impact of the reduced seawater loop volume on the flow rate.

1300rpm is a very modest cruising speed. Way lower than
I run my present 6.345(M)s or previously ran my 6.354MGTs. The turbos on the MGTs didn't even kick in, really, until 1500rpm and didn't do much until 1800rpm. I run my 6.354(M)s at 2100, a little less than 80% of their WOT under load.

At any rate, to my understanding, the adjustment you made won't work on the original configuration.

And, to my knowledge, the body of the Bowman Manicooler isn't made of steel. It is made of a very expensive corrosion resistant, low-copper aluminum alloy, LM6M (The tubes are a cupric-nickel alloy). So, with the Bowmans, I wouldn't expect corrosion to be a problem, even after many years of service, anyway. I guess I don't see much upside.

For me, personally, I guess am still happy with the system.as designed. But, like I said, different strokes for different folks.
 
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Okay. Interesting. Thanks!

I guess this is a different strokes for different folks thing.

It doesn't matter to me much in Florida, but in colder climates, I'd want the thermostat to help with warm up. I also like the headroom in the cooling system so it is less brittle if some zinc bits get stuck, or there is some buildup. And, I can't wrap my brain around the impact of the reduced seawater loop volume on the flow rate.

1300rpm is a very modest cruising speed. Way lower than
I run my present 6.345(M)s or previously ran my 6.354MGTs. The turbos on the MGTs didn't even kick in, really, until 1500rpm and didn't do much until 1800rpm. I run my 6.354(M)s at 2100, a little less than 80% of their WOT under load.

At any rate, to my understanding, the adjustment you made won't work on the original configuration.

And, to my knowledge, the body of the Bowman Manicooler isn't made of steel. It is made of a very expensive corrosion resistant, low-copper aluminum alloy, LM6M (The tubes are a cupric-nickel alloy). So, with the Bowmans, I wouldn't expect corrosion to be a problem, even after many years of service, anyway. I guess I don't see much upside.

For me, personally, I guess am still happy with the system.as designed. But, like I said, different strokes for different folks.
The system as designed was the only big mistake Perkins ever did IMHO Seawater sent through a cast iron manifold has a very finite life !
 

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The system as designed was the only big mistake Perkins ever did IMHO Seawater sent through a cast iron manifold has a very finite life !

Hey Steve63,

I'm with you on that one. I keep pondering why they did it as they did. The only thing I can come up with is that they figured manifolds would be cheap and available and/or back in the day the alloys of steel and aluminum were unavailable or super expensive, so they decided just to view the manifolds as a scheduled replacement parts instead of adding a second cooler or more complex plumbing and the associated expense. Dunno'. Don't like!

But, like I said, I think the alloy used in the aluminum alloy in the Bowman Manicooler should do much better for much longer than the old carbon steel. At the least, this Bowman Manicooler owner is hoping so! :)
 
Hey Steve63,

I'm with you on that one. I keep pondering why they did it as they did. The only thing I can come up with is that they figured manifolds would be cheap and available and/or back in the day the alloys of steel and aluminum were unavailable or super expensive, so they decided just to view the manifolds as a scheduled replacement parts instead of adding a second cooler or more complex plumbing and the associated expense. Dunno'. Don't like!

But, like I said, I think the alloy used in the aluminum alloy in the Bowman Manicooler should do much better for much longer than the old carbon steel. At the least, this Bowman Manicooler owner is hoping so! :)
I did consider the bowman conversion but It would be major surgery for me and would have to relocate 2nd Alt etc etc so as the manicooler cleaned up ok we will stick with the present mod.
 
I just got word from Marine Exhaust Systems / MESA in Alabama that they are building the first pair of mani/multi coolers!!! This is great news for us Perkins Perkins ST.63544M folks!
 
I just got word from Marine Exhaust Systems / MESA in Alabama that they are building the first pair of mani/multi coolers!!! This is great news for us Perkins Perkins ST.63544M folks!

Agree great news. There is a need out there.
 
Thanks but what about inhibitor fluid, anodes, life cycle of o rings and end caps?
By inhibitor fluid I presume you mean coolant ! change it if you think so. The unit is a very good alloy so the anode is optional. Keeping a couple of spare rubber caps is probably a good idea ! O rings are cheap. I find the average life of end caps on NL gensets is about 10 years. Coolant about a 1000 hours.
 
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