Healthy temp on/at the exhaust elbow of a KAMD300 at 3100 rpm?

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I would have thought a little steam would be normal. Remember that water from a shower head steams well below 100c.
Agreed but this one is more than normal. Pic from yesterday with 24C airtemp.
IZSyl7r.jpg
 
Another thing, the engine tops out at 3650 rpm when it should be 3800, would that be an indication its running a too heavy ie pushing the EGT too high?
 
My Tamd41s top out around that which I believe is on the low side but my engines do not steam like that if it is any consolation.
 
KAMD 300s should be able to get a WOT rpm between 3700 and 3900 - so you are not far off. However that level of steam is remarkable even if the egt was high - which I doubt as your exhaust elbow temp seems pretty good and it's right next to the turbo. Assuming the engine temp is OK then I suspect there is just not enough water going through to cool the exhaust water and gas. Has the cooling system been cleaned checked completely?
I asked about silencers as my engine has silencers and exhaust that do not steam when the boat is moving on the plane at @ 3200 rpm. However If I do a fast stop and wait at idle -then the exhausts steam loads for about a minute - but the engine is just idling. I think the water in the silencers is very warm but the steam is overcome by a fast water flow. If you have a large silencer and low water flow maybe the water in the silencer is just getting hot and staying hot.
PS What is the sea temperature? The engine isn't loosing coolant is it?
 
Not enough water have been my assumption as well and I have replaced the oil cooler, new elbow, cleaned the intercooler mechanically and with acid, run acid through the heat exchanger and gearbox oil cooler. New impeller earlier this year and seawater pump checked a few years ago. Backflushed the seawater system in case there were something stuck in it. Freshwater side cleaned with acid 2 years ago, flushed 5 times a few weeks ago and circulation pump changed as the engine was loosing coolant making sure it was not a head gasket or crack problem (it was not, coolant is now stable and no water in the oil or oil in the coolant).

None of the above changed the steam problem and maybe dropped the engine temp a few degrees. IR temp reading on the thermostat housing reades 85C even though the instrument shows 90C.

Ok on the silencer and water temp was/is around 20C.
 
Chasing a "too much steam" problem and get around 45-50 celsius on the surface of the elbow. I have no reference and hoping some of you might be able to offer one?

I am thinking it's a bit hot, should be maybe 35-40 when the sea temp 19-20 celcius.
Hi there. I’ve twin kamd 300 in my ps32, They were blowing steam like a train. 500hts on engines. I removed all the coolers, had them professionally cleaned and reinstalled. Steam reduced by 90%. Still a small waft, but I think that’s normal enough.
 
Thx Clodagh and good to know you got it fixed. This is a 550h engine and one of the VP shops said they usually got the heatexanger out and sent it to a specialist.
 
I get a similar amount of steam as your above photo (hard to tell with photo). Pretty obvious we have an issue to resolve but the temps are all good and the engine sounds fine so it's a Winter job for me to examine in more detail. My suspicion is I've either got something trapped in the oil cooler or the hoses somewhere. You can rule out the elbow it seems but it's something I need to look at on ours.
I just try and not look behind me too much :)

Edit.. Tamd41a (the one with flaps in the elbow, which I've now fixed open)
 
Steam like this would not have been visible with underwater exhausts so this is probably more common than one might think.

I did the heat exchanger in situ with a Cable Push Puller Conduit Snake Cable this weekend and maybe 4 tubes were "stubborn" and on the first test drive it was ok ish wrt to steam but today it was not. I had the same after changing the oil cooler, ok ish at the first run but not at the second one.

Maybe something is stuck even though I've emptied the hoses when doing the oil cooler, intercooler and heat exchanger plus back flushing.

Next is the intake but probably need to wait until it's on the hard later this year not to risk breaking the hull seal.
 
Can you reverse flush?

Remove the impeller and replace the cover, decent sized bilge pump onto the exhaust elbow and pump a load of fresh backwards through the system and out through the hull fitting.

keep an eye in the strainer to see anything gets stuck on the outside of the basket
 
Yes you can and that's how. You might want to reverse flush each unit independently in-case "stuff" wont pass the next unit. Don't know if all the cooler pipes are the same diameter for example.
 
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