Cat C32's running at least 5 deg warmer

Having mine cleaned knocked 8 /9 degrees off and. It cost euro 800 so not so bad to be honest.
Note to self: plan a cruise to the Baldricks when the boat will need the next heat exchangers cleaning! :eek:

What did they do exactly, if I may ask?
Normally you should have three heat exchangers each side:
- water/water
- water/air
- water/oil for g/boxes
And in some cases, also water/oil in the engine...
 
Removed a few hoses and circulated acid for about an hour a side. There were plenty of splutters as it disolved and cleared. To be honest the total time was 3hours ( so e150 of labour ) and probably e50 of acid or e5 if he bought it from the local supermarket (e1 per litre ) so he did well out of the deal!
 
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My c32s now 4.5 yrs old and c650hrs show 80 degrees on the gauges from the day they were brand new till now, and whether P, D summer or winter. I'm just back from a big cruise in 27deg seawater and they showed 80deg throughout. I'm therefore surprised to hear all these stories of differing temperature readings in different conditions.

And yes I have freshwater flushers to all heat exchangers. Both engines and gearboxes, both gensets, and the airco system. Easy job and I'm surprised it isn't much more common. If I'm leaving the boat more than 2 weeks I flush.

Also allows me to run genset in shipyard

On my next boat I think I'll hard plumb this, with electric valves and a panel full of LEDs, so I can do it from helm almost automatically.

I think I'm going to get a quote for installing a fresh water flushing / pickling system as you've done JFM - I think that a while back you sent me details of how you completed the mod so I'll dig that out and see what my man in Marina D'Arechi says! Amazing that you've put on the same hours as me and are still running consistently around the 80 deg mark - something's definitely amiss with my cooling.
 
I can also confirm that cleaning the exchangers Does work. As part of the rebuilt did the four port engine exchangers the proper way. Dismantle the lot, clean every single pipe in them, renew o-rings, refit.
Was a Lot of work, Never bothered with the stbrd one.
Result is that stbrd engine runs 3-5 degrees hoter than Port one. May do the redlyme bodge job on stbrd this winter and compare...

V.
 
Ok folks, I took this opportunity to give Imgbox a try, as a Photobucket replacement. Let's see how it goes...
Thanks in advance for confirming whether the three pics are visible at your end or not.

They are meant as a comparison with those from Deleted User above.
Not same engine (mine are mechanical V8, his are common rail V12), but similar MAN stuff anyway.
The first two exchangers below are the aftercooler and engine cooling respectively.
The third pic is of the g/box exchanger, just for the records. Not sure if Deleted User had his cleaned, but they are very different anyway.

TGfDMwSG.jpg


00Mr2DKs.jpg


jx8drsY8.jpg
 
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They look Ok to me -sorry to say hope I,am wrong P

With the top one the after cooler you can see the tide mark where the sea water drains down to -even that's clean .

There are other reasons for raised coolant temps if you exclude the obvious caked up coolers

Thermostate (s) packing up,--- not opening --- temps ok doing slow ,they a safety hole that a bit through ,but temps rise going fast cos the Dia of the hole is small and the stat s not opening as it should .

Slipping belt(s)
Impeller wear
Restricted through the hull fitting
Restrictions in the strainer(s)
Partial pipe collapse
Blockage s in the block channels
Worn impeller of the closed circuit
Restriction of the entry into the exhaust .

You will get an improvement cleaning those but they are no where near as cruded up as Deleted User,s

Well @ least you not running round with the guages on 100 and have started the process of remedy.
Btw MAN alarms @ 94/95 well my book says so
Scania is 105
 
Okay, didn't know that the gearboxes also had heat exchangers, thanks for the info!
I didnt say your gearboxes would have coolers, I just said they might!
 
Not sure if Deleted User had his cleaned, but they are very different anyway.
Yes my gearbox coolers were cleaned too. Btw I went from Photobucket to Picture Push a couple of years ago. Works well enough for me
 
They look Ok to me
...
Yep L, I agree that the coolers were nowhere near as dirty as I expected, particularly if you consider their age+running hours.
In a sense, we should think that the more they run, the better (the boat used to be run very frequently and with 200 or so hours/year, during the last 4 years).

Ref. the other possibilities you mention:
- I'm not sure to understand slipping belts: the raw water pumps are gear driven (and they were controlled anyway), what else of the belt driven stuff do you think could affect the cooling system?
- Impeller wear can be ruled out, as they were just replaced (btw, the old ones weren't bad at all).
- restricted flow is an option, but only theoretically, because a) the boat vas launched not long ago, with all the bottom checked/cleaned, and b) a similar restriction on both hull fittings is unlikely to say the least. Anyway, while I sure have no wish to dive inside the marina, I'll try to have a look when we go out for the sea trial.
- strainers are fine (and pretty much oversized, btw).
- pipe collapse: none visible, and again, it would be very unlikely that such fault affects both engines in the same way.
- "block channels", wazzat?
- worn impeller in the closed circuit: that's an interesting point. Have you ever heard of the need to make any maintenance to the internal pump (which as I understand is made in bronze)? According to my MAN guy, they last forever. Besides, again, how unlikely is it to have both engines affected at the same time...?
- restriction to exhaust discharge: naah, it's built like a tank, I don't think so. And yet again, why both sides? Though I must say that in principle I liked better the above w/l exhaust exit of my old lady, where you could check the flow visually, but heyho!

Ref. the alarm bulbs, which are separate from the gauge senders, according to their plate they should go off at 93°C - and never did...
 
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Page 13 a bit generic but a list to work down if applicable
https://marinedieselbasics.com/wp-c...D2866-LE-401-402-403-405-D2876-LE-301-403.pdf

How hot we're you getting recently ,with the 14 degree inc in sea temp .?
Mine settle @ 84 when I use it .Sea temp varies + or - 10 from May to Oct here I think ?

Bit like peteM with belt tension and Altenator issues forgive me for asking but ----
You have checked the coolant levels in the header tanks ?

Sea water pump is indeed gear driven ,I think the closed circuit is belt driven -top centre pully .

Blocked channels are the passages in the block ,between the cylinders etc ,the closed circuit % of antifreeze is important and ideally should be changed every 3 y or so ,as it ages and goes off and then you get a coating inside the channels of the engine block ,it can be all flushed out .
Worse still there are two geneic brands of antifreeze and if you mix em ,there's a way a sludge forms and blocks up passages .
So next Q -- have you topped up coolant and if so did you check it was the correct stuff. - 50-50 chance .

Btw the Achilles heal of MAN --which is kinda coolant related

[Sorry Medmillo for the Thread Drift ]

is the two expansion cap rubber seals
The rubber with the compression and heat cycle developers a "set " --looses it seal gradually .
So being a conscious owner doing your Dailey checks etc ,by opening to check the tank level -you are actually edging nearer a overheat by compromising the refit and seal .Don,t ask how I found out ps!
MAN --cop out by saying replace every 2 years .
Big ones €60. Small ones € 40
Carry spares ---- Tip as a tempory measure use a supermarket carrier bag to get a propper seal .
Without a seal the coolant will escape when hot and the level drop etc .
My boat has "expansion tank pressure " guage so alarms off .Not sure on your "mechanical " variant .
 
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