KAD42 over heating problems with photos

[Restoration man]

Hi all I've got sealine 360 statesman on shafts with kad42's been trying sort out a minor over heat on one engine for a couple of years now , only over heats when going flat out this needs to be done for at least 3 mins then temp starts to rise if pull sticks back it goes back to normal and won't over heat agin until flat out , this will eventually set alarm off but again only when flat out and never looses any coolant the temps show the same on flybridge and inside .i do get a bit white ish steam coming out of both engine when under way and planing , not sure if it's my paranoia but both look like this white steam might be getting a little worse but not sure , this over heat is not to much of a problem as I don't run flat out very often because of the cost of the fuel but I want it sorted was going to salcome last year in some big swells and could have done with the extra power but was to worried to push sticks further just incase it over heated not a problem in the soIentn but could been problem miles from land across lime bay !!!!
I did cure it a couple of years ago by rid lime the heat exchanger but it's back again ,this time I've taken the heat exc off and done it properly and cleaned out the oil cooler and checked all pipes for blockages but it still behaves as above , I've also changed the impellers no change and swop the jabsco pumps over still no better so a last ditch effort I've pulled the turbo elbow off as you can see it's rusted up out of the 10 holes in it 4 are completely blocked, 3are particularly blocked and 3 are clear ,could thus be the problem ??? The pictures do make it look worse than it is imho ,
so hear are my questions

1) could this cause my over heat ?
2)should I try drill out the rust and clean it out
3)or should I buy new ?
4) if buying new is genuine the only way toward ?or is after market ok ?I've found some from repower marine U.K. For £200 each ,I think I'm going to do both and change the exhaust rubber pipes as well it as an absolute pig to get off needed to take the silencer off so no chance of doing it when it's in the water the boat is Southampton based but i live in midlands took apart back end last year when weather picks up I will be back down gain to finish the job

thanks Nick

 

[[2068]]

From the pictures, I would say that yes, that could definitely be the cause of an overheating problem at high revs.
If it were my boat, I would replace them, as the housing doesn't look to be in great shape any more.
I have no experience of Repower Marine products, but if you could negotiate 10% off from somewhere, a Volvo elbow would be £245.

 

[alt]

Try Prior Diesel I find their prices and communication excellent

 

[volvopaul]

It would be the first thing I’d look at and the easiest to examine , I’d say your there . You can poke the holes out then dunk it in a bucket of neat brick cleaner for 24 hours will help .

 

[volvopaul]

Looking at the pic your 50% blocked so the sea water wouldn’t flow quickly enough to disperse the heat inside the heat exchanger, it’s a wonder you have not melted your rubber exhaust hose.

 

[kashurst]

time for new elbows I think. Even if you clean them out you need to check very carefully the other end where it mates with the turbo. If that end starts leaking it will not do your turbo any good. Probably worth a rydlyme treatment or preferably strip the entire cooling system then you know its all good.

 

[Restoration man]

It would be the first thing I’d look at and the easiest to examine , I’d say your there . You can poke the holes out then dunk it in a bucket of neat brick cleaner for 24 hours will help .

Thanks paul I will have a go at cleaning first and will post picks when done

 

[[2068]]

Thanks paul I will have a go at cleaning first and will post picks when done

The result could be some green flakes of paint floating on the surface and a bucket full of metal pieces the size of marbles gently bubbling away underneath, but it's worth a try to see what happens .

 

[Restoration man]

Hi all thought I should check back in a let you know how it went , I know loads of people start these
Threads but never says if it fixed it , well success ??all is well no over heat at all , in the end I bought 2 brand new
Elbows as Didn't want to end up doing the job twice , and Volvo paul you were corecet the exhausts had started to melt so I've also changed the rubber exhausts, even though the longer one was a total bitch to do , a bit like wrestling with a rubber alligator here's the latest pics oh and I didn't bother painting them Volvo green seeing as you can't see them so just used black smoth rite anyway thanks Volvo paul and everyone else who replied

 

[[2068]]

Make a note in the diary to replace them in another 20 years time
Good result.