Turbo reconditioning

petem

petem

Well-Known Member
Joined
16 May 2001
Messages
19,103
Location
Cotswolds / Altea
www.fairlineownersclub.com
Yes on the KAD series inc my 300 ,s on my previous boat .
It’s the vane tips that burn out gradually increasing the clearance and loosing boost .
It’s caused by excessive EGT. Temporary perhaps due to overloading ,mid season s fouling , or too much K g,s or just basically a boat on the “ edge “ re power .
Or a combo of above .
Apparently the D6 turbo has a better construction - lasts longer / this is not an issue in D 6 powered boats or D9 ,D 12
Turbo failure for these if any ? Will be down to poor lubrication like any other turbo ,boat or car .

Symptoms for the KAD series are usually one engine when planning will stutter a bit ,not a lot.,just drop say from 3100 to 2800 for a few seconds ( boat speed drops a knot or two ) then it picks up .
At the start it may do it once a day .You conclude 8hit in the fuel or a brain fart from the ECU .
Then it happens more frequently for longer , perhaps even dropping speed wise from 28 knots ( typical P ) to say 20-22 Then picks up .Now you also notice it take s longer to do plane ,It’s still planes just takes longer .
Remember there could be a head wind ,bigger sea, wrong tab position , extra Kg more fouled props ,full tanks ,
Loads of other variables to mask the gradual wear .
Eventually the penny drops ,but only after as said ^^^ a period of “man “ denial :)

My mech wanted to send them off to be reconditioned, I sold the boat - it behaved itself @ the sea trial
He said ball park 5 years or 400 hrs ish .
A French equivalent of Volvo Paul .
Recon turbos and heat exchanger removal ,charge air removal and clean was quoted at € 5000 3 years ago .
I passed that on :) to the next owner .

Ps D3 I think has a variable vane turbo , it’s car tech a bit naughty of VPenta I think it’s got cam belts too ,another no no in a boat imho .
Prob with VV turbo s in a boat it the constant speed ,it increase the chance of them sticking esp at low loads .,never warmed up .
On your BMW , car or Volvo in this case you are changing the Rev s all the time ,
 
Last edited:
petem said:
I noticed on this thread http://www.ybw.com/forums/showthread.php?489574-Turbo-re-fitting-on-Volvo-penta-D3-A-A-early-2004 that the OP has had his Turbo reconditioned. What is people's experience of having turbos reconditioned? I've been told by our mechanic that he's never managed to get a satisfactory solution to repairing worn turbos and I suspect it's just a matter of time before ours need doing (KAD44's).
Click to expand...

The main problem with this model is the exhaust casting wears out causing loss of minimal clearance , this reduces to rpm of the turbo causing loss of boost pressure , a badly designed turbo . The 300 should have had a redesigned unit in my opinion.
 
As Paul says it’s not the tips that burn off on the kad engines it’s the exhaust housing that corrodes away. They can’t be reconditioned without fitting a new exhaust housing. To test if you need new turbos bring up the revs under load slowly until the superchargers just cut out and see if the revs stay the same. If the revs start to drop and the supercharger starts cycling on and off you need new turbos. Always replace the pair as they will both be about the same. Cleaning the props can make the problem go away for a bit but it will come back.
It mainly happens to boats with outdrives and is worse when the boat sits lower in the water as the sea water level is closer to the turbos.
It’s nothing to do with exhaust gas temperatures.
 
aquatom said:
It mainly happens to boats with outdrives and is worse when the boat sits lower in the water as the sea water level is closer to the turbos.
It’s nothing to do with exhaust gas temperatures.
Click to expand...

There’s plenty of images on the net of both . Google “KAD 300 turbo images “ picks up others like 42 44 .
Burnt tips of the turbine and corroded housings , of the KAD series turbos .
In my case the tips were burnt .quote was €800 for new turbine + bearings and a refurbed housing - each .

Any how the point is they are consumables for the KAD guys and need to be factored in to running costs every x years or Y hours ,
 
I've been though many KAD engines and NEVER had Turbo issues.

Does the fact that I boat in fresh water make a difference?
 
I’m no system analyst just the repair guy, but when you look at long term stern drive boat ownership in the Volvopenta camp your very much up against a brick wall.

A sterndrive boat gives better performance, better space per boat length, better economy of fuel, a more feeling your alive for the adrenaline junkies , all this compared to a shaft boat .

Add this then deduct, Drive corrosion, failing trim hoses, steering hoses, worn bushes and pins, higher servicing costs , corroding props, failing prop bushes, failing universal joints, failing steering rams, D4 D6 engine woes , corroding exhaust pipes, think my pen is running out now , rotten transom shields , water entering the hull laminate causing water ingress to the boat on old model boats , is it really worth it?

Yes it is you only live once.
 
petem said:
I suspect it's just a matter of time before ours need doing (KAD44's).
Click to expand...

Dont worry about it.
Best thing is keep using the boat regularly since not using it may lead to corrosion that may cause turbo wear .
 
I replaced my 2002 KAD 43 turbos with new although I’ve only done 400 hours. The exhaust housing looked quite corroded which is not surprising because it’s been living just a couple of feet above salt water for 15 years. Although a recon job may have worked I was worried about some of the horror stories on this forum and being in Spain I’ve got an extra hassle if things go wrong.
Two brand new Borg Warner’s were £1584 from Turbo Rebuild Ltd. No trade in of old units.
Very easy days work to replace both including coolant change while I was about it.
 
Last edited:
DavidJ said:
I replaced my 2002 KAD 43 turbos with new although I’ve only done 400 hours. The exhaust housing looked quite corroded which is not surprising because it’s been living just a couple of feet above salt water for 15 years. Although a recon job may have worked I was worried about some of the horror stories on this forum and being in Spain I’ve got an extra hassle if things go wrong.
Two brand new Borg Warner’s were £1584 from Turbo Rebuild Ltd. No trade in of old units.
Very easy days work to replace both including coolant change while I was about it.
Click to expand...

I guess that's not an OEM part? Any idea what other engines they do Turbo's for?
 
jrudge said:
I have no engine turbo issues that i know of, but i assume that the D12 715 hp turbo is the same one as fits a d12 truck ? They are US$500 odd on ebay!
Click to expand...

Big Hp difference ,would not have thought so .
It’s the casing on the KAD series , not cut out for marine environments.
Along with the elbow and horn or riser ,whole lot eventually corroded s .

Back to D 12 — run em hard - don,t listen to all this D speed long range stuff , get the EGT s up spec ,- nice as best burnt diesel with min deposits,of carbon products fouling the blades = longevity.
 
Penta D12 turbos have a watercooled jacket around the exhaust side, truck ones don’t.

A Volvo Penta D12 turbo is still cheaper than a Williams one though!
 
aquatom said:
Penta D12 turbos have a watercooled jacket around the exhaust side, truck ones don’t.

A Volvo Penta D12 turbo is still cheaper than a Williams one though!
Click to expand...


Joy

Having read about this I think the Williams issue is the waste gate sticking on open.

The williams team suggested taking the exhaust hose off and applying ( I cant remember what) to the vanes etc to clean them up.

Oven cleaner seems to do the same thing ( there are now 3 threads on Turbos running so I have no idea which one to answer!!) and is simpler to apply.

Other than that it is running fine so it does not seem too terminal.

Anyway I am sure Total have a shelf of Turbos looking for a home!

Jeremy
 
You must log in or register to reply here.

Share this page

Top