Knackered KAD 42s

DoubleVision

DoubleVision

Well-Known Member
Joined
16 Nov 2006
Messages
781
Visit site
Time for engine replacement and accompanying huge expenditure. Volvo dont do a straight six that will fit my Sunseeker Martinique 36 without sinking it anymore (D6 and even D4 are far too heavy. Where have all the 43,44 and 300`s gone? I`d even settle for a pair of new 41`s. Any ideas anyone
 
Sorry to hear your news.

First, speak to 'Col' (posts here), I think he will be able to tell you if your 42's are knackered with a capital 'F'! He seems to be able to fix most Volvos and you can do a lot repairing before replacement is the only option.

A friend at Sparkes has a 'seeker Martinique 36 with 41's and recently looked into replacing engines, had a great offer available and was even offered to p/ex his 41's. (which are still ok)

I will probably see him this weekend and could get details for you or even PM you his phone number and you can talk directly.
 
The D4-260 could be a candidate. It's 660kg so 90kg per engine heavier, though.

Also consider the Mercruiser 4.2L ES 250, which comes in at only 588kg with a Bravo III drive which is much closer to what you currently have. Have a look HERE. You'd need an adaptor for the drive shield, as the cutout is smaller on the merc (I think).

dv.
 
Surely the best replacement is the Yamaha / Yanmar / Nanni 315hp Toyota based engine.

Roughly the same weight as your current lumps, only disadvantage (in some peoples' minds) is the lack of electronic management systems.

I think you are looking at £14k odd plus VAT per side for new engine and drive, bit more for the Yamaha.

The Yanmar and Nanni have Merc drives, which, as someone else said, have a smaller transom opening than the Volvo, but adaptor plates are available.

Good luck in your quest!
 
Go for the Merc D 320's, having installed dozens of Volvos and Mercs, I know which I'd buy, we run a 27 ft Artic Blue RIB with the D320 and it is a superb motor.
Remember the KAD 300 squeezes 285hp from a 3.6 block whereas the D 320 uses a 4.2 block.
Also the service costs on the 44 and 300 is much higher as there is much more work involved in adjusting the valves, the mercs have have hydraulic valves for years, so the servicing is very easy. Also they are a lighter unit than the Volvo 6's.
 
I agree go for the Mercruiser 4.2L D320

I have the Cummins-mercruiser D300 (slightly older version of the 4.2L D320)

These are now 2 years old and have been a pleasure to own.
Incredibly smooth
Almost smoke free even on start up
No black stern or sooty dinghy.
 
Isn't the problem with the mercs that they are very slow off the mark with little low rev torque where it's needed. Where as the Volvos with the supercharger and turbo have the torque all the way through the rev range?
 
Thanks for all your help guys. I will certainly look into the Mercruiser option. The Kads I have were rebuilt by the company mentioned by Ians not a year ago. they have done 90 hours and have oil pressures that are well below the manufacturers minimum,Starboard engine has a very nasty knock and after extensive work still over heats unless the thermostats are removed and the port (3rd rebuilt engine under warranty and has managed just 22 hours) is 400 revs shy of starboard engine with copious oil leaks and excessive crankcase pressure (smoke rings blowing from the oil filler cap). Maybe a rebuild could do the trick but can anyone recommend someone that can do the job right? Really appreciate your input guys.
 
[ QUOTE ]
Isn't the problem with the mercs that they are very slow off the mark with little low rev torque where it's needed. Where as the Volvos with the supercharger and turbo have the torque all the way through the rev range?

[/ QUOTE ]

Our Princess is a fair lump and manages to leap out the water.

I have tested in calm conditions on one engine

Max speed 11.5 knots
cruise speed 10 knots

Max tourque @ 2400 rpm
max revs 3950 rpm -/+ 25
Curv for 300 hp here with , 320 not far away but not to hand now.

Merc 300hp
http://www.cmdmarine.com/PDFs/18280303.pdf

Volvo 310hp

http://www.volvo.com/NR/rdonlyres/853A340D-6FB3-476A-86DD-2C4FBA7BAEAB/0/D6310_inboard.pdf
 
How are they 'knackered'
A good well cared for diesel, with regular oil changes, is not run in until 1000 hours and unlinkely to need even a top overhaul until 5000 hours.
Have they done high hours, been mistreated, or is there a problem that is fixable without the expense of replacement.
 
You must log in or register to reply here.

Share this page

Top