Re-engining (follow on from Callisto)

Dave_Snelson

Dave_Snelson

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16 Oct 2001
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Porthmadog / Port Leucate
www.makeyourowngarments.com
Hypothetically speaking at this stage (don't want to alarm SWMBO) I may consider a pair of diesels for CI as replacements for the current installation.

She currently sports a pair of V6 Vortecs at 205HP each, and I have no real need for the 46kts top speed that they deliver. They are in very good condition and as such they are saleable (dunno for how much though?).

So what engines would be suitable for driving a pair of 290 DP's with A9 props? I would be willing to look at 150HP each and 4 cyls intead of 6. I don't want to buy new (the boat isn't worth it) and would want re-conditioned.

So (hypothetically) what should I consider?
 
TAMD41's 200hp

TMD41's 150hp

Or AQAD coded engines

both 6 cyl. not sure if they would turn A9's though, i have seen A6's on TAMD and A5's on TMD, but CI must be a lot lighter than what i saw the engines in.

How much room have you got?
 
Why not speak to Mermaid Marine in Poole 01202 891824, they do factory rebuilt engines at sensible prices. Always very helpful, good company to deal with.
 
do you have DP drives at the moment?

what about 2.5 litre fords from transit, about 150hp (if i remember correctly) - if you dont have the room might be better to go for a '31 series engine, although 4 bangers are not as nice a 6!
 
Ive got the Ad 31's in mine twin 150hp and find them ideal for the boats size( 28ft) even though they are 4cyl they are still nice compact quite engines and cheep as chips to run....
 
Dave, just had a pair of KAD32P's fitted by coastal rides in my Targa 27, we took the AQ205's (V6) out and when I say not a lot of room left I mean not a lot of room left. If you need any measurements of the KAD32s let me know. It will also increase the weight at the stern and you will need to sort the water line if you go that route! On the uposide VERY good engines and quite ecconomical, we have done 10.5 hrs on both engines on less than 250 ltrs of diesel, will know exactly how much when we fill her up this week. PM if you want an idea of costs etc.
 
Dave, Your first prob could be gear ratio on the drives as the diesels rev lower. I was lucky and bought the whole lot as a complete package with matched engines and drives. I suspect your V6s top out at about 4400rpm (as Callisto's V8 did!) The diesels only rev to 3900. Some of this you could counteract with changing the pitch of the prop but not all of it so will not be running the boat efficiently.

Just to give you an idea, the AQ211 V8 I had was matched to a 290 SP with a ratio of 1.68:1 the AD31s are matched to 290 DP-A with a ratio of 2.3:1 Quite a difference.

The AD41 (200Hp) 6 potters would be matched to either SP at 1.61:1 or either of the following 1.78:1 or 1.95:1 DP if my book is to be trusted.

If you have DP's you may be OK but SP drives I have been advised can't handle the torque.

If you want performance, the KAD32 is the way to go or the new D3 if you have pots of cash to throw at it as you will probably have to buy a package with eng and drive cos I think they mostly use the new SX drive.

If not, look out for a pair of AD31Ps they are the 150HP units rather than the AD31L or earlier which are 130HP.

Nice thing with the 31's is they are so simple......no electronics....no supercharger and good old mechanical fuel pump etc. very little to go wrong. Sounds like a couple of tractors under there though so got to beef up the sound insulation.

If you are thinking Fords talk to TICO cos he did it.

PM me with a phone number if you want a chat about it.

Cheers

JH
 
Further to Callisto post, my 290DP drives are 1.95:1 ratio, fitted with B6 props and with crud antifoul was doing 28Knts at 3500rpm. The bottom has been totally cleaned and re-antifould so I would hope to see low 30's at wot 3900rpm.
The bobtail engines were fitted straight on to the drives and although we have lost a minimal amount of top speed thats without re-propping. Obviously the KAD32P's are now a bit rare or so I have been told so you may need to look at the other options listed?
 
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