Volvo TAMD63L vs Tamd63P

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Cymraeg

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Hi,

I've had an offer accepted on a Fairline 42 which was advertised as having TAMD63P engines fited - it now transpires that they are actually TAMD63L engines which, according to the specs., are have some 50hp less power each for similar fuel consumption, and almost 100 lb/ft less torque per engine. As a percentage this is about 13% less which I'm sure would be noticeable. The boat is otherwise immaculate and well presented for sale, but I am a little concerned over the performance that will be achievable, and the resale value if/when I should decide to change. What does everyone else think?

Thanks in advance...
 
Think I've answered my own question - got this off the Fairline owners club site:-

Engines: Tend to be 370hp Volvo TAMD63ps. These are an oldish design but excellent. They are slow revvers, max 2700rpm, and 2200rpm cruise, so quite different from the faster revving KAD series Volvos. Other engines fitted by Fairline were Caterpillars and the 63L version of the Volvos. The 63Ls were rated at 306hp and are pretty rare on the Phantom 40/42 - I would think they are quite inferior and should only be bought if there's a significant price discount


Would still be interested in other peoples experiences though. Thanks again.
 
The only thing I would say, is the rev range for the TAMD63P.

My 63P's will rev to 2800 with a clean bottom and props. I have rope cutters and strippers on my shafts, so I lose about 50 RPM, compared to what I had originally.

I would say the cruise revs should be 2400 to 2600 (depending on your max available revs), but I stand to be corrected!
 
I actually wrote that piece on the fairline website!

I had a ph42 with 63p. Lovely boat - had it 4 years, about 800 hrs, and it's still going strong (I'm in touch with current owner)

The 63L engine was very rare on the ph42 -I bet fairline did only single figures of ph42 builds with those engines, as most customers paid a bit extra and got 63p. I would think (based on my 63p experiences) the boat is underpowered with 63L, but ok if you're happy to cruise slow at 18kts say. But you'd want a pretty big price cut, cos it will be harder to sell later

Unless it is VERY cheap I'd drop it, and look for a 63p version. There are plenty of those around. Nice boat, good luck with getting one
 
Walk away unless the boat is way under the market price (like maybe £50k less). Generally speaking, you will have more difficulty selling any boat with the smallest engine option in the future and, in this case, the 63L is such a rare option on the P42 that it's a bit of an 'orphan' IMHO. Apart from financial considerations, the boat will be underpowered and I would think it would have a problem hitting 25kts clean and a lot less dirty so you will always feel dissatisfied with the boat's performance. Don't think either that you will get better fuel economy because you'll be revving the 63L's a lot nearer their max rpm to get a reasonable cruising speed. Both the 63L and the 63P are considered robust engines so reliability shouldn't be an issue with either
In the current market, there are so many nice boats with the right specs out there and that should still be available at good prices that there is no need to buy anything that isn't absolutely right.
Btw how did you find out about the engine? Was the owner/broker trying to hide the fact that they weren't 63P's?
 
Yup, that's sound advice

Often when you see a boat with the smaller engines it's 715 instead of 775hp, or 1360 instead of 1550, or suchlike. Pretty marginal. But 306 versus 370hp isn't marginal, esp on a 42 footer.

IIRC we got 30kts on a clean bottom with 63p. This dropped to 24kts with a dirty, end of season, bottom. The 306hp 63Ls might seriously struggle with a dirty bottom

Fuel ought to be the same. I mean, a 20kts cruise mpg ought to be the same with 63L and 63P. The 63L simply stops sooner, I mean the injectors dont add any more fuel once the 306hp level is reached. But at a cruise, 1900rpm say, when say 250hp is being developed, the fuel flow should be the same, more or less. In fact, the 63L might have finer pitch props, which could make it LESS economical in a cruise, kinda like driving car in 4th not 5th gear at 60mph...

So yeah, this is a much less desirable boat and will be hard to sell. Will be a perfectly ok deal, if £50k off the 63p price imho
 
Is it the one in Deganwy? nice looking boat but i think the white hull is also less desirable come resale time.
 
Yep, it's the one in Deganwy. Advertised as TAMD63P's originally and with a holding tank, both of which I wanted and both cock-ups on the spec. sheet. The advert has been updated (today) to show 63L's. Shame, it's a really nice boat and the broker and owner really efficient, decent people to deal with. The broker held his hands up today and admitted the error in his specifications before I shelled out on survey etc., so fair play to him there.

Thanks for all the comments so far - seems to confirm that it's a no-no.
 
Just seen the ad myself (28kts /forums/images/graemlins/smile.gif) and she seems to be the cheapest P42 on the market at the moment (correct me if I'm wrong). It's just a thought but it might be worth having a word with Volvo and asking what's involved in upgrading from 63L to 63P spec. My guess would be that it's not possible without huge cost. But another alternative would be to phone around a few Volvo dealers and see if somebody would do a p/x trading in the 63L's for new or recon 63P's. If you could get this boat for a low price and spend, say £30k on swapping the engines, you could end up with a P42 with 63P's at near their market value but you have the benefit of new or recon engines. This might also be a selling point when you came to sell
It's just a thought and it probably wont stack up financially but it may be worth a try before you walk away
 
[ QUOTE ]
the 63L might have finer pitch props, which could make it LESS economical in a cruise, kinda like driving car in 4th not 5th gear at 60mph...

[/ QUOTE ]Mmmm... Not sure about that, though common sense would say so. Let's see:
The same power is required to push the boat at say 20kts, with both the P and the L, 'cause there's no weight difference.
As a consequence, it's true that the L must spin faster than the P to produce the same power, thus the same speed.
And it's also true that the prop pitch is bound to be finer with the L.

But!

A quick look at the specs of both engines shows the following fuel consumptions:
63P: 248 g/kWh
63L: 235 g/kWh
Which means that the L burns less fuel than the P for a given output (=given speed).
And that's also reflected in the fuel consumption curves: at approximately 200 rpm MORE, the L burns slightly LESS than the P.

Of course I agree, otoh, that if the lower power option is so shabby to create problems like getting on the plane when the boat is loaded, or when dirty, then the boat is a lemon (and I have no idea if that's the case for the P42 with 63L).

But other than that, for real life usage I'd always go for the lower possible power rather than the other way round, even at the same weight.
Not to mention that normally (albeit not in this case) lower power means smaller engines, thus lower weight, thus further reducing consumption.
 
Just seen the ad. Nice boat but a few thoughts:

1. No way will it do 28kts!
2. Pity it's a 1998, not 1999 which had the new style saloon windows
3. The electronics are old and you might want to budget for new stuff
4. Irritatingly the owner has painted blue antifoul up to the chine. Why do people do that? I'd make a condition of the sale that he has it professionally removed back to a straight waterline
5. Holding tanks are generally easy to retrofit, say £5k max. It fits under the port-most bed in the starboard cabin, so the bed all has to be dismantled, but that's simple joinery
6. The worn out aft canvas can be easily/cheaply replaced www.flexicovers.co.uk
7. It's substnatially over priced, for a lemon, at £150k with those engines. Lemons are fine but they have to be cheap!
 
A few "Ah buts" Mapis...

"As a consequence, it's true that the L must spin faster than the P to produce the same power"

Only if the L produces less torque at the same rpm (I haven't looked at the data on volvopenta website)

"A quick look at the specs of both engines shows the following fuel consumptions:
63P: 248 g/kWh
63L: 235 g/kWh
Which means that the L burns less fuel than the P for a given output (=given speed)."

Only if the 248 and the 235 are measured at the same output. They must be measured at some given output, becuase the 248 and 235 figures are not constnats across the rpm range of the engine. If the P burns 248 at (say) 275hp and the L burns 235 at 275 hp, then yess the L is more economical (5%). But if the 248 and 235 are measured at (sa) 80% of max power, then you cannot make the comparison the way you are suggesting

The point I'm making is that if you took two identical boats with 63P and adjusted the throttle stop on one of them so that it only developed 250hp max, then at 250hp they would both have the same fuel burn!
 
[ QUOTE ]
And that's also reflected in the fuel consumption curves: at approximately 200 rpm MORE, the L burns slightly LESS than the P

[/ QUOTE ]

You can't say that for sure because the fuel consumption at any particular rpm will follow the prop demand curve for this boat/engine combination not the full power fuel consumption curve and, of course, we don't have the prop demand curves

I doubt whether there is any weight difference between the 63L and 63P. They have the same block and AFAIK the 63L is the down rated version designed more for heavier duty commercial use
 
Well, pardon me if I have a few "Ah buts buts"... /forums/images/graemlins/grin.gif

Yes, the L does produce less torque at any given rpm (looking at the specs & charts right now), but I don't see why that should be relevant at constant cruising speed?

Re. the specific consumption yes, the 248 and 235 are not perfectly valid throughout the whole range/load of course.
Those figures are usually measured at the max rated power. But according to more than one engine expert I spoke with, it's reasonably safe to assume that when an engine is more efficient at its rated power, it is also throughout the whole range, with only minor differences. Besides, that's the only figure we have... /forums/images/graemlins/smile.gif

Re. your last point, I'm not sure to have got it. Do you mean that the boat with the 63P with the throttle stop adjusted for 250hp max would burn as much as a 63L generating the same output?
If so, actually what VP specs says is exactly the opposite.
The curves are different throughout the whole range, and the "limited" 63P would simply not reach anymore its rated rpm/power, but I don't see why the fuel consumption should be affected (at any given output).
 
Yup, I can't say that for sure.
But that's the best we can say based on the available figures.
VP specs show also the prop demand curves btw, with the usual load factor, and the conclusion remains the same as in my previous post.
But I agree that those curves might (and most likely would!) be different for the boat we're talking about.
Again, that's just the best assumption we can do.

And no, there's no weight difference at all between L and P, did I say anything contrary to that?

PS: just in case, for Cymraeg or anyone else who might be interested: 63P vs. 63L
 
[ QUOTE ]
Yes, the L does produce less torque at any given rpm (looking at the specs & charts right now), but I don't see why that should be relevant at constant cruising speed?

[/ QUOTE ]

I was just commenting on your "As a consequence, it's true that the L must spin faster than the P to produce the same power" comment. That statement is only true if the L produces less torque, which you've now confirmed it does!

[ QUOTE ]
Re. the specific consumption yes, the 248 and 235 are not perfectly valid throughout the whole range/load of course.
Those figures are usually measured at the max rated power. But according to more than one engine expert I spoke with, it's reasonably safe to assume that when an engine is more efficient at its rated power, it is also throughout the whole range, with only minor differences. Besides, that's the only figure we have... /forums/images/graemlins/smile.gif

[/ QUOTE ]

Fair enough. But we're in the realm of "minor differneces" anyway. 248 and 235 are only 5% apart

[ QUOTE ]
Do you mean that the boat with the 63P with the throttle stop adjusted for 250hp max would burn as much as a 63L generating the same output?

[/ QUOTE ]

No I meant take 2 identical boats with identical 63P engines, then on one of them you adjust the governor stop/throttle cable so it has reduced travel, and so the engine max power is 250hp. In that case, at 250hp (or less) in both boats the mpg etc are identical. I was just trying to demonstrate that if the L is a restricted version of the P, there is no intrinsic reason why the L must burn fewer g/kw at the same power output. The differneces are more likely to be in propping, which ought to work in the P's favour becuase it is like 5th gear compared to 4th

I dont think we're disagreeing! And I just sent you a yahoo on seats
 
Well, I'm also looking at the engine spec.s, and there does indeed seem to be a weight difference between the 'L' and 'P':-

Dry weight:- 742kg (L), 754kg (P)
Torque (2800 rpm) :- 574 lb/ft (L), 667 lb/ft (P)
Fuel consumption:- 235g/kWh (L), 248g/kWh (P)

I had thought maybe it was possible to just swap the turbos and injectors to 'convert' a 'L' into a 'P'. Certainly the broker is telling me that this is the only difference - but then he's trying to sell a boat!
 
[ QUOTE ]
No I meant take 2 identical boats with identical 63P engines, then on one of them you adjust the governor stop/throttle cable...

[/ QUOTE ]Aha! Yes, I fully agree on that.
There must be more than that in the difference between P and L though, 'cause as I said the curves developments are pretty different throughout the range. Maybe the injectors and/or governor and/or turbo are different, 'dunno.
But it definitely doesn't look just like a "limited" P. In fact, apparently there was even (I wasn't aware of that before looking at the product bulletin) a medium duty 235hp version, whose curves are again different (and reported for 228 g/kWh).

On a side note, I'm still missing why you're considering torque and not power when cruising at constant speed...
...but at the end of the day yes, we're not disagreeing. Or maybe just very marginally.

Thanks for the email, I'm due for dinner right now, but I'll look at that as soon as I'll be back tonight.
 
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