re-engine. Does it (ever) make sense ?

[Boatbore]

I have a an old (1987) Riva Bravo which I keep and use in the South of France. She is a perfect boat for what we use her for and there is little that I would change about her general design and certainly the quality of the build is extraordinarily high. There is one catch....she has Cummins VT 555 engines, that were rebuilt by a previous owner (at vast expense ! - I mean really vast !)..... but they are smelly and smoky and very noisy. This was the engine that Cummins should never have made and they weigh over 1000kg each whilst producing (at very best) 320 hp. On a good day they will give her 32 knots abosulutely flat out, and she cruises at about 26 knots quite well when there are not too many people on board, but as soon as she is loaded up performance starts to drop off and i have even been knocked off the plane by a big wake....... So what to do ? My initial thought is that she is a good boat that suits me well, but that I want to go faster. We mostly do short trips (7 to 10 miles) in mostly flattish water and it would be great to be able to cruise at 30 kn or even a smidge over. So the logical thing is to sell her and get something else. I think I would get about £50,000 for her so would need to put say £100,000 on top if I was going to get something like a Windy Grand Bora which would give me that perfromance whilst still offerring the sort of massive cockpit and sunbathing space that I need. I would consdier other models but they need to be around the 40 ft mark (42 or 43 max) and they need to be quick whilst still being able to sit 8 people round a table for lunch (which rulesout all the "fast" boats like Huntons etc)...... But it did cross my mind that if I spend £100,000 on a massive engine upgrade and general refit I could make my existing boat perfect whilst still keeping my running costs low (The Riva is shaft driven and a joy to drive and to handle, plus she is cheap to maintain)...... of course the finished product would not be worth much more than £100,000 at best so it would be capital destructive but so would owing a £150,000 windy whereas the Riva doesnt or shouldnt depreciate much.
I havent got an engineer or a naval architect involved yet, but the Yanmar 480 hp six cylinder is smaller than my existing monsters, and weighs 640 kg each vs the 1023 kg each of the old ones. This means I would probably need to add some weight amidships but I could do that with ballast or perhaps an extra fuel tank. The extra HP should give me a top speed of nearly 40kn so I could cruise comfortably int he low 30's where the boat handles brilliantly...... Gearboxes would have to change but there is a good chance that the shafts and sterngear could stay (they are massively built)......not sure.
I know that I am mad (we all are otherwise we wouldnt own a boat at all) but am i completely mad....or just a little bit mad ? All thoughts, views and experiences welcome.

BB

 

[neale]

Financially, almost certainly not. But there are other reasons to re-engine and IMHO it can makes sense for those other reasons, putting aside the actual cost. I re-engined a boat and don't regret it for one second despite the fact that when I sold the boat about 5 years later I only got for it what the new engine had cost me.

 

[Boatbore]

thank you. That is more or less the logic that I am applying. When you re-engined, did you have to change anything structurally (i.e. were the new engines different size/weightto the old), and /or to the sterngear etc ? And if so, how easy was it to find someone sufficeintly competent to do that part of the job really well ?

 

[MapisM]

am i completely mad....or just a little bit mad ?

The latter, imho.
I mean, repowering the Riva is definitely a capital destructive option, as you aptly called it. But pleasure boating as a whole is just that, 'innit?
If you are sure that the Bravo (with her rather poor space optimization, by today standards) suits your needs, you can't get a much better new hull regardless of price.

Just two thoughts/suggestions:

1) Extra tanks are always nice to have, but if for any reason you couldn't fit them, I would think more than twice before adding any useless ballast to a boat like that.
I don't think her planing attitude would be much affected by the lower weight, even if slightly unbalanced. If anything, my bet is that it would actually improve.

2) Re. the engine, if he doesn't pop up in this thread, pm Latestarter and listen carefully to his suggestions.
Aside from the fact that he can give you a sound advice on repowering in general, I'm pretty sure he had some accurate views (both very positive and very negative, depending on their versions) on the Yanmars.
If you go that route, you definitely don't want to put another couple of potential future problems in your engine room.

Good luck, and keep us posted!
It sounds like an interesting project indeed.

 

[PCUK]

Is money at the top of your boating priority list or enjoyment. If the former then no, if the latter then yes and enjoy your perfect boat. I'm just about to re-engine a 1978 Reinell with a new engine and drive and can't wait to get on with it. When the time comes to sell the boat you will find it much easier to sell as it will have the advantage of the modern engines and you'll almost certainly recover what you spent.

 

[Nautorius]

My smaller Sunseeker was re-engine in 2009. Whilst it does not make great financial sense (for the guy who did it) I bought it because of this. I have the Classic boat I love with the benefit of a new engine. If you are keeping her then it can make sense, but first look around at what you could buy and be sure if you do not want any of the alternatives. Then search for Riva Bravo's that have been re-engine like this one: http://www.yachtworld.co.uk/boats/1988/Riva-Bravo-38-Special-2612918/Spain#.UyhheFVwa70

this has 2007 Cummins in it.

 

[Boatbore]

Thanks a lot for these views. It sounds like we're all roughly on the same page.

And thanks Nautorious for that link. This boat is very similar to mine in terms of general good condition and it is interesting to see the re-engine, although I think he has gone for that model so as to save on gearbox and stern gear (prob even props)....... he might have a point in fact !! I wanted to get a lot more HP, but in fact it might be smarter to follow his lead. I need to speak to engineers etc.... I will keep you all posted !

 

[Spi D]

Not a lot to add re. money and value. Re-powering will keep her out of the water for some time, adding the cost of keeping her on the hard + lifts.

Less weight will improve speed and mpg performance a lot. 800 kg less will be noticeable when accelerating, I'm sure.

 

[Bandit]

I have repowered two of my boats with new engines and my business does a lot of repowers.

What is your boat made of GRP or wood?

If you changed the engines what other work would you want to do at the time?

You could fit a pair of Volvo Penta D6 with a gear box for 700kg per side, in 330 hp, 370 hp or 435 hp, unless you need the extra range I would not fit an additional fuel tank.

The additional hp and the combined weight reduction would transform the performance as would the better acceleration.

However don't underestimate the other work you would need to do as well as fit the engines it all mounts up, then add the while I am doing this the wife wants a new galley, new head linings, refit the saloon, new cushions etc etc.

If your boat is running well and you are considering changing it for a newer model now is the time to do it.

However if you truly love the boat and you yourself keeping it for at least 10 years, repower and get the benefits from it.

What displacement is the boat ?

 

[Latestarter1]

I have a an old (1987) Riva Bravo which I keep and use in the South of France. She is a perfect boat for what we use her for and there is little that I would change about her general design and certainly the quality of the build is extraordinarily high. There is one catch....she has Cummins VT 555 engines, that were rebuilt by a previous owner (at vast expense ! - I mean really vast !)..... but they are smelly and smoky and very noisy. This was the engine that Cummins should never have made and they weigh over 1000kg each whilst producing (at very best) 320 hp. On a good day they will give her 32 knots abosulutely flat out, and she cruises at about 26 knots quite well when there are not too many people on board, but as soon as she is loaded up performance starts to drop off and i have even been knocked off the plane by a big wake....... So what to do ? My initial thought is that she is a good boat that suits me well, but that I want to go faster. We mostly do short trips (7 to 10 miles) in mostly flattish water and it would be great to be able to cruise at 30 kn or even a smidge over. So the logical thing is to sell her and get something else. I think I would get about £50,000 for her so would need to put say £100,000 on top if I was going to get something like a Windy Grand Bora which would give me that perfromance whilst still offerring the sort of massive cockpit and sunbathing space that I need. I would consdier other models but they need to be around the 40 ft mark (42 or 43 max) and they need to be quick whilst still being able to sit 8 people round a table for lunch (which rulesout all the "fast" boats like Huntons etc)...... But it did cross my mind that if I spend £100,000 on a massive engine upgrade and general refit I could make my existing boat perfect whilst still keeping my running costs low (The Riva is shaft driven and a joy to drive and to handle, plus she is cheap to maintain)...... of course the finished product would not be worth much more than £100,000 at best so it would be capital destructive but so would owing a £150,000 windy whereas the Riva doesnt or shouldnt depreciate much.
I havent got an engineer or a naval architect involved yet, but the Yanmar 480 hp six cylinder is smaller than my existing monsters, and weighs 640 kg each vs the 1023 kg each of the old ones. This means I would probably need to add some weight amidships but I could do that with ballast or perhaps an extra fuel tank. The extra HP should give me a top speed of nearly 40kn so I could cruise comfortably int he low 30's where the boat handles brilliantly...... Gearboxes would have to change but there is a good chance that the shafts and sterngear could stay (they are massively built)......not sure.
I know that I am mad (we all are otherwise we wouldnt own a boat at all) but am i completely mad....or just a little bit mad ? All thoughts, views and experiences welcome.

BB

Yep I agree, Cummins Triple Nickel noisy smokey heavy old monstrosity.

For gawd sake do not be tempted to replace with Yanmar 6LYA3 480,now out of production and has been a complete disaster.Cummins QSB 6.7 blows the doors off the old LYA3 and very little difference in price.

 

[Robg71]

plenty of second hand motors around if you look, or even supposedly reconditioned (factory new) cummins to be had for a lot less than new prices.

 

[Boatbore]

Some really helpful advice here. A pair of reconditioned bigger HP engines would go a long way to making the cost a bit more sensible. I will investigate further.
In terms of other questions. The boat is GRP, And very solidly built. She displaces about 8 to 8.5 tonnes..... She doesn't need a lot of other refit work, she is already in very good condition. For me the only niggle is the engines and her current performance otherwise she really is perfect for the job.

 

[MapisM]

For gawd sake do not be tempted to replace with Yanmar 6LYA3 480,now out of production and has been a complete disaster.

LS, am I right in remembering that in the past you also mentioned an older version of the same block, with a different injection system, which is instead very good and reliable?
That's the reason why I said "both very positive and very negative" in my previous post, but I might be mistaken....

 

[Latestarter1]

LS, am I right in remembering that in the past you also mentioned an older version of the same block, with a different injection system, which is instead very good and reliable?
That's the reason why I said "both very positive and very negative" in my previous post, but I might be mistaken....

Older 6LYA2 420/440 was best engine in this displacement/power node, quiet, refined, compact. Downsides, in the event of even a small overheat the parent bore block has to be scrapped. White smoke on start up. All this aside NOBODY could touch the LYA2 package.

Tier 3 came along and everything changed, the LYA3 was typical of a low volume engine approach. Similar block set up to LYA2, but now with new cylinder head, half baked mechanical dumb pump with electronic governing, engine still white smoked for a pastime on start up and should you hit an issue recon pump only available from distributor at huge $$! Another issue was black smoke, the AFC control is not automatic and has to be set up by dealer with electronic service tool at more $$ a visit. Owners have experienced rocket ship performance but black transoms and in efforts to solve the problem engine has been turned into an unresponsive slug, very difficult to find happy medium.

Sales of LYA3 fell well below predictions and Yanmar were unable to fund planned common rail replacement at Tier 3. Engine was marinised in U.S and production ended there last quarter of 2013. Plenty of engines in stock at dealers around the world being sold at big discounts. LYA2 parts prices are indecent, LYA3 are complete madness.

 

[dustywings]

I also have a Riva Bravo and have done what you are considering! I decided on a Bravo and looked at several all with the 555's then ended up buying one in Ibiza that had the Riva Crusader petrol engines as the price meant that I could repower it. I agree that if you are going for new engines then it simply doesn't stack up however I do my boating on a budget and bought a second hand pair of engines that had done 600 hours and been very well looked after. I did the majority of work myself but the finished result has been superb. The saving in weight over your engines was around 750kgs in total so I have a pair of 300hp engines which mean I cruise at 2000 rpm giving 23 knots and use 66 lph, top speed is 34 knots.

I went from this:

To this:

To this:

Very happy to discuss in any detail about my work and good to hear there is another Bravo owner on the forum!

 

[Latestarter1]

Nice neat installation, can see that down angle boxes worked a treat.

Using second hand Sabre 300's was very cost effective however in the longer term how do view impact on vessels resale potential.

I am currently helping owner in Holland who has prohibition notice on his Sabre 300 for environmental pollution due to white smoke and fuel sheen on start up.

Please please do not view as criticism of a nice job, but not 100% sure where this takes you........

 

[dustywings]

Nice neat installation, can see that down angle boxes worked a treat.

Using second hand Sabre 300's was very cost effective however in the longer term how do view impact on vessels resale potential.

I am currently helping owner in Holland who has prohibition notice on his Sabre 300 for environmental pollution due to white smoke and fuel sheen on start up.

Please please do not view as criticism of a nice job, but not 100% sure where this takes you........

I took the view that the resale value would be lower than if I had used a more modern (and expensive) unit, but the value is also much higher than when it had the V8 7.4l enigines which were, to quote Mr Clarkson, thirstier than Ireland! As I said I do my boating on a very small budget and this way I have a boat that I can afford to run which even with the sabres cost me far less than the diesel version of the bravo. I actually sold the old riva petrol engines to an enthusiast from belgium for more than the diesels cost me. I am afraid I also have a soft spot for sabres having grown up with a pair of 210's in my parent's Ranger 36. I totally take your point and of course you are right but this suits my circumstances and the project was really enjoyable as well!

 

[Latestarter1]

Thanks, all makes sense, get some heat shields on those Holset turbine housings and could be worth another knot!

Good luck.

 

[MapisM]

ended up buying one in Ibiza that had the Riva Crusader petrol engines as the price meant that I could repower it.

Whoa, I almost can hear the sound of those lovely 454 big blocks just by looking at your pic!
Were you planning to build up a LOT of cruising hours, and/or were those engines completely knackered?
For the typical yearly usage of a boat like the Bravo, I for one would have considered saving whatever you spent in repowering and keep burning petrol!
Btw, did you scrap them? Since they were also the original Acquarama engines, sometimes you can find people willing to pay decent money for them....

 

[Latestarter1]

Whoa, I almost can hear the sound of those lovely 454 big blocks just by looking at your pic!
Were you planning to build up a LOT of cruising hours, and/or were those engines completely knackered?
For the typical yearly usage of a boat like the Bravo, I for one would have considered saving whatever you spent in repowering and keep burning petrol!
Btw, did you scrap them? Since they were also the original Acquarama engines, sometimes you can find people willing to pay decent money for them....

Said it before..........Gasoline is for girls!

Question for Dustywings. Riva did a decent job getting some height into the exhaust system can we see how you configured the risers to achieve the same end, on the face of it fast running out of under deck space.