Sea trial KAD32

If you're staying with a similar size boat Ian, there are single engined diesel options. Mine has a single 200hp engine that will cruise at sea 16-18 knots doing about 3MPG. Very quiet and equally happy chugging around the rivers at 6knots.

I know it is down to personal choice and there good reasons for going single but the boats I am looking at are mid 90's and with older engines I feel a lot more secure knowing I have 2 of them.

At least now we have all the cats amongst the pigeons, Petrol v diesel & twin or single, lol
 
Our petrol boat has 2, 18 year old 4.3 V6 petrols that are still sweet as anything, it probably doesn't have that many hours on it but I would put that down as another benefit of buying petrol.

We don't put that many sea miles on it as it spends 70 % of its time on the river but it is just as happy at sea, where we get around 1 1/4 miles to the gallon and spend between 50 and 75 hours running at a cruise of 22 knots each year.

Both our petrol boats have been 100% reliable and especially with an older (1993) boat the knowledge that should the worst happen I don't need to sell my house to replace an engine has been very comforting.

Range and availability of fuel are the downsides for serious sea work plus as the hours mount at speed its loss of efficiency against diesel would mean it would get expensive to run but for our use I would say it is actually cheaper to run and certainly to maintain and on the rivers I enjoy quiet, smoke free, vibration free running without the worry that I am glazing the bores and safe in the knowledge that I am spending virtually the same on fuel as any 400 hp boat.

As I said we are in the process of trying to buy a diesel boat, I just hope that it will be as reliable and cheap to run as the petrol boats have been. the only thing I won't miss will be the jerry cans.

If you think your petrols are cheap to run, you are in for a nice suprise if/when you buy diesels.

We only have the one engine which is a 2003 KAD32. We spend about the same amount of time as you (70%) just plodding along on rivers (or even canals!!) with the rest of the time spenty blasting around on the bigger tidal rivers. We are taking her to sea this year as well.

Anyway our average mpg over the whole of last year was 5mpg. We did on one weeks trip to Loughborough (which was mainly canal work at tickover) pull 7.5mpg. We thought at one point the fuel gauge had packed up. And remember also that the price per gallon for red diesel is considerably cheaper than the current price per gallon of petrol. This is a small boat though (S23) with one engine.

Our diesel engine has been super reliable thus far and gives us no cause for concern.
 
It is not just the fuel I am talking about, it is the overall cost of ownership over the time we have had them. maybe we have just been lucky but friends with similar aged diesel engines have had far more problems and spent a lot more on keeping them running. We have no Turbo, No supercharger, no injectors, no expensive pumps, and none of those silly electronics. Basically we have very little to go wrong, and 2 engines that should they go wrong you can lift out with 1 hand, yet they still turn out more HP than friends diesels with all the gizmos.
On the river (Broads) we only run 1 engine and get about 5 mpg (6 litres an hour)

Petrol comes from Asda in Jerry cans so we pay about a 10p per litre premium over riverside red.

Would never argue that a petrol boat is better for high percentage sea work but apart from fetching the fuel in cans I do believe it to be a better option for the use we have had to date.

Diesel owners may be lucky enough to get through their ownership without having to replace a turbo, super charger, injectors, pumps or other expensive kit but the reality is anything mechanical will eventually break and as such have to be factored into the hourly running cost, with petrols you have less bits and with exception to starter and alternators (spark protected) virtually everything else is a fraction of the cost of diesel bits.

You may also find that your fuel consumption is considerably higher at sea than it is on tidal rivers, even if you are running the same speed.

I really do hope your right and I am going to find that my overall costs come down but evidence based on friends costs, including one with Kad32's is that my wallet will be emptier at the end of the year than it is at the moment. Where I distribute it and how often will vary but it all comes from the same pot.
 
I think most of you are getting carried away with the petrol/diesel thing. The O/P is asking about a £30K, 25'-26' boat with a single KAD32 vs a single petrol V8. He won't be using it as a caravan, going to Anglesey or doing 300+ hours a year (I doubt you will find many 5 year old, 25' sportscruisers with 1500+ hours on).
Realistically he will probably be doing 50-100 hours a year (which is probably still above average for that type of boat) and not all of it will be flat out.
In this situation there's not much to choose between petrol and diesel. I chose petrol for my 26' boat and it was absolutely the right choice for me.
 
I think most of you are getting carried away with the petrol/diesel thing. The O/P is asking about a £30K, 25'-26' boat with a single KAD32 vs a single petrol V8. He won't be using it as a caravan, going to Anglesey or doing 300+ hours a year (I doubt you will find many 5 year old, 25' sportscruisers with 1500+ hours on).
Realistically he will probably be doing 50-100 hours a year (which is probably still above average for that type of boat) and not all of it will be flat out.
In this situation there's not much to choose between petrol and diesel. I chose petrol for my 26' boat and it was absolutely the right choice for me.

50-100 hours may as well be a caravan!!!!

If caravans are your thing but you want a floating one then yes petrol may well be a better choice, however for those who want a boat diesel has to be the preferred choice. If only for the avaliablity of the fuel waterside.

We are working on the 1500 hours target. Ours had 240 hours when we bought it at 5 years old, now coming up for 7 after 20 months of owning her, she has 600 hours, hoping to reach 1000 before the year is out!!!! No point owning a boat if all it does is stay moored to its home berth.
 
50-100 hours may as well be a caravan!!!!

If caravans are your thing but you want a floating one then yes petrol may well be a better choice, however for those who want a boat diesel has to be the preferred choice. If only for the avaliablity of the fuel waterside.

We are working on the 1500 hours target. Ours had 240 hours when we bought it at 5 years old, now coming up for 7 after 20 months of owning her, she has 600 hours, hoping to reach 1000 before the year is out!!!! No point owning a boat if all it does is stay moored to its home berth.

You do love caravans:-).

On the south coast petrol is available everywhere mate.
 
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If you are looking at real boat engines, by that I mean huge, heavy, low revving, normally aspirated diesels or with low pressure turbo's, then they will last for ever if they are given the odd oil change.

Today's high pressure turbo'd, supercharged, high revving, lightweight diesels will be lucky to last as long as a petrol engine and have a design life of 1000 hrs with 10% tickover, 20 % flat out and 70% cruise. yes they may last twice as long if you are lucky but they are not going to go to the dizzy heights of the traditional boat diesel. They now have more electronics on them than a petrol engine and although the engines may be reliable the sensors aren't.

boats should be chosen on their intended use, for a small sports cruiser the light weight and high HP per litre of petrol improves the balance and results in better performance and handling. if you want to use it as a serious cruiser and cover high mileage then diesels will be cheaper to run.

Unfortunately there is a school of thought that if it is a boat it must have diesels, in the same way as all boats should have sails or should be made of wood and that will impact on the ability to be able to resell easily at the right price.

From my own perspective that allows me to negotiate a price that is way below what the boat is worth and at sale time price it at a level that makes the boat easy to sell but if I was buying something newer then it would have a small high revving diesel, like kad 32's. they are about as close to a petrol as you can get. I would not hold on to it for to long though and get rid before the serious bills started to come in.
 
Been on both sides of the petrol/diesel debate, we owned a single petrol powered sealine 240, mercruiser 4.3, before that a Bayliner ciera again with a 4.3 mercruiser, in our experience both were nothing but trouble, had to replace the engine on the bayliner after the head gasket went and sold the sealine after many thousands trying to keep her running, and we always had them maintained and serviced as required.
Both engines were around the 10yr old mark, predominantly salt water cooled but for the odd trip inland on rivers.

We now have 2 Kad32's, I dont want to tempt fate but they have been faultless for 3 seasons, where as both petrols were constantly letting us down, we have more confidence with them where as the petrols used to hold us back, our current boat was re-engined from petrol to diesel, both petrols had done 600hrs before requiring major expense on rebuilds.

Personally for hassle free boating it has to be diesel everytime, petrols are less expensive but require higher maintenance which results in higher bills over an extended period of time, if you are good with a spanner then thats fine but how many want to be buried in the engine bay when the sun is shinning when all you want is a relaxing vacation.
Been there and got the oily T-shirt to prove it.

So if faced with a choice petrol or diesel, diesel for reliability and resale value, petrol for more boat for the money, but dont spend too much as the value quickly erodes away in fuel cost and maintenance.
 
I think most of you are getting carried away with the petrol/diesel thing. The O/P is asking about a £30K, 25'-26' boat with a single KAD32 vs a single petrol V8. He won't be using it as a caravan, going to Anglesey or doing 300+ hours a year (I doubt you will find many 5 year old, 25' sportscruisers with 1500+ hours on).
Realistically he will probably be doing 50-100 hours a year (which is probably still above average for that type of boat) and not all of it will be flat out.
In this situation there's not much to choose between petrol and diesel. I chose petrol for my 26' boat and it was absolutely the right choice for me.

Nice call.......;-)
 
Interesting how comparisons are being twisted here. Comparing old V8's with no electronics to modern, ECU managed diesels is hardly fair. My boat is a 2003 and has a Nanni 200hp diesel fitted to it. The engine is based on the bullet proof Toyota LandCruiser engine. It has no fancy electronics, no supercharger, no unreliable sensors etc and i wouldn't hardly call MAX RPM of 3,600 high revving. She'll cruise all day at 3,200 RPM @ 25lt an hour and 16-18 knots. Servicing costs peanuts, basically all it needs is oil and filters and the odd impeller.

A diesel engine like this, or an old petrol, no contest. A diesel engine like this or a modern petrol with all the electronic ECU's, i don't think so.
 
Interesting how comparisons are being twisted here. Comparing old V8's with no electronics to modern, ECU managed diesels is hardly fair. My boat is a 2003 and has a Nanni 200hp diesel fitted to it. The engine is based on the bullet proof Toyota LandCruiser engine. It has no fancy electronics, no supercharger, no unreliable sensors etc and i wouldn't hardly call MAX RPM of 3,600 high revving. She'll cruise all day at 3,200 RPM @ 25lt an hour and 16-18 knots. Servicing costs peanuts, basically all it needs is oil and filters and the odd impeller.

A diesel engine like this, or an old petrol, no contest. A diesel engine like this or a modern petrol with all the electronic ECU's, i don't think so.

To be fair the KAD32 has bugger all in the way of electrics and ECU's. The basic engine before all the extras are bolted on is as crude a diesel as they come. The forced induction produces the higher power output. Servicing is not expensive as long as you know where to go and where to get the parts from.
 
To be fair the KAD32 has bugger all in the way of electrics and ECU's. The basic engine before all the extras are bolted on is as crude a diesel as they come. The forced induction produces the higher power output. Servicing is not expensive as long as you know where to go and where to get the parts from.

Yup, that was my point. The petrol v diesel comparisons are comparing old tech petrols against new tech diesels, rather than like for like. There is no more to go wrong with an old tech diesel, such as yours or mine, than there is the old tech V8 petrols, maybe even less.
 
Yup, that was my point. The petrol v diesel comparisons are comparing old tech petrols against new tech diesels, rather than like for like. There is no more to go wrong with an old tech diesel, such as yours or mine, than there is the old tech V8 petrols, maybe even less.

Sorry, misread the post. Crossed wires and all that!!!
 
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