Diesels - any use in a RIB

[Perryboy]

Just started looking for a RIB of my own and would like to know why most are fitted with petrol O/B. What are the pitfalls of having a diesel I/B. With petrol approaching £1/ltr why not swap to red diesel at 1/4 - 1/3 the price.
Any comments?

[John Kennett]

Diesel RIBs are great!

The main drawbacks are that you need a reasonably large RIB as the engine box takes up 3-4 feet of space, and the initial cost which is rather more than for an outboard powered boat.

Diesel RIBs tend not to have quite the same initial acceleration as petrol RIBs, but the pulling power when the turbo comes in is amazing!

While the difference in fuel prices remains (as I believe it will for some time), there is a good argument for diesel over petrol in the UK. Even if you never actually make up the difference in cost, paying thirty quid to fill up makes a weekend much more enjoyable than when you are paying hundreds!

John

[This message has been edited by John Kennett (edited 06 September 2000).]

[Allen]

John is quite right, diesel ribs are the business, but before taking the plunge you need to carefully consider what you intend using the rib for.

Over the years I have worked my way up to an 8.1 metre Scorpion with a 250 hp Yanmar diesel. This is a perfect cruising rib which lets me travel for less than a quarter of the fuel cost than I incurred with my previous boat - a 7.5 metre Scorpion with 175hp outboard.

There is a down side in so far as it is not quite as much fun playing in surf, and my access to some of the tighter coves around our coast is now restricted. The whole rig is heavier so if your towing there are trailer and vehicle aspects to consider also.

However the thrill of only having to pay for red diesel, for me, far outweighs anything else !

[tonyhill]

perryboy
Before you go spending large sums of cash on a diesel rib perhaps you would like to consider the outdrive leg. It is our experience that whilst engines have imprved dramaticaly over the past 10 years the legs have not and the further we dig into the topic the greater we are finding the problems. Have a look at my entry into the forum. We have people who have not listed in the forum but have many problems as we do. I have to admit that all are commercial operators but problems are developing/showing sign after only arond 150 hours of use. One company we are in communication with has been towed in 4 times this year, he has 1300 hours on his engine clock

tonyhill

[John Kennett]

There have been some problems with the 240hp Yamaha, but that seems to have been sorted by using a higher grade synthetic oil in the gearbox, and with the 300hp Yanmar/Bravo combination which has yet to be resolved.

You are unlikely to suffer outdrive problems with the 4 cylinder Yamaha (165 hp and 35 knots in a 7.5m RIB) or the Yanmar 250 with the Mercruiser leg (a bit faster!).

The problems do seem to be limited to the higher rated engines, as might be expected I suppose!

John