beta 20 or beta 25 -sadler29

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Scomber

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is the beta 25 over powered for a sadler 29 bilge keel ?
anyone fitted either of these engines who can offer comment please
also- new prop ? can anyone recommend a good folding prop that does the job ?
thamks in anticipation of your help
 
In reply it all depends on what you had fitted before, the shaft and the prop you want to use, and possibly the gearbox supplied with the Beta.
I dont think there are going to be great performance differences, nor indeed fuel consumption figures, but it might be worth looking at the performance curves for both engines, and specifically the torque curves, because you ideally need a good cruising speed set with the prop so that you get maximum torque with lower engine speed to reduce fuel consumption.
I replaced a Perkins 4108 (49BHP) with a Beta (35BHP) and find with the correct propellors, on both engines 15 x15 on the Perkins and 15 x9 on the Beta, that at 5 knots in still water the Perkins was running at 1300 rpm and the Beta at 1900 rpm.
The fuel consumption on the smaller engine is therefore not really reflected in the reduction in overall output in BHP.
If you have the engine changed professionally make sure that they fit and test a good antisiphon valve to ensure that if the water intake is left on, there is no possibility of seawater entering the lube oil in the sump via the exhaust elbow and head.
 
the 4108 is rated 48 hp @ around 4500 rpm i very much doubt your engine exceeded 3000rpm ( approx 38 hp ).
i took out my 4108 & fitted the Nanni 4150 HE rated 37.5 @ 3000 rpm i had to increase the pitch of the 18" MaxProp as the Nanni had more power @ 3000 rpm:D

i now get 2900 rpm full chat with a clean bottom with a boat spd 7.5 kts
 
The Beta is a great engine - are you considering any other makes too? ie:
Yanmar
Nanni (same Kubota engine)
Volvo D1-20 (has a very nice peak torque at low rpm)
Vetus (equivalent is only 2 cyl I believe)
 
What was your previous engine and how much power did you usually take from it? I have a BK Sadler 29 with an 18 bhp. VP2002 and seldom need to exceed 2200 rpm. which, from the fuel consumption, equates to about 7 bhp. [Using the old 20bhp.hr per gallon of diesel rule of thumb].
 
thanks for feedback

decided on beta for sure due to previous research and a friend who was more than pleased with performance service etc

old engine 20hp bukh-not sure how much rpm regularly used-no rev counter !!- but i do sometimes need to motor quite hard ie into swell

one of my concerns is that i dont want an engine in the boat if it isnt working hard enough
previously i've motored at 5.5 knts max thats always seemed comfortable

has anyone views on folding props that would suit a 28.5 ft boat with a beta 20 or 25

it's beginning to look as if the 20hp beta might operate at more suitable revs for what i need - but i would have to admit i'm a little bit in the dark still

thanks once again
 
I have a Beta 20 with 3 bladed prop. The boat is a Halmatic 30 - although the same length it is good bit heavier than the Sadler with a lot more under water profile. The engine pushes her along well without too many revs and also gives me plenty of power for handling so would be more than adequate for the Sadler. It is also very smooth which may be another consideration for you.
 
I re-engined my 27ft Westerly (replaced a Bukh DV20) with a Beta 25hp. I was told in posts on here that the 25hp is a later generation Beta than the 20hp, and it was also recommended over the 20hp by the local dealer.

I called Beta about the possibility that the higher hp would result in using the engine at lower revs than should be (this being bad for diesels according to conventional wisdom I had heard). My recollection is that they suggested that this is not necessarily the case with newer diesel engines. I don't think they gave me a definite recommendation either way, and I went with the local dealer recommendation of 25hp despite suspecting it too large.

I'm just back from a 3-week trip with plenty of motoring, some into head seas that would have seen me doing 3.5 knots with the Bukh + 2-blade prop. No problem making 5-6 knots at any time. It's probably overkill, but I was happy enough when trying to make port.

I'm very happy with the engine so far. In flat seas, 2,000 revs pushes me along very easily at around 5.5 - 6 knots I think. I rarely went over 2,600 revs even against a head wind.

I also changed the prop for a 3-bladed Kiwi folding prop which has good reviews and probably made a big difference in power - the boat seems to Sail faster too. I had some problems with corrosion on the prop parts in the first year (fixed/pars replaced @ minimal cost), but hope it was a once off and has been sorted now.

ps. Why not call Beta UK directly and discuss what size with them ? Ask about the lower revs thing.
 
The 20 will be perfectly adequate. If you have a 25 you will demand just the same horsepower, but of course at lower revs so prop will need to be different, but fuel consumption will be virtually the same, being a function of power used. You will be able to achieve effective maximum hull speed with either.

You might consider a feathering propeller rather than a folder - more expensive but generally superior on motoring and similar reduction in drag.
 
I have a Beta 20 HP fitted to my 1971 Offshore 8m (26'). It is fine, and the extra HP (I think it had a 9 or 10 HP Petrol originally) is great for punching against a strong tide, such as coming through Portsmouth harbour entrance against a 4kt tide.
 
Have you considered using a Bruntons Autoprop? It is self pitching, so adjusts to the conditions. In calm weather the blades will be set coarse, giving a higher speed for low revs. In tougher conditions the pitch will be much finer - the equivalent of a car with an automatic gearbox changing down to low gear for climbing a steep hill.

The Autoprop is particularly useful for motor sailing. Running the engine a little above tickover, with the prop blades set very coarse, should increase boat speed considerably in light wind. With a conventional prop the engine revs would need to be higher.

Incidentally Beta recently stated to me that there is absolutely no problem running a modern engine at low revs for long periods. We have just bought an engine from Beta with low revs use in mind, but wanting substantial extra power for rough water and strong tidal currents.
 
The 1GM10 on my boat drives her at 6 knots flat out, a little over hiul speed. She's done this through the water against the tide off Barfleur. The Saddler has a similar hull profile, so I would expect the 20 to be more than enough. When I re-engined both the engineer quoting for fitting and the supplier reccommended the Yanmar twin, but I considered it unnecessary then and do so now. Driving into a sea over powering the hull might get you in a little earlier but it will be at a cost in comfort as well as deisel.
 
Coaster said:
Have you considered using a Bruntons Autoprop? It is self pitching, so adjusts to the conditions. In calm weather the blades will be set coarse, giving a higher speed for low revs. In tougher conditions the pitch will be much finer - the equivalent of a car with an automatic gearbox changing down to low gear for climbing a steep hill.

The Autoprop is particularly useful for motor sailing. Running the engine a little above tickover, with the prop blades set very coarse, should increase boat speed considerably in light wind. With a conventional prop the engine revs would need to be higher.

Incidentally Beta recently stated to me that there is absolutely no problem running a modern engine at low revs for long periods. We have just bought an engine from Beta with low revs use in mind, but wanting substantial extra power for rough water and strong tidal currents.
Click to expand...

While the Bruntons Autoprop is pretty expensive it is IMHO the best you can fit. It's up to you to determine if you can afford it but it automatically adjusts for pitch under all conditions, even when motor sailing and ensures that whatever power you have is efficiently used. My feeling about engines is.... compare weight, price, and dimensions. If there is little or no weight penalty in having the bigger one and it's not very much more expensive I would go for it. You don't NEED it but if the additional power comes without penalty it's nice to have. You won't notice the difference in fuel consumption and it may even be better.
 
seascape1 - our S29's VP2002 is still going well so far, but the time will arrive for an engine change, so I'll be cheeky and ask what, in broad terms, is it all going to cost?
 
We have a B/K Sadler 29 with the original Bukh DV20, and have recently fitted a rev counter. 1900 rpm gives a little over 5kts in resonably flat sea, dropping to 4.5 kts pushing into waves and a head wind. At 2500 rpm (the most we can get, with the exisiting fixed 3 blade prop), speed goes up to a good 6.5 kts in flat water. If I was getting a new engine, I would probably go for around 20hp again, as it seems to get the boat up to crusing speed at around 2/3 revs. If you go for a larger engine, you could find that you don't work it hard enough, and diesels do like to be worked hard. Just my 2p worth....

Cheers

Andy
 
Just fitted a Beta 25 to a westerly konsort 29' twin keel.
Seems to be perfect for the boat. 5.8 Knots at 2,000 RPM at the moment while I am running it in.
Engine is very quiet even without sound deadening material at the moment. Very smooth and easy to fit. If you pay for the special engine feet it really makes the installation go smoothly
 
bit the bullet ordered the beta 25 with standard alternator but upgraded pulleys and belt also the waterproof instrument panel with the rev counter - anybody fitted one of these and if so where abouts are the most suitable sites in the sadler cockpit - suggetsions please ?
in response to cost question
around £4K for engine - dealt direct with beta -
sold old bukh but still have some new filters-water pump seals-pencil anodes -full engine manual etc if anyones interested PM me
as yet not fitted so all other bits will be additional - such as poss shaft-new prop after discussions will be a 3 blade 14x9-may be autoprop at some stage in future
regarding sound insulation to engine box -anysuggestions of suppliers/materials etc would also be appreciated
thanks once again for everyones comments
 
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