Hydraulic drive

[Bazzer]

I have a bounty 37 (cherry willow) and I think the hydraulic drive is not performing up to standard.

When at full throttle I can only achieve just over 4.3 MPH. (shown on GPS)


Any suggestions???

Q1 What is the hydraulic fluid used TQF or similar?

Q2 At what level should the tank be filled, mine appears to be just below just below the gauze filter

Q3 Who stocks the filters - Would a clogged filter cause the problem?

Thanks for any help or suggestions

Bazzer

[Nick West]

Hi Bazzer,
I had a very small problem with my hydraulic drive about a month ago, (It had lost some fluid over the last 12 months) so I went to Moonfleet in Stalham who told me it was not that important to put a specific type of oil in as long as it was specially designed for Hydraulic's, they did suggest that it should be drained so that all the oil was the same but I didn't and it seems OK, I think the oil just got a little "old", and as yet I have not lost anymore? I put about 1ltr in and the suggestion was to have about 75% oil and 25% free space for expansion, someone else might say differant

Just one thought, how about the size of your prop? on my last boat (an ex hire boat) they had put a smaller prop on so it wouldn't go to fast on purpose. is this possible on yours!

[Bazzer]

Thanks for that,, I will probably top up the oil a little,

As for the prop I havn't a clue, only owned it for a few weeks and as yet havn't had the benefit of seeing underside, only the surveyor did that.

What worries me is that I wouldn't like to be going through Gt Yarmouth having got my times wrong and hit a 5mph tide !!!

Bazzer

[Pas Vite]

Thanks for that,, I will probably top up the oil a little,

As for the prop I havn't a clue, only owned it for a few weeks and as yet havn't had the benefit of seeing underside, only the surveyor did that.

What worries me is that I wouldn't like to be going through Gt Yarmouth having got my times wrong and hit a 5mph tide !!!

Bazzer

what hp is ur engine ?

the hydraulic drive reduces the power by about 15% or more, so I have been told,

I have a 39hp Nanni & my max is about 6 > 7 mph MAX, cruise at 5 > 6mph, & I know some of the ex-hire 35/37s near me are no faster than me

[Bazzer]

The engine is a bog standard 1.5 BMC diesel. Dont know th HP It starts very well so seems in quite good condition with good compression.

I expected it to achieve 6mph flat out (2200rpm) and be able to cruise at around 4mph at 1500 rpm.

At 1500 rpm I can only just achieve 3mph and at 2000rpm 4mph (measured on the GPS).

On monday I was the slowest on river on way to Oulton from Brundall, It was embarrasing

Bazzer

[Nick West]

Hi Bazzer,
I have exactly the same engine BMC 1.5 and I can get 3.5MPH on 1500 revs and nearly 6 at 2000 I tend to not go over 2000 revs for any extended periods as the temperature tends to go up above 85 degrees but at 2000 revs she will run all day at 6MPH.

[boaters]

Hi Bazza,we have a 3 cylinder Perkins with hydraulic drive and at 3000 revs we get about 7 mph.Must admit it hums and is louder than we expected when we bought the boat ,how about you guys ? A friend with a 28 Bounty describes his problem as akin to slipping clutch? He is investigating and I will let you know when I hear his results.

[bitingmidge]

I've now had my boat running for enough hours to make a comment, and when I see all these MPH figures I just get green with envy!

I too have the "slipping clutch" experience. More revs just means more temperature and no more speed.

On the French canals there is a 6kph speed limit, which is our comfortable cruising speed, but we've just been from Nancy>Toul>Metz>Nancy on the Moselle, and with careful monitoring of the temperature gauge, managed to maintain some averages near 8kph - that's close to 5 mph or less than half the theoretical hull speed!

I'm sure the dear old Perkins is better than that, although I'm not sure about economy either, which seems to be around 2litres per hour.

Can anyone add any thoughts? My first reaction was that there is slip in the drive, but after thinking it through, I'm more inclined to think it's under-propped.

Cheers,

P

[bitingmidge]

It's pretty clear that I'm entirely in the dark as to the functioning of all of this!

I had a "discussion" with a technician today, he speaking French, me English, and the gist of the conversation was :

1) Your old Perkins is OK, it's just a bit smokey when it's cold, they are all like that.
2) Yes it leaks oil. Some engines are clean, yours isn't.
3) Don't bother with more than 2000 rpm, the hydraulics will not keep up at that point.

From all of that I gleaned that it is indeed hydraulic slip that's occurring, and I'll just get used to it.

Out of curiosity, where can I get bits? And is there such a thing as a reconditioned unit?

Cheers,

Peter

[Bazzer]

I have been speaking to people and in the UK at Norfolk he reccommended

Eastern Fluid Power Ltd., Gapton Hall Road, Gapton Hall Industrial Estate, Great Yarmouth, Norfolk NR31 0NL.
Tel: 01493 441353. Fax: 01493 440757. E-mail: sales@efphyd.co.uk

I am off there this afternoon to buy a new pressure guage to start diagnosis as to whether pump or motor is not performing.

When I get home I should have a digital strobe tacho tester that will be able to tell me the shaft speed accuratly and the compare with engine revs, I think it should be a 2-1 reduction.

Will let you know how I get on.

Bazzer