Braunston auto propeller

[Crowblack]

Brunton disadvantage ?

None as far as I can see, my experience it's a fantastic piece of kit, both for sailing and berthing.

Don't understand Herman's comment about minimum speed being 3/4kts, we are able to creep into marina berths at very low speed, with the engine in gear, no rev's with the shaft just turning.

On the other hand if you have adverse conditions it's also possible to drive the boat into a berth - and because the prop has such good grip on the water a burst of astern easily brings her to a stop.

Agree with the comment about cleaning and servicing, we clean, polish and lanolin ours before launch and at mid season scrub and grease the bearings thoroughly once a year before launch.

 

[Bosun Higgs]

Not entirely Americans that have problems. On some boats the Brunton, however well-maintained, seems to produce a lot of shaft vibration. I had this problem on my Rustler 36, and was told by them wot know at Rustler that this seems to be a recurring problem with this particular marque. I've now replaced it (the prop, not the boat) with a Darglow Featherstream which behaves much better.

Chatting to Bruntons this morning they told me about a case of vibration that they had had with an autoprop on a boiat like mine - (24mm shaft, "soft" cutlass bearing, rope cutter, grp stern tube) - and which was only solved by removing the cutter so that the weight of the heavy Autoprop was nearer the bearing. They were impressively honest.

But then I already have bad vibration from a Radice folder.

 

[dulcibella]

The cause of the vibration problems experienced by some Rustler owners may be emerging from this thread. My Brunton (like its successor the Featherstream) was on a 1.25" shaft with a stripper rope cutter immediately in front of it. No p-bracket as this is a long-keeler with a keel-hung rudder, but inevitably the prop is close to the stern (within a cut-out in the rudder). Since the pitch adopted by the Brunton blades is the resultant of centrifugal force and the prop's speed through the water, the pattern of water flow around the prop is likely to be pretty complicated and may disturb the smooth setting of the pitch. Or am I talking cobblers?

 

[davidfox]

Never had any vibration nor any problem with being unable to go slow. That was on a Sun Legende 41 with a Yanmar 44hp with a 30mm dia shaft, 3 bladed Autoprop. This prop has done around 25,000mls.

I have an almost identical set up, have you had your prop serviced yet? mine was done by Bruntons, (it should be done every thousand hours) it cost £380!! having said that it looks brand new.

 

[Robin]

I have an almost identical set up, have you had your prop serviced yet? mine was done by Bruntons, (it should be done every thousand hours) it cost £380!! having said that it looks brand new.

I adjusted the blades myself when we bought the boat and even though I bought the spare bearings kit back then didn't change them until last winter (Jan 2009). I can't remember the original kit price but it was all done by our club engineer and cost very little in labour even including servicing the Ambassador cutter and fitting new bearings to that. The only reason we had the prop serviced was that there was an intermittent clicking noise heard which was caused by the blades on the cutter touching as one was bent slightly and the (8 year old) PTFE bearing shims were worn. Since I had the prop kit and it was now 13 years of running with just the one adjustment I thought it worth doing. The bearing balls were pretty much OK but the bearing carriers were pitted so it was indeed worth doing ready for another 13 years!