Larkboy

I would like to thank everyone for their input on this, much appreciated. although the shaft is scuffed it appears to have lost next to nothing in diameter so I think I will order a Centaflex coupling with its collet clamping system. Out of interest could I use an R & D bobbin to bolt onto the gearbox and then bolting the coupling to that which would allow me to cut 80mm from the end of the propshaft? I'm not sure of the loadings that might create on the gearbox output shaft. ASAP supplies sell R & D couplings to fit metric shafts.

I figured it didn't have a keyway or locking screw so that if the prop hit anything solid it would spin the shaft in the coupling to protect the gearbox?

There is next to nothing removed from the diameter, although I can't check it properly right now as my verniers are at work, it's just got surface scuffing. I think it's going to be Centaflex here we come...🙂 Thanks for your helpful input.

Thanks again for the reply. I am pretty gentle on the gearbox and always pause in neutral before changing direction and our engine tickover is about 750-800 rpm. I change the gearbox oil yearly and find hardly any residue on the sump plug magnet. From what you said about the Centaflex it uses a collet arrangement to clamp the shaft which would be far more efficient than the existing split clamp.

I've been looking at the Centaflex flexible couplings and it looks like I need the M127 for a 30mm shaft. Anyone with experience of these? I take it they're pretty straightforward to fit. Be good to hear from anyone that's put one on a 2005 ish Liverpool boat with Isuzu 35 and PRM 120 gearbox. Does it make the transmission much smoother?

Thanks for the reply. The locking stud is one I fitted a couple of years ago. I drilled and tapped the coupling and drilled a dimple in the shaft. Since taking the pic and posting the original post I've found that the end of the grub screw had sheared off and that is what can be seen in the photo. I've since got it out.

I agree completely with this and I'm a welder/fabricator of 40 years standing. There's welding and then there's welding!

We used chlorinated rubber paint on the inside of the hull of our 1966 Foreland 12' 6" tender which we are doing up and it's very good. we sanded the surface, used a primer and put a couple of good coats on. Would definitely use it again. Our paint was from paints4trade.com.

Got problems with the propshaft and coupling. We towed our friends 70' narrowboat to the drydock to be blacked after their skintank failed and the extra strain on the drivetrain has caused the shaft to slip in the coupling. the coupling is now quite worn but the shaft seems to have lost little in the way of diameter but is rather scuffed. I would quite like to fit a centaflex coupling, would it clamp up alright on the scuffed shaft? R & D marine do a bobbin which would allow me to cut the damaged portion of the shaft off, but would this together with said centaflex put too much strain on the gearbox (PRM 120) output bearing? The boat is a 56' Liverpool/New Boat Company model with an Isuzu 35, PRM120 gearbox and Vetus 30mm shaft and stern gear. Any advice would be much appreciated, thanks.

I bought our boat brand new 11 years ago and it came with an Arrow fires Becton Bunny 4kw stove. I have to say it's been brilliant and is still on its original grate! It's on its third door glass and I've replace the fire bricks once and folded up a stainless baffle at work when the original rotted through.

Greenie. David

We use a degreaser at work that you mix with 2 or 3 parts water and it works brilliantly. Unfortunately I'm away on holiday until next week so can't supply you with any details until Monday. If you're still interested then let me know and I'll give you the details....it really is very good.

You really do like to belittle anything contradictory to your own views don't you? Others can't possibly have a valid opinion, and for your information I don't go down the pub as I don't drink, I prefer to read.

Hmmmmmm, from a lot of what I've read on here and elsewhere, including the press over the last couple of years would indicate that in lots of cases they're not, far too often.

That's all fine then, maintain the status quo, everyone's happy and the C&RT and E.A maintain the waterways in an acceptable state and increase their license fees year on year....