New owners preparing to take a JP3M to sea - help!

[steamraiser2]

Oh dear. Still as you can see from the pics " By Eck" purloined from our website we have had a few cracked JPs in our time. We may be able to help you with that. Some clear pics of the crack would be of interest and would certainly point the way towards deciding whether to repair or replace. Got a pile of JP3s and JP3Ms here so may be placed to assist you.

[George94]

That is very bad luck, but the experience gained won't be wasted.

 

If you can find the cash for a refurbed engine, you could perhaps get it installed quite quickly, and still proceed under your own steam. Steamraiser is the biggest Lister restorer (as far as I am aware), and has an excellent reputation, so you wouldn't have far to look or long to wait.

[flatplane8]

Hi Giant and Wren - any update for the new year? Hope things are going well.

[wren]

At the moment, I am learning to accept what cannot be changed: the weather in the North Sea...

[George94]

At the moment, I am learning to accept what cannot be changed: the weather in the North Sea...

 

Indeed. This is not the time I would choose to motor slowly down the East Coast. May would be more like it, although that can be chilly.

[ditchcrawler]

All the major coating manufacturers make 2 pack epoxy products (such as International's Interline 984) that are designed for the internal coating of white oil storage tanks and which with neither affect, nor be affected by, the fuel in the tank. One of these would be greatly superior to some of the "magic mixtures" sold for amateur use.

 

The challenge would be to obtain the stuff in small quantities - and to prepare the surface properly.

 

Chris G

When I worked offshore ours were blasted internally and coated by airless spray with two part epoxy

[Giant]

Well, time at last for an update.

 

[Photo by Charlie Hill - http://www.shipspotting.com/gallery/photo.php?lid=2013710]

 

After various other plans came and went over the winter, we eventually got offered a deal on a tow, by a tug that was coming back from the Humber to London and would otherwise be going empty.

 

It was supposed to be a tow all the way from Goole, but we found out at short notice that the port authority weren't going to allow the tow within the port limits. So we were faced with taking her out to sea on her own steam, escorted by the tug, and picking up the tow once we cleared the port.

 

We'd determined over the winter that the crack, whilst obviously a concern, was old and wasn't actively causing any problems or getting worse. So we took the bet that she'd stand up to a few hours flat out on the river, and went for it.

 

She didn't let us down - despite pushing her as fast as she'd go to get down the river before the tide turned against us.

 

Once clear of Hull we hooked up to the tug for a long and bumpy night & day at sea, keeping a constant watch on the bilges. We kept the engine ticking over the whole time at sea, just in case.

Early evening of the next day we were let go to make our own way up the Blackwater, and anchored there for the night before embarking on the final leg up to Maldon on the next tide in the morning.

 

In total about 40 hours on the engine between the main trip, last leg, and a final run once on the mooring to flush the cooling system with fresh water.

 

 

We now have the opportunity while she's at Maldon, to do whatever we're going to do with the engine, so we're figuring that out now.

 

In addition to the aforementioned crack, there is a knocking which seems to be associated with - or at least in time with - the firing of the no. 2 cylinder. Here's a video for you to hear for yourself:

 

 

I'd like to work out what this is - pissing in the wind of course if we're pulling everything out and replacing the block anyway, but I'm always curious to try and work things out.

 

Quoth the manual:

 

 

I think I can eliminate (a) and ©, since we checked the clearances quite carefully when refitting the heads, and the valves were fully cleaned up. I've rechecked the valve rocker tappet clearances since too. If (e) was occuring then I'd expect the flywheel to have come off the shaft by now as we pitched at sea! So my guess would be knackered bearings, except that there's another symptom: the no.2 head seems to be noticeably cooler than the other two. Perhaps this is just an artefact of the geometry of the cooling system, since the cold feed from below the silencer comes in just underneath no.2?

 

I've also had it suggested to me though that we might be dealing with some slop of the piston in the liner, which could explain both the sound and the cool head, as presumably any play of the piston would lead to some loss of compression.

 

What do you think?

[flatplane8]

First of all, congratulations on getting to your home mooring and a great looking barge. We especially like the wheelhouse and how it looks 'right'. Listening to you video, it sounds like our engine. Basically functioning well, but possibly a litte worn. If you are bored enough, listen to some other ones on YouTube, particularly Mike Askins JP2 in narrowboat Victoria. They all have that knocking sound at tickover. The only ones that don't are the freshly rebuilt ones by Marine Power Services, presumably due to fresh bearings all round. Our cylinders also run at slightly different temps, probably for the reasons you describe.

[magnetman]

Lovely boat

[steamraiser2]

Worn bearings I'm afraid. Easy enough to put right when you cure the cracked block issue as the crank will have to come out anyway.