Arcrite narrowboat

[Pamber1106]

Hello just shot in the dark. I own 1985 arcrite fabrication 40 ft narrowboat. Would anyone know of how I could obtain copies of  construction drawings for this type of boat. Specifically the design of fuel tank. I know they made 100 and went over to building cruisers. Any pointers will be very much appreciated 

[David Mack]

You are assuming that there were any construction drawings in the first place!

[Tony Brooks]

8 minutes ago, Pamber1106 said:

Hello just shot in the dark. I own 1985 arcrite fabrication 40 ft narrowboat. Would anyone know of how I could obtain copies of  construction drawings for this type of boat. Specifically the design of fuel tank. I know they made 100 and went over to building cruisers. Any pointers will be very much appreciated 

Frankly I think you have little chance. Narrow boats are like Topsy, they just growed. I doubt a naval architect has been within 100 miles of any narrow boat builder, especially older boats. The builders tend to use the ways of fabrication  and designs from their heads, it seems to me to be a very empirical process that gets refined as each build is completed.

 

I have no knowledge of Arcrite but the typical design f the fuel tank on the majority of narrow boats is" find an off cut of steel that more or less fits across the stern of the boat inside and weld it into place so the off cut, uxter plate, hull, and stern deck all come together to form the tank. Far fewer boats have rectangular tanks using the baseplate, hull side and  new plates to form the tank.

 

Now, if you have a problem let us know and we may be able to be more helpful.

[Pamber1106]

Thanks for reply. Problem is water in fuel. Have had tank cleaned etc twice it was absolutely spot less. Fitted racor water filter. Ran fine for two weeks in marina stationary but under pressure water gets in. Fuel tank is two separate joined by connecting tube. General concensus is water going up through rudder tube and in too tank via possible weakness in steel tube. Head gasket good and checked all other connections. Any thoughts much appreciated 

 

[Jen-in-Wellies]

10 minutes ago, Pamber1106 said:

Thanks for reply. Problem is water in fuel. Have had tank cleaned etc twice it was absolutely spot less. Fitted racor water filter. Ran fine for two weeks in marina stationary but under pressure water gets in. Fuel tank is two separate joined by connecting tube. General concensus is water going up through rudder tube and in too tank via possible weakness in steel tube. Head gasket good and checked all other connections. Any thoughts much appreciated 

 

Does the rudder tube actually go through one of the tanks? If so, this is a weak point in a lot of boats. The steel wall of the tube is generally less thick than the uxter plate and side walls that make up the other sides of the tank that are in the water. In addition, it doesn't get blacked, as it is largely occupied by the tiller. A perfect place for corrosion around the water line.

[David Mack]

Rudder tube rusting through is not unknown in older boats. It never gets blacked, or even inspected, until the problem shows. If you are not leaving an oily film behind you, then diesel is not leaking out, which means the hole is located at the top of the tube, or perhaps it was never properly welded to the deck plate at the top. It's not that big a job to have it cut out and replaced. And no construction drawings are needed.

Other most likely cause of water in the fuel tank is rainwater leaking in/around the fuel filler, especially if this is of the type which is flush with the deck. Have you checked the condition of the o-ring under the filler cap?

[Tony Brooks]

12 minutes ago, Pamber1106 said:

Thanks for reply. Problem is water in fuel. Have had tank cleaned etc twice it was absolutely spot less. Fitted racor water filter. Ran fine for two weeks in marina stationary but under pressure water gets in. Fuel tank is two separate joined by connecting tube. General concensus is water going up through rudder tube and in too tank via possible weakness in steel tube. Head gasket good and checked all other connections. Any thoughts much appreciated 

 

 

Two separate tanks joined with a tube suggests one either side but the rudder tube is in the centre of the boat so I must be missing something. If the rudder tube goes up through the tank like most boats then I agree, either rudder tube or filler.

 

If the filler is a so called flush one they are well known for leaking rain water past the rubber seal for the cap. Fillers have also been known to leak where the fancy fuller body is bolted onto the deck. If the filler is just a threaded tube stuck out of teh deck with a female cap on it they are far less likely to leak (water can't run up hill) but where the tube is welded dot the deck just might be porus.

[Pamber1106]

Yea think you definitely got it right. Think next course is drain tank again and get camera in there thanks 

10 minutes ago, David Mack said:

Rudder tube rusting through is not unknown in older boats. It never gets blacked, or even inspected, until the problem shows. If you are not leaving an oily film behind you, then diesel is not leaking out, which means the hole is located at the top of the tube, or perhaps it was never properly welded to the deck plate at the top. It's not that big a job to have it cut out and replaced. And no construction drawings are needed.

Other most likely cause of water in the fuel tank is rainwater leaking in/around the fuel filler, especially if this is of the type which is flush with the deck. Have you checked the condition of the o-ring under the filler cap?

Neck filler is old school so is raised think must be tube going to get camera in have look. Thanks 

[Mike Jordan]

With care, a Schrader valve and  foot pump might enable a low pressure test?

[Tony Brooks]

46 minutes ago, Mike Jordan said:

With care, a Schrader valve and  foot pump might enable a low pressure test?

 

Good idea. A wrap of rubber under a jubilee clip on the filler and a big rubber cork with the valve assembly wedged into it should be enough to produce bubbling inside the tube if the tank is empty. Otherwise eventually a rainbow film on the water (not a good idea).

[Mike Jordan]

I was thinking along the lines of turning off the engine fuel pipe tap and pushing a little air down the vent pipe, that would test the filler cap as well. Sight unseen it’s difficult to suggest methods.

[philjw]

2 hours ago, Tony Brooks said:

 

Two separate tanks joined with a tube suggests one either side but the rudder tube is in the centre of the boat so I must be missing something. If the rudder tube goes up through the tank like most boats then I agree, either rudder tube or filler.

I had a cruiser stern boat built by Arcrite in 1983.  As I recall there was a removeable plate that exposed the rudder stock which was not in a tube. So there would have been two tanks with a balance tube between them.  Maybe the top section was common with a short rudder tube.  The design of the Arcrite boats was pretty much a straight copy of the Harborough hull.  I believe that the two guys who owned Arcrite had previously worked for Harborough Boats.

[Tony Brooks]

17 minutes ago, philjw said:

I had a cruiser stern boat built by Arcrite in 1983.  As I recall there was a removeable plate that exposed the rudder stock which was not in a tube. So there would have been two tanks with a balance tube between them.  Maybe the top section was common with a short rudder tube.  The design of the Arcrite boats was pretty much a straight copy of the Harborough hull.  I believe that the two guys who owned Arcrite had previously worked for Harborough Boats.

Thanks, but without a photo and without having seen one I can't envisage  it.

[David Mack]

1 hour ago, philjw said:

As I recall there was a removeable plate that exposed the rudder stock which was not in a tube

If there is no rudder tube what keeps the water out?

[philjw]

2 hours ago, David Mack said:

If there is no rudder tube what keeps the water out?

Two complete tanks side by side with a gap between them, Rudder stock between the two. Both tanks watertight.  A common to both top to the tanks with a tube just bigger than the rudder stock bolted (welded?) to the top plate through which the rudder stock passes.

[philjw]

https://www.alamy.com/stock-photo-people-on-a-canal-barge-on-a-rainy-day-travelling-along-the-shropshire-138059210.html?pv=1&stamp=2&imageid=7C85BA73-E745-42EC-B0AE-90ECBABD2F43&p=355664&n=0&orientation=0&pn=1&searchtype=0&IsFromSearch=1&srch=foo%3dbar%26st%3d0%26pn%3d1%26ps%3d100%26sortby%3d2%26resultview%3dsortbyPopular%26npgs%3d0%26qt%3dbarge%20rudder%26qt_raw%3dbarge%20rudder%26lic%3d3%26mr%3d0%26pr%3d0%26ot%3d0%26creative%3d%26ag%3d0%26hc%3d0%26pc%3d%26blackwhite%3d%26cutout%3d%26tbar%3d1%26et%3d0x000000000000000000000%26vp%3d0%26loc%3d0%26imgt%3d0%26dtfr%3d%26dtto%3d%26size%3d0xFF%26archive%3d1%26groupid%3d%26pseudoid%3d%26a%3d%26cdid%3d%26cdsrt%3d%26name%3d%26qn%3d%26apalib%3d%26apalic%3d%26lightbox%3d%26gname%3d%26gtype%3d%26xstx%3d0%26simid%3d%26saveQry%3d%26editorial%3d1%26nu%3d%26t%3d%26edoptin%3d%26customgeoip%3d%26cap%3d1%26cbstore%3d1%26vd%3d0%26lb%3d%26fi%3d2%26edrf%3d%26ispremium%3d1%26flip%3d0%26pl%3d

 

Imagine this one but with a plate covering the gap where the rudder stock passes through.

[ditchcrawler]

2 hours ago, David Mack said:

If there is no rudder tube what keeps the water out?

Black Prince style

[Tony Brooks]

2 hours ago, philjw said:

Two complete tanks side by side with a gap between them, Rudder stock between the two. Both tanks watertight.  A common to both top to the tanks with a tube just bigger than the rudder stock bolted (welded?) to the top plate through which the rudder stock passes.

 

That kind  of confirms my thoughts. If the tube leaked it would be outside the tanks and into the boat. Philjw talks about a removable steel plate. I wonder if the OP's boat has this setup and if so has he taken the plate off.

[magnetman]

Is the fuel tank "open all hours"? 

 

 

[Tracy D'arth]

Is the tank base the uxter plate?

[Pamber1106]

20 hours ago, David Mack said:

Rudder tube rusting through is not unknown in older boats. It never gets blacked, or even inspected, until the problem shows. If you are not leaving an oily film behind you, then diesel is not leaking out, which means the hole is located at the top of the tube, or perhaps it was never properly welded to the deck plate at the top. It's not that big a job to have it cut out and replaced. And no construction drawings are needed.

Other most likely cause of water in the fuel tank is rainwater leaking in/around the fuel filler, especially if this is of the type which is flush with the deck. Have you checked the condition of the o-ring under the filler cap?

Many thanks to all for help. Going to try pressure test. But think it's going to be rudder tube like said probably corroded. So presume out of water job. 

[Tony Brooks]

4 minutes ago, Pamber1106 said:

Many thanks to all for help. Going to try pressure test. But think it's going to be rudder tube like said probably corroded. So presume out of water job. 

 

Any chance of a photo of your twin tank setup plus info on the existence or not of the removable steel plate that has been mentioned. Twin tanks with a rudder tube in one makes no practical sense, so I still don't understand. I not that you have not answered Tracy's question about the uxter plate forming part of the tank. A photo will hopefully make it much clearer.

[Pamber1106]

Will try upload some photos. Have no removable plate on stern. Inside Hull have only flat still plate but when we cleaned tank cut second hole and could see pipe at bottom joining both sides together so we presume tiller runs up inside and water getting in through the tube and small pipe at bottom. To be honest had engineering friend look at it who works for local canal hire company and he came to same conclusion 

[Tony Brooks]

2 minutes ago, Pamber1106 said:

Will try upload some photos. Have no removable plate on stern. Inside Hull have only flat still plate but when we cleaned tank cut second hole and could see pipe at bottom joining both sides together so we presume tiller runs up inside and water getting in through the tube and small pipe at bottom. To be honest had engineering friend look at it who works for local canal hire company and he came to same conclusion 

 

Thanks, any chance of a simple diagram of what you saw.

[Pamber1106]

Can't upload other file. As to big. Basically on deck tiller is has plate with four bolts holding it on deck. When you crawl inside all that faces you is a flat piece of steel. But have solid stern with no plate. 

This may be better picture