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7 minutes ago, dpaws said:

The pictures say it all really, thanks Paul!

 

 

20170315_103523.jpg

20170315_103558.jpg

IMG_0026.JPG

 

Nice pics, thanks.

 

what happened to the Samofa gearbox? You seem to have some sort of modern PRM contraption grafted on! 

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Yes, it's the PRM500 - bulletproof and cone free! Works extremely well together, the engine's a beauty; she plays a very merry tune with the long pipe...

 

The gearbox is on eBay (not my listing) 

Edited by dpaws
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One of our favourite engines ?, we have four of them at the moment with one just about to have its first run following a bare block restoration. Interest in them is growing particularly as they clearly have a Gardner connection which is obvious when you take them apart. Very popular in Holland in the same way that 2LWs are in the UK. 

 

We are in the throes of manufacturing all the overhaul parts for the 1S-108 and 2S-108 variants, liners , main bearings and gaskets etc on top of the wear parts we already do. The plan is to be able to offer overhaul kits for them. We are just completing the pre-production water pump drive unit to enable us to fit Jabsco pumps to the converted industrial variants we marinise.

 

 

 

  • Greenie 1
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1 hour ago, dpaws said:

Yes, it's the PRM500 - bulletproof and cone free! Works extremely well together, the engine's a beauty; she plays a very merry tune with the long pipe...

 

The gearbox is on eBay (not my listing) 

Did you find the dipstick?

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12 hours ago, RLWP said:

Did you find the dipstick?

Haha so good to put a face to the name! Yes thanks, eventually, though I had to ask! It's right down at engine bearer level on the port side. Solved the starter solenoid issue with a couple of taps with the back of a spanner :)

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12 hours ago, steamraiser2 said:

We are in the throes of manufacturing all the overhaul parts for the 1S-108 and 2S-108 variants, liners , main bearings and gaskets etc on top of the wear parts we already do. The plan is to be able to offer overhaul kits for them. We are just completing the pre-production water pump drive unit to enable us to fit Jabsco pumps to the converted industrial variants we marinise.

In fact it was your website that put me onto the Samofa's very existence, so thanks for that! I'd be very interested to chat about water pumps, could have an issue with mine, we're checking.... Any idea of the displacement pump's capacity or performance graph? I need to check it's performance at a fixed rpm against a flow meter to see if one of the valves is playing up.

 

 

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36 minutes ago, RLWP said:

It was that blingy knob that hid it

It's true... now, I wonder if the engine would sound even more glorious if those blingy knobs were brass plated... ? ?

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14 hours ago, dpaws said:

In fact it was your website that put me onto the Samofa's very existence, so thanks for that! I'd be very interested to chat about water pumps, could have an issue with mine, we're checking.... Any idea of the displacement pump's capacity or performance graph? I need to check it's performance at a fixed rpm against a flow meter to see if one of the valves is playing up.

 

 

No, I've never taken much notice of them, unless they are leaking of course. I'll have a look at our tech data  when I get a minute or go and measure the one on an engine in our warehouse. As I said in an earlier post we are going to fit all the ones we marinise with Jabsco pumps. Look better than the head mounted centrifugal pumps and less prone to leakage than the marine displacement type.

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3 hours ago, steamraiser2 said:

No, I've never taken much notice of them, unless they are leaking of course. I'll have a look at our tech data  when I get a minute or go and measure the one on an engine in our warehouse. 

That's very much appreciated - thanks - I'm curious too as to your water temperature whilst under load and, if you have an over temp alarm, what temperature it's set to trigger at.

 

This is the single port-side skin cooling tank which cools both the engine and the PRM500 but unfortunately it's proving to be insufficient... we're investigating...

 

Thanks again

P1090415.JPG

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Drifting briefly off thread...

 

"Il maestro" - in the yard today; a pleasure to witness his craft.

 

maestro.jpg

 

 

Edited by dpaws
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9 hours ago, dpaws said:

Drifting briefly off thread...

 

"Il maestro" - in the yard today; a pleasure to witness his craft.

 

maestro.jpg

 

 

 

Nice photo!

 

I didn't realise he was still in black and white. though.

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5 hours ago, Mike the Boilerman said:

I didn't realise he was still in black and white. though.

Thanks Mike - yes, he's still very happily "old school"; the monochrome seemed appropriate somehow ?

Edited by dpaws
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Finally got round to checking out the marine ram pump on one of our Samofa 2S-108s.  It runs at camshaft speed and, assuming a cruising engine speed of 1000 rpm, it can move about 5 gallons a minute not allowing for the inevitable losses in this type of pump. So not a large volume of water. Samofas as built seemed not to have had thermostats and run quite happily with the simple fan and large radiator they usually have in industrial use. Raw water cooled marine engines seem to be ok too. 

 

Narrowboat installations require a different approach however. It is pretty usual to run with a calorifier these days and this normally involves fitting a thermostat. Samofas run happily at up to 72c and this is the temperature of the stats we fit. We do find that the stat needs a 4mm weep hole and that eliminates the system having too much back pressure before the thermostat opens. Any appreciable back pressure will cause the pump to leak to some degree or other. That irritating habit aside the system will work without complaint.

 

The 2S-108 can produce a nominal 20 to 30 hp depending on engine top speed of 1000 or 1500 rpm. We would specify a baffled skin tank of between 8.5 and 10 sq ft in this instance.

 

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Wow - that's really very kind of you, thanks!

 

My installation does indeed include the calorifier circuit, the thermostat is set at 60°C; our external thermo-probes suggest that it's opening a little before that but that could be down to a lossy contact between the two. Our water jacket alarm triggers at 88°C if I recall... Our skin tank sounds to be the right size, though how it's baffled internally I don't know - Dave Harris was the fabricator, I'm confident that he'll have built it without shortcuts. In the past what's happened is that the water flows around the cooling circuit but fails to cool the cylinder head, causing the alarm to trigger at 88°C despite being able to hand hold the water pump inlet pipe. This combination of factors led to suspicions about the water pump.

 

Our investigation so far suggest that both the head gasket is secure (confirmed with block test fluid) and the water pump is working, however, the water in circulation seems to prefer to use the calorifier circuit rather than the skin tank even when after the thermostat has opened.

 

The flow through the calorifier can be controlled by an inline gate valve, and it's balancing this flow controlled by using the sight gauge on the water expansion (day) tank as a pressure gauge that appears to be the secret to having a happy engine. 

 

One part of the installation that nobody likes is the skin tank return (22mm) and the calorifier return (15mm) entering from opposing sides of a t junction in the flow return pipework; I'd prefer the 15mm to be fed into the main 22mm stream at an angle as shown.

 

Snip20180628_8.png.1146e3110037dc89ccba3ab025ed70a2.png

 

So, while this is being modified I intent to install a pair of these 25mm bore inline flow meters on the main 22mm cooling circuit so I can see exactly what's going on - their indication range is up to 30 l/min (7.9 gal/min).

 

Snip20180628_12.png.6da5a53b62c27783114d92bbb1b63fe2.png

 

- yes, overkill maybe but if the system's gone wrong once through trapped air or flow issues it could happen again and I was always taught that you can never have enough instruments!! After re-flooding the system we'll see if the flows balance any better so the alarm trips stop happening. 

 

 

 

 

Edited by dpaws
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Your calorifier supply line should always be of smaller bore than the piping to the skin tank by a significant margin. We sometimes fit a reducer in the line to act as an orifice plate to achieve this . Usually easier when we are plumbing up the engine to select the piping to provide for this. However, you have a reciprocating pump of poor design. By throttling the piping to ensure adequate flow to the skin tank you will increase the back pressure and the risk of a pump leak. Catch 22. It is one of the reasons we have developed the Jabsco conversion for these engines. Greater output,no back pressue issue, maximised circulation ,and most of all, no leaks.

 

As you say the skin tank return is 'orrid. Connect the calorifier via a flow tee upstream of the skin tank so that turbulence is minimised and then you can have a single pipe feed into the tank.

 

You can determine if your skin tank is properly baffled with the aid of an infra red digital thermometer. With the circuit fully warmed up the thermometer should be able to detect the flow of the coolant through the tank as it travels up and down as directed by the baffles. A well built skin tank should show hot at the inlet and a steady reduction until far cooler water exits the tank outlet.

A non baffled tank will probably stratify like warm and cold currents do in the sea. This will be visible using the infra red tool and is a sure sign of poor tank performance.

 

All this is relevant not just for the Samofa but for all displacement pumped motors, Lister JP , Gardner L2 etc. Set up properly you will never have an issue. Best find out before heading out on the Severn , Trent or Thames though.

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36 minutes ago, dpaws said:

Wow - that's really very kind of you, thanks!

 

My installation does indeed include the calorifier circuit, the thermostat is set at 60°C; our external thermo-probes suggest that it's opening a little before that but that could be down to a lossy contact between the two. Our water jacket alarm triggers at 88°C if I recall... Our skin tank sounds to be the right size, though how it's baffled internally I don't know - Dave Harris was the fabricator, I'm confident that he'll have built it without shortcuts. In the past what's happened is that the water flows around the cooling circuit but fails to cool the cylinder head, causing the alarm to trigger at 88°C despite being able to hand hold the water pump inlet pipe. This combination of factors led to suspicions about the water pump.

 

Our investigation so far suggest that both the head gasket is secure (confirmed with block test fluid) and the water pump is working, however, the water in circulation seems to prefer to use the calorifier circuit rather than the skin tank even when after the thermostat has opened.

 

The flow through the calorifier can be controlled by an inline gate valve, and it's balancing this flow controlled by using the sight gauge on the water expansion (day) tank as a pressure gauge that appears to be the secret to having a happy engine. 

 

One part of the installation that nobody likes is the skin tank return (22mm) and the calorifier return (15mm) entering from opposing sides of a t junction in the flow return pipework; I'd prefer the 15mm to be fed into the main 22mm stream at an angle as shown.

 

Snip20180628_8.png.1146e3110037dc89ccba3ab025ed70a2.png

 

So, while this is being modified I intent to install a pair of these 25mm bore inline flow meters on the main 22mm cooling circuit so I can see exactly what's going on - their indication range is up to 30 l/min (7.9 gal/min).

 

Snip20180628_12.png.6da5a53b62c27783114d92bbb1b63fe2.png

 

- yes, overkill maybe but if the system's gone wrong once through trapped air or flow issues it could happen again and I was always taught that you can never have enough instruments!! After re-flooding the system we'll see if the flows balance any better so the alarm trips stop happening. 

 

 

 

 

This is nice,were did you find these(flow indicators)?

/Christian

Edited by BM 1051
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3 hours ago, BM 1051 said:

This is nice,were did you find these(flow indicators)?

/Christian

Hi Christian, I googled :D http://flowpoints.co.uk/ the main page, here the type F http://flowpoints.co.uk/products/type-f/ 

 

and to find on a famous trading website try searching for "Flowpoint sight flow indicator 1" Bsp stainless steel 250 deg 16bar flap plate" (£120 each)

 

Snip20180628_13.png.281c637e5f3de6c18c7ae8248e368626.png

 

The 25mm bore is the one I've selected by matching the typical flow rate to approx. 70% of full scale indication. The step up from 22mm dia. domestic copper pipe to 25mm through the meter shouldn't have any significant consequences.

 

Edited by dpaws
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3 hours ago, steamraiser2 said:

Your calorifier supply line should always be of smaller bore than the piping to the skin tank by a significant margin. We sometimes fit a reducer in the line to act as an orifice plate to achieve this . Usually easier when we are plumbing up the engine to select the piping to provide for this. However, you have a reciprocating pump of poor design. By throttling the piping to ensure adequate flow to the skin tank you will increase the back pressure and the risk of a pump leak. Catch 22. It is one of the reasons we have developed the Jabsco conversion for these engines. Greater output,no back pressue issue, maximised circulation ,and most of all, no leaks.

 

As you say the skin tank return is 'orrid. Connect the calorifier via a flow tee upstream of the skin tank so that turbulence is minimised and then you can have a single pipe feed into the tank.

 

You can determine if your skin tank is properly baffled with the aid of an infra red digital thermometer. With the circuit fully warmed up the thermometer should be able to detect the flow of the coolant through the tank as it travels up and down as directed by the baffles. A well built skin tank should show hot at the inlet and a steady reduction until far cooler water exits the tank outlet.

A non baffled tank will probably stratify like warm and cold currents do in the sea. This will be visible using the infra red tool and is a sure sign of poor tank performance.

 

All this is relevant not just for the Samofa but for all displacement pumped motors, Lister JP , Gardner L2 etc. Set up properly you will never have an issue. Best find out before heading out on the Severn , Trent or Thames though.

You are very kind, thank you; you've described a scenario that makes complete sense, gagging in of the calorifier circuit which then consequently buggers up the pump's output.

 

Dare I ask the cost of your Jabsco pump, and also about space restrictions for fitting it as my flywheel's face is snug up against a bulkhead forward - do you have a photo on one in situ?

 

Now, if I understand you correctly you'd feed the calorifier return back before the skin tank - that would mean it taking longer before the thermostat opens... what would the real consequences for the engine be over time with this delayed warm up, or can the difference be considered to be insignificant? Unfortunately our skin tank's hidden behind panelling and linings etc so detective work's nigh on impossible, but I'll cross fingers for now...

 

Thanks again

 

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4 hours ago, dpaws said:

 

One part of the installation that nobody likes is the skin tank return (22mm) and the calorifier return (15mm) entering from opposing sides of a t junction in the flow return pipework; I'd prefer the 15mm to be fed into the main 22mm stream at an angle as shown.

 

Snip20180628_8.png.1146e3110037dc89ccba3ab025ed70a2.png

 

 

How about a proper injection tee? Instructions on how to make one at http://diy.torrens.org/HowTo/Injector/index.html. This is for 28mm/22mm but you could do similar with 22mm/15mm.

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It's interesting, but comes with it's own set of problems which the author concludes with "a bend just before the venturi would cause vortices which themselves are areas of reduced pressure. At a distance from the bend, flow would be more laminar." 3D printing one would be much better but it takes less time to press the buy now online that it does to open up the CAD program!

 

(Fortunately my old man's a fluid dynamics expert and in his opinion the simpler swept t is more than sufficient)

Edited by dpaws
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1 hour ago, dpaws said:

Hi Christian, I googled :D http://flowpoints.co.uk/ the main page, here the type F http://flowpoints.co.uk/products/type-f/ 

 

and to find on a famous trading website try searching for "Flowpoint sight flow indicator 1" Bsp stainless steel 250 deg 16bar flap plate" (£120 each)

 

Snip20180628_13.png.281c637e5f3de6c18c7ae8248e368626.png

 

The 25mm bore is the one I've selected by matching the typical flow rate to approx. 70% of full scale indication. The step up from 22mm dia. domestic copper pipe to 25mm through the meter shouldn't have any significant consequences.

 

Thank´s

I didn´t know what to look for, did not know the name.

One of those gunmetal would be nice on the Hundested engine.

/Christian

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