Hot Water

[Seriously]

Hi all 

usually run the  engine for a minimum of two hrs a day but only at most 16-18 RPM 

russet has two showers and sleeps 8 people . Currently only able to get one shower before going cold. So my questions are .

1. Am I not getting the tank warmer enough ? ( as I run engine so low it does not heat water probably )

2. Does the tank fill with cold water as you start taking the hot water ?

3.cant really shower on the move due to having small children . One adult driving the other supervising 

4. Maybe a new tank picture enclosed looks like the original  ? Looks big enough tho to supply two showers

5. Engine belt has been screeching recently, think this would effect the alternator not hot water.

6. I assume the water is pumped around the engine to heat it ? So could pump be on way out ? 

7 going to run engine again  tomorrow and feel tank to get an idea how hot the tank does get.

all help gratefully received 

[Vaughan]

I will start by answering your questions with questions :

What is the make of the engine?

Are you running it in neutral, or in ahead gear?

What temp does the engine show, when running?

[Seriously]

Hi Vaughan 

always on the move running engines at moorings is naughty 

no temp gauge on upper helm always sail from upper hem come sunshine and rain ,mostly rain  so not sure I think last time I looked it was not much above 50 c but will have to check tomorrow after running it. Sorry 

Perkins MC42 

KF30266U

Thanks 

[ranworthbreeze]

Hi Seriously,

I could be talking utter rubbish, but if the belts are screeching maybe there s an issue with the pump, seized or impeller damaged that is putting a load on belts, if this is the case however I would have thought that the temperature would be a lot higher. 

Regards

Alan

[Vaughan]

Well for a start, the MC42 is a very nice little engine. they were designed as much more of a "marine" engine, in other words you can work on them from the top, rather than underneath. If you are only doing 1800 revs that is normal as these are a low revving, "long reach" engine.

When Crown Blue Line were building a lot of boats, we wanted to standardise on this engine, but Perkins could not guarantee that they would continue to produce them for more than 5 years, so we went for the Nanni instead. In our opinion the MC 42 was an excellent small inland waterways engine.

If you don't have a temperature gauge upstairs, then fit one! Any 4 cyl diesel should be running at 80 degrees minimum and some prefer 90. If you are only running at 50 this is bad for the engine. Did you know that pistons, when cold, are not circular? They only become perfectly circular, and thus fit the cylinders, when running at optimum designed temperature.

I suggest you have a boatyard look at the engine and check the thermostat. It sounds to me as if you have recently bought this boat, so maybe a good idea to have someone take a good look. You must certainly check the tension on the alternator belt, if not you will strip the belt. If it has been screeching a lot, you probably need a new one.

You may also have an air lock in the pipes which lead from the engine to the calorifier tank. Run the engine until warm and feel these pipes. If they are not hot to the touch, then you will not be getting hot water for your shower! In this case, with the engine running, ease off the jubilee clip on the upper of these two pipes, at the engine end, and see if you can bleed the air out. Be careful not to go anywhere near the alternator pulleys when the engine is running.

There are a few ideas for a start!

[Seriously]

Thanks guys 

screeching only happens for about thirty seconds so will look at that and I will get a temp gauge fitted  this season . I will check to make sure we have no air locks . I will let you know how I get on .

thanks again 

[MBA Marine]

Shes a fairly old looking tank, after going through Vaughan's points with bleeding the coolant pipes, next up, is that old relief valve drip drip dripping away? if so the hot water made is escaping and being replaced with cold. Not that, then is your tank half full with scale, Norfolk has some shockingly hard water and scale builds up to very large levels leaving you no room for water and covering the coil inside limits the heat exchange  possible, last point is the coil inside is sometimes not so clever and its construction means that even though the tank is from your pictures mounted the correct way up if the coil does not loop to the bottom of the tank it will only heat from the coil up over and a lot of the tank could still be cold.

[Vaughan]

Thanks Mark, I forgot about the pressure relief valve! At least there is one fitted. So many boats don't even have one.

I am trying to think back, but I seem to remember that the MC42 runs cooler than some others. Maybe 75 degrees? Even so, 50 would surely be too cool, and would not provide the same efficiency of heat exchange to the calorifier.

The MC 42 incidentally, was developed in close collaboration with Duffields in Norwich, who were Perkins main dealers and wanted an engine specifically adapted for the Norfolk Broads, and other inland waterways.

[Seriously]

wI'll check the drip drip tomorrow but assume it's not as I should have seen it when I was looking at tank earlier . 

Technolgies are great just snap chat my  alternator belt to my friend (car  mechanic) my belt is to slack so at least one issue solved 

Karlos 

 

[quo vadis]

Technolgies are great just snap chat my  alternator belt to my friend (car  mechanic) my belt is to slack so at least one issue solved 

 

amazing 

[Seriously]

19 minutes ago, Vaughan said:

Thanks Mark, I forgot about the pressure relief valve! At least there is one fitted. So many boats don't even have one.

I am trying to think back, but I seem to remember that the MC42 runs cooler than some others. Maybe 75 degrees? Even so, 50 would surely be too cool, and would not provide the same efficiency of heat exchange to the calorifier.

The MC 42 incidentally, was developed in close collaboration with Duffields in Norwich, who were Perkins main dealers and wanted an engine specifically adapted for the Norfolk Broads, and other inland waterways.

I have a shocking memory so take 50 with a pinch of salt 

[Vaughan]

3 hours ago, Seriously said:

Hi Vaughan 

always on the move running engines at moorings is naughty 

Just a general point that I would like to share, as there was a reason for my question.

Normally it is not good to run a diesel for long periods in neutral. The Nanni or Beta (which are the same engine) have a pressurised cooling system which will not come up to designed temperature unless the engine is doing some work. Leaving aside the green issues for a moment, if you want to run one of these, just to charge the batteries, then make sure your moorings are secure and run it on the quay in ahead gear at around 1500 RPM, checking that the temperature comes up to normal. This of course, will also provide you with good hot water.

If you run the engine at idle for long periods then you risk glazing the cylinder bores and thus having future problems with cold starting, due to lack of compression. Even more important since these are "indirect injection" engines. The only engine I have met where it is safe to run it in neutral without damage is the Perkins 4108, but never the BMC 1.5.

This is why I am attacking Seriously's problem from the engine end first, as the calorifier tank is a heat exchanger and you will not get an exchange if the engine is not hot enough in the first place.

[ExUserGone]

Check plumbing! Mine was fairly cool and short of water, turned out a previous owner had piped the cold water to the top of the calorifier and the hot to the bottom of the calorifier, quick pipe switch and lashings of hot water on tap.

[MBA Marine]

A dripping relief valve is not always obvious as it can be piped into the bilge or overboard, a tale tail is the water pump kicking in for a short burst at fairly regular intervals but no signs of plumbing leaking.

[Mowjo]

It might be worth checking that it has a thermostat fitted! running at 50 degrees sounds like it hasn't, I think most engines with one run around 70 degrees, I had that problem one one of my boats where the water was barely warm, when I checked there was no thermostat, I fitted a new one and had piping hot water, as others said it could be an airlock but my first port of call would be check the thermostat

[LondonRascal]

For information on your engine, and importantly if you need a replacement thermostat have a look at  Diperk: http://www.diperk.co.uk

If you can tell them the engine number they should be able to tell you what rating the thermostat needs to be. The engine number should be letters KF followed by ten digits.

Diperk's telephone number is: 0800 073 0424.

The water tank certainly does look, how to say 'well used' and that insulation will not be doing as much as modern equivalents. It might be an idea to consider saving for an upgraded one, perhaps with a built in electric element for when you're connected to shore power and want to get hot water.  Here are some tanks and prices: 

• ASAP Supplies
• Penguin Engineering
• Copper Cylinder

Should you ever need to overhaul the engine here is a complete kit for so doing: Perkins Perama-MC42 Overhaul Kit

[Seriously]

Hi all

thanks for your responses 

I have tighten the alternator belt and not too much, as instructed by my friend ,via snap chat  no more screeching on starting the engine.

We have had a cruise from Sutton - south Walsham  , the temp gauge never went above 40 degree so a dodge gauge or a engine problem. So will get this booked in.

the water tank is hot , but once getting my hands underneath the tank it is cold so as suggested , possible new tank required. Certainly like  the sound of electric element for when we are on hook up.

like most new things I lack confidence and understanding ,so as time goes by and  fingers x my knowledge will improve and hopeful ,pass on as you lot do 

will keep you all updated at least any one who reads this in future it may help them . 

Thanks again 

 

 

 

[MBA Marine]

4 hours ago, Seriously said:

Hi all

thanks for your responses 

I have tighten the alternator belt and not too much, as instructed by my friend ,via snap chat  no more screeching on starting the engine.

We have had a cruise from Sutton - south Walsham  , the temp gauge never went above 40 degree so a dodge gauge or a engine problem. So will get this booked in.

the water tank is hot , but once getting my hands underneath the tank it is cold so as suggested , possible new tank required. Certainly like  the sound of electric element for when we are on hook up.

like most new things I lack confidence and understanding ,so as time goes by and  fingers x my knowledge will improve and hopeful ,pass on as you lot do 

will keep you all updated at least any one who reads this in future it may help them . 

Thanks again 

 

 

 

No advertising here but make sure you shop around a bit with who you use, labour costs vary a lot. Not sure if Toby Cox is still doing engine work sub contract for Sutton Staithe if so he gets my recomendation knows his stuff and is a nice guy but other services are available.

[Vaughan]

Let's not jump into spending a lot of money at this stage. I agree with what Rascal says, and I also noticed from the photos that the tank insulation is - minimal - to say the least. This doesn't mean that the the tank should not be able to make hot water though.

You had a run from Sutton to South Walsham, so about 2 hours at very slow speed with the engine only getting to 40 degrees, so of course the bottom half of the tank will still be cold, on the basic principle that hot water rises, by convection.

I am still concerned that your engine is only running at 40 degrees. The temp gauge is unlikely to be "dodgy" - they either work or they don't - so, as others have suggested, you need to check the thermostat. Does it even have a thermostat?

If you get the engine running at the right temperature this will not only be better for its own life, but will probably solve your shower problem as well.

Incidentally, if you fit a 220volt immersion heater you must ensure that your shore power installation is up to all standards and well earthed to shore. 220 volts and water do not mix, and I have had bad and expensive experience with immersion heaters in calorifier tanks.

 

[Regulo]

Initial screech from the belt is due to the extra load put on by the alternator while chucking loads of amps at the batteries. It's usually caused by a slack belt (as you've found) or a worn and glazed belt. If it's been happening for a while, it might be worth changing it as a precaution - or get a spare to keep aboard.

[MBA Marine]

47 minutes ago, Regulo said:

Initial screech from the belt is due to the extra load put on by the alternator while chucking loads of amps at the batteries. It's usually caused by a slack belt (as you've found) or a worn and glazed belt. If it's been happening for a while, it might be worth changing it as a precaution - or get a spare to keep aboard.

I say change it and get a spare for the boat. slight digression but a common trick is to keep the old as a spare, this gets my goat a little and when i service a engine I cut the old belt open so it can't be reused, next service i will use the boats spare belt and replace the spare with a new.  

[Vaughan]

I have been thinking about Seriously's trip from Sutton Staithe to South Walsham, as with all the very slow speed restrictions that are now imposed in this area, you don't really get the engine above tickover.

It could be that certain boats need to think about changing the thermostat for one of higher rating, to give the engine a chance to get warmer, or it won't be able to make hot water.

"Horses for courses" and all that.

[LizG]

Replying to Vaughan's point about slow speeds, we trundled down from Horning to Thurne on Saturday, and getting behind slow moving boats didn't use many revs and by evening the battery bank 2 was flat with hardly any apparent use.  We ran the engine in neutral next morning with high revs and the problem was solved.  Coming back we went faster, punching the tide and wind and hopefully this problem has been resolved. Came as a bit of shock to have a flat battery.  i appreciate not the same as hot water - we don't have that but the engine is a Nanni

[LondonRascal]

I don’t want to hijack this thread and get myself into hot water haha, but the battery symptoms in my opinion would have little to do with the engine RPM you were traveling at, but one of a few other things.

I’d look into the age of your batteries and consider the fact if over 4 years old may be showing their age and replacement could be due. 

A flat battery is not at all good for them anyway.  Do you have a digital battery monitor (something like this) – if not it is a wise move to get one so you can see how many Amps are going into the bank and how many you are using at a glance. 

You might have not run for long prior to departing Horning, and the relatively short run to Thurne and then an evening of more use would have done the batteries in and so it is more a case of being a 'one off' event, but if happens again then it's a tell tale of things not being as should be.

It can happen rather suddenly – as did with Broad Ambition, a few tell tale signs and then rapidly got worse with not being able to have the Inverter left on for long, or heater running without low voltage issues – new batteries and the problems have all been resolved.

[Mowjo]

Sorry to disagree Robin but RPM can and does affect charging if your not carefull, with most modern alternators they don't start charging until you go past the 1800/2000 rev mark, once you hit that they will happily charge at low revs when your moving, I had the problem on my present boat, I rarely go above 1200RPM even when starting, went out all day and my battery's were nearly flat even though they were new battery's, when I checked things the previous owner instead of replacing the red ignition warning light had just connected them together under the dash making the circuit, I had one in my spares box and when I fitted it noticed that it didn't go out until I reved the engine to just above 1800RPM then it went out, I got my tester out to make sure, stopped the engine and the battery's showed 12.4v, started it as normal and it still showed 12.4v, Reved it to just over 1800RPM red light went out and it was charging at 14.4, so unless your alternator hits that cut in mark your battery's won't charge, once you hit it they will even charge on tickover, advice on that is always give your engine a little rev up when you start it,

Another point that someone like Mark may or may not confirm is that the Red ignition light forms part of the charging circuit, if it's not working or the bulb has blown the battery's won't charge,,