Hot Water

[LizG]

Apart from the fridge which is a big user of the battery, hardly anything else was used.  We were in the beer tent most the evening!

[Vaughan]

2 hours ago, Mowjo said:

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,,

It is true that some alternators need the warning light circuit to "excite" them, so it it doesn't work, check the warning light bulb before you check anything else. Most modern alternators are "self exciting" but you do need to rev up a bit to "cut them in".

Another side effect of these very low speed limits. Always rev up a bit after starting the engine and check the voltmeter is showing a charge, after that, you can drive around on tick-over for several hours, but the batteries will be charging.

[LondonRascal]

I am in the habit of when starting the engine to blip the throttle and get revs past that which the alternator will begin charging and the lamp indicating it is not extinguishes.

This really is a complicated subject and I don't want to get too deeply involved, but take BA she has two Alternators but their output is managed through a smart battery charging system so when the batteries are low the alternator will be putting out a great deal of amps, but when things are almost full their output might be limited to say 7 amps to 'trickle charge' the batteries until they are fully charged.

When I was last out on the boat, it was interesting to note our Solar panel which is wired to domestic bank was putting our a respectable 4.2Amps through its solar charge controller. This meant when moored and the fridge cut in, it was almost being covered by the Solar panels assistance from the sun. If you do not have a 204v shore powered battery charger on your home berth, the inclusion of a Solar Panel to keep your batteries topped up is very much worth while and no longer that expensive.

This one at 40w will at the best put out 2Amps which is very little, but over several days of good sunshine will ensure your batteries are full and things like a bilge pump running every now and then won;t be able to drag your batteries down.  It comes with all the wires, mountings and charge controller too for £76.00.  Link to buy

 

[Mowjo]

Thanks Vaughan! I couldn't remember what it was called, now I know it's the excitor, when I fitted my new 70amp alternator it did say in the destructions it dosn't cut in under 1800revs,,

 

[MBA Marine]

I was late to the party, but yeah alternator excitation thingy it's like Vaughan says.

one more little point, the light illuminates as it finds a ground through the alternator when the alternator spins up this ground becomes a live, put a live to both sides of a bulb and it goes out, but further to this if a relay is being used to charge two battery banks from one alternator the live to pull in the relay is often the excitation live, so getting to the final point a lack of excitation can lead not batteries that are not very excited at all in fact they could be a bill dull and flat.

Charging batteries can make some warm acid but what does all this really have to do with hot water? 

 

[Seriously]

Well back to hot water

 no improvement ,one last run back to boat yard today (3hr trip) can't see it changing but fingers x .

Did find what I think is a thermostatic valve . Or maybe a engine temp valve .only put my hand on it and the cable came out lol. So new crimp needed. It is Insulated taped on now

so may have sorted the temp of hot water , it being a lose wire  . The engine temp did not go above 4o again after a trip from s Walsham to Salhouse even when I removed cable from the said valve  it seemed to have no effect to engine temp gauge . So I assume this valve has nothing to do with engine temp. And is a gauge for hot water.

like Vaughan says time to call I  the pros , I not ready to change my engine just yet lol running a engine at 4o bust be as bad as running it at 140 

karlos 

mark I'll be giving you a shot shortly lol

 

 

 

[Vaughan]

Bizarrely, from the photo it appears your engine has been overheating in the past, and may have had a replacement cylinder head.

If the little valve is the one I think you mean, then that is a temp gauge or temp warning light sender.

If you are calling in Mark, I have no doubt it will be worth your while.

[MBA Marine]

Karlos you are welcome to give me call, but before you start spending money just have a little look at something, the heat exchanger (big thing with rad cap on top) at either end you have a round stepped rubber end cap with two hose clips, undo the two hose clips and slip off one cap, water will come out, what you should see is a cylindrical object protruding out and looking at it end on there should be a series of holes (tubes) down the middle. If you take the cap off and find just one big 3" hole then your'e missing a tube stack. your engine does look like its been ran hot and whipping the thermostat and tube stack out are a naughty way of getting a engine to run cool.  If the tube stack is there then reassemble and top up with coolant.

If its missing then you will need to start spending money. 

[Vaughan]

At the moment Mark and I can only judge on what you have told us, and a few photos.

It seems there is a "history" with this engine, and so Mark should have a look at the actual situation. I have a feeling that once he sorts out the basic engine temperature problem, then hot water for showers will follow from that.

Keep us posted!

[Vaughan]

2 hours ago, MBA Marine said:

If the tube stack is there then reassemble and top up with coolant.

Just a thought - the rubber "socks" at each end have 2 jubilee clips - the large one to grip the body of the heat exchanger and the small one to grip the protruding ends of the tube stack.

A mechanic has to ensure that the stack is placed in the middle of the exchanger body, so that the smaller clips can be done up first, and the whole assembly can then be fixed to the heat exchanger body, at both ends, by the large clips.

This is actually the way that the two circuits (raw water and fresh water) are kept separate. If these smaller clips have not been placed properly (and this is an easy mistake to make) then the engine will effectively be running on "direct" cooling, meaning that the thermostat becomes useless, the temperature will be too cool and there will be no effectve circulation to the calorifier tank. You are basically, pumping river water through the engine, and out the exhaust.

I know this sounds complicated but a small error in installation by a mechanic could cause the problems that Seriously is experiencing. I have seen this happen several times, when called out to a boat breakdown.

This does not, however, explain why the engine seems to have overheated in the past.

All the more reason why Seriously should have someone take a good look.

 

[Vaughan]

Just out of interest, how did Seriously get on with the heating problem? Is there any news?

[BroadScot]

11 minutes ago, Vaughan said:

Just out of interest, how did Seriously get on with the heating problem? Is there any news?

Hi Vaughan,

I haven't seen any further updates regarding that problem. Maybe we will read in the fullest of time.

Iain

[Seriously]

Hi folks 

sorry for the delay. As I always like to reply as any one reading this later may have the same issue . Would then might be able to resolve it

any one who knows me knows it's never that easy. So being s tight git decide I would try fixing it my self . So took robin advice ordered the bits from diperk and went down to boat with a friend Who happens to be a mechanic and works on Perkins engines for forklifts. 

So after a few  far good beers from fri  /sat  we took to stripping the engine down to get to the thermostat off . Once we got water pump off . We could not get backing plate off . We also could not see how the thermostatic valve could fit in it . So we googled again and defo said it was in water pump . The fan belt was too short which I had also purchased  oil switch was different so maybe diperk had also sent wrong thermostatic valve . So a lot of scratching heads . Well I will go and see if I can find one of the lads in boat yard for some much needed help . So I presented him with the water pump in my hand and asked him "is the thermostatic valve in here " nope  forget the guys name . I'm not sure wher it is so he followed us back to the boat .after a quick look we still did not no where it was. So all four of us are now googling .we then found pictures of on in postion .not in water pump. So we refitted water pump and the guy got us some gasket sealer. Thank you. Problem now is we undid four nuts on the thermostatic cover which was ok . The two through bolts were solid. My friend the mechanic said they would probably sheer . He would then need to take off the heat exchange take it back to Sheffield repair and bring back . Only problem was two weeks holiday was in a week . Decision made was made ,to leave it until after hols. Boat yard mechanic suggested it does run at 45 degrees which maybe it does or does not . Online manual agrees with Vaughan should be running hotter .

I

So  we have returned from our hols today 

water did get slightly hotter but so did the weather . Temp gauge never went above 50 degrees .  So at some point we will whip out thermostatic valve and change it. So I still can not say what the issue is . But hopefully  before the end of August thermostatic valve will be changed . If still not fixed Then it's time to hand over to MBA Marine 

[Vaughan]

There are various versions of the MC42 and this one was marinised by Duffields, who are no longer in business (unfortunately).

I have found two pictures of the MC42 water pump, both of which have a thermostat housing, behind a back plate, which is removable by 3 cross head set-screws, once you have removed the pump body from the engine. Unfortunately Susie and I have been unable to link these to you from the internet site. Presumably because we are not allowed to. . . .

I simply Googled Perkins MC42 and then there are pictures of parts, one of which shows the various water pumps.

I have also looked up the thermostat rating for this engine, which is 82 degrees C.

It occurs to me, when you say "water pump" do you mean the internal "circulating" pump, as would be found on a car, or do you mean the raw water pump? "Raw" means sea water cooling (or river water) and it is this which cools the "fresh" water in the heat exchanger. Your engine has these two pumps, but only the "circ" pump will contain the thermostat.

I have never had to change the thermostat in an MC42 as they are very reliable, which is why I had to think about where it was! So does your problem come from somewhere else? It seems your engine has been overheated in the past, so why? A blocked weed filter, which stripped the blades off the raw water pump impellor? And are bits of those blades still hanging around in the tube stack? As MBA has said, someone may have just taken a short cut to this problem, and "binned" the thermostat?

I suggest the time has come, if you want trouble-free cruising, to consult a professional marine mechanic. There is one who has already made excellent contributions to this thread, who would seem the obvious choice?

[BroadScot]

PM sent Vaughan ....

[Seriously]

Hi 

yes we  defo removed the circulating pump as all the online manuals showed it in the circu pump . once  the pump  was off it had a back plate as you have explained above ,which was solid  .We could not remove the cover with our current tools . So we had a mo and scratched our heads ,because all of us agreed , It did not seemed to be room in the housing to fit thermostatic valve .Unless the valve from diperk was incorrect . Once the mechanic from boat yard came over and agreed with us that it was not in water pump . I then went on google and found another manual it had a third location to where the thermostatic valve was  doh . I've spent last hour trying to find it again but have failed.

so I do agree with you it's almost time to call him in . I would from my own satasfication like to check the housing on the back of the heat exchanger . That the thermostatic valve has indeed been removed or is damaged. Is I will keep you posted and get some pictures of what I think is a thermostatic valve housing.

 

[MBA Marine]

On 7/28/2016 at 5:30 PM, Seriously said:

Hi folks 

sorry for the delay. As I always like to reply as any one reading this later may have the same issue . Would then might be able to resolve it

any one who knows me knows it's never that easy. So being s tight git decide I would try fixing it my self . So took robin advice ordered the bits from diperk and went down to boat with a friend Who happens to be a mechanic and works on Perkins engines for forklifts. 

So after a few  far good beers from fri  /sat  we took to stripping the engine down to get to the thermostat off . Once we got water pump off . We could not get backing plate off . We also could not see how the thermostatic valve could fit in it . So we googled again and defo said it was in water pump . The fan belt was too short which I had also purchased  oil switch was different so maybe diperk had also sent wrong thermostatic valve . So a lot of scratching heads . Well I will go and see if I can find one of the lads in boat yard for some much needed help . So I presented him with the water pump in my hand and asked him "is the thermostatic valve in here " nope  forget the guys name . I'm not sure wher it is so he followed us back to the boat .after a quick look we still did not no where it was. So all four of us are now googling .we then found pictures of on in postion .not in water pump. So we refitted water pump and the guy got us some gasket sealer. Thank you. Problem now is we undid four nuts on the thermostatic cover which was ok . The two through bolts were solid. My friend the mechanic said they would probably sheer . He would then need to take off the heat exchange take it back to Sheffield repair and bring back . Only problem was two weeks holiday was in a week . Decision made was made ,to leave it until after hols. Boat yard mechanic suggested it does run at 45 degrees which maybe it does or does not . Online manual agrees with Vaughan should be running hotter .

I

So  we have returned from our hols today 

water did get slightly hotter but so did the weather . Temp gauge never went above 50 degrees .  So at some point we will whip out thermostatic valve and change it. So I still can not say what the issue is . But hopefully  before the end of August thermostatic valve will be changed . If still not fixed Then it's time to hand over to MBA Marine 

one does like a challenge,  I have had my share of perky Prima fun of late, one key factor when getting parts is to find out if its a genuine marine engine or a LDV van engine, very different beasts.

[tjg1677]

Hello all,

 

been reading this one with interest. Back to the hot domestic water issue, if the engine is running at 50 degrees then it is fair to assume that the DHW is heating up proportionately. Not arguing with the fact that it should be nearer 75-80 mark at all but the DHW is evidently heating up, albeit in limited quantity as the OP suggests because you can only get one shower out of it.

Assuming that the shower is not lasting 40 minutes and assuming that the problem has always been inherent duringtheir ownership of the boat, then I would reckon on an incorrectly installed calorifier.

The calorifier will only heat up to whatever level the heating coils are sat at. i.e if they are halfway up the unit then you will only get a half calorifier full of hot water, if they are 3/4 of the way up, you only get 1/4 of a tank full etc etc.

 

Someone quite correctly suggested that the feed lines from the engine may be reversed, this is quite feasible. I have also seen horizontal calorifiers that are handed and have to be installed the correct way up because the heating coils are in the lower part of the unit and therefore if installed upside down, you only get a fraction of the tank heated cos the coils are at the top.

 

hope this rambling makes sense and helps to at least eliminate a possible cause.

ttfn

trev

[Vaughan]

Thank you for that, and welcome to the forum!

I am sure you are right (I know you are) on all these points but if it were me I would want to get the engine running at the right temperature (for its own sake as well) and then see if that improves matters.

Do we have any more news on this? I know Seriously has been cruising this summer, as he said so.

How did it go? Is the problem solved?

[JanetAnne]

Just to add my two penneth worth, fitting a little in line 12v pump in the flow pipe to the calorifier makes a huge difference to both speed of heating the water and the actual temperature itself meaning proper engine temp water much faster. Run it off the ignition circuit.

Alternator speeds can be altered by changing the diameter of the alternator pulley so that they run a bit faster at lower engine speeds. 

[Jim]

A few of my boaty chums suggested we fit an inline pump when we were struggling with our original (useless) calorifier. I never did get to try it but I can't see it would make matters worse. In the end, we bit the bullet and had a complete new 40ltr system fitted plus immersion which is perfect.  Our engine runs at 80 degrees and half an hours cruising provides a full tank of hot water.    

[BroadScot]

1 hour ago, JanetAnne said:

Just to add my two penneth worth, fitting a little in line 12v pump in the flow pipe to the calorifier makes a huge difference to both speed of heating the water and the actual temperature itself meaning proper engine temp water much faster. Run it off the ignition circuit.

Alternator speeds can be altered by changing the diameter of the alternator pulley so that they run a bit faster at lower engine speeds. 

What a clever talking boat you are JA !

Iain

[Seriously]

Hi All

So not really any  further on   just a quick update.

As I have said before taking the back   off the thermostatic valve  cover ,  could cause a couple  the bolts to sheer. So I need to plan to do it when I can return the following weekend.

I am now getting the temp to a regular 50 degree`s probably due to the a increase in revs when traveling (within the speed limit) also the river water temp is warmer . also the   hot water seems better  

I have read on the Darkside forum  on some one else question . Jason who works at ludhambridge boat yard . He worked  on and developed these engines while they were under the Duffields umbrella . on said forum ,says these engines do run cooler and if  its running at 50 Degree`s  not to worry

So I will  still check the  thermostatic valve at end of the month. I will then get professional to give he engine  the once over . Male pride and being a tight git want to check  the thermostatic valve myself.

Also need to double check the impeller in the water pump . when we were looking for the thermostatic valve we found the impeller. it did  not seem to be able turn inside its own  casing . It looks to me like the impeller is used as more a slow down the pressure of the water. Than pump it around so that suggest . There must be a second pump somewhere else . As I cant see the water being pulled from the river any other way As I've said its all a learning curve .Will try to get a picture  of the impeller next time I'm down ..to explain it better.

So no real move on but hopeful by the end of the month  we might have a answer

[Vaughan]

Thanks for the update.

Without getting technical, the impellor in your river water pump is not an "impellor". The circulating water pump (with the thermostat) is an impellor in that  it impels the movement of the water by its own rotation, a bit like a fan.

The river water pump is a forced water pump which works on the cam principle and physically draws in water and then expels it. This is done by the rubber blades squashing against the cam as they rotate, and is also why you can't seem to move it by hand.

If the blades are not cracked then leave it, but take it out in the winter, when you winterise the engine.

It is very important to get a good seal on the faceplate, if you have taken this off, as if it draws air, it will not draw water! I don't think they do Duckhams water pump grease any more so I recommend Morris K99 water resistant grease, available from Peachments in Brundall. Smear this on the blades of the "impellor" with your fingers, and on both sides of the paper gasket.

I said earlier that I had a feeling these engines run cooler and Jason has confirmed it. All the same I would like to see it hotter than 50, or you will not be getting enough hot circulation to heat up the water in the tank!

[Seriously]

Hi Vaughan

Thanks for your input most helpful.

When we took the faceplate off.  who ever took the  plate off and fitted a new gasket had not clean the old gasket off . so it  had the new gasket and the remains of the old gasket on the plate . I have just ordered some K99 grease . so will be greasing it up the next time I'm down. Again thanks for your help.