Polly Graff

Now that is a thought. To be honest, I can't see how water could be getting into the exhaust system but you never know. While I was doing the work I obviously had to disconnect the exhaust and I had it tied up on the level with a piece of rope for six months. I don't think water could have got into it, as such, but I suppose six months worth of condensation could create quite a build up. I do get a lot of condensation in the engine compartment. When I go down there its often dripping of the underside of the stern deck, above me. Thanks for this thought - I'll try it and see what happens once I've tried a few of the other suggestions I've received. Thanks again.

Thanks again for all these replies and apologies for delay in responding. I ran out of 'boat time' and had to come home. A lot of questions/suggestions have been made so I'll work through them. Thanks Tracey D'Arth - I'll try running it with no cap and if I get bubbles I'll try taking the skin tank stud out again and see if gas or water comes out. It doesn't have a calorifier. If I start disconnecting the top pipes (thermostat housing, pipe that leads to the skin tank, heat exchanger, etc.,) won't that just result in any coolant that is being displaced to the top of the system (i.e., in the heat exchanger and the thermostat housing) pouring out? How will I know if there is gas in there as well? (Sorry these are probably simple questions but I'm new to this.) I didn't grease the head gasket. I thoroughly cleaned the top of the engine block before refitting everything - I couldn't see anything obviously wrong with it. Re the original gasket - I was getting blue smoke and after ruling out obvious things, I took the head off and got the engineer to come and have a look. He checked the bores and concluded they were fine - no evidence of oil burning off that way but he observed that the gasket had blown between the second and third bores and suspected that oil may be getting through to the exhaust system through that. Weirdly, I was not losing oil and never had to top it up. Irritatingly, when the white smoke eventually died down after I renewed the head gasket, I still had the blue smoke problem! Thanks DMR - the white smoke is pure white and, as I said, smells and feels like steam. I do get blue smoke once the white smoke stops. Not masses of blue smoke - just a bit more than I feel comfortable with. I'm not averse to taking the head off again once I've ruled out other possibilities. I got the gasket (and everything else) from Calcutt boats - which I believe are highly thought of - but I suppose a dodgy gasket is a possibility. Thanks Magnetman - yes, I'd read about the possibility of putting the gasket on the wrong way round so kept the old one, stored the right way up, to make sure I didn't make that error. I also looked at various sites on line and You Tube as belt and braces. Thanks Tony - I removed the injectors before sending the head in to be skimmed and stored them in order. I didn't touch them again until I refitted them. I replaced the little copper washers. I did look at the pintals and didn't see anything different to the pictures I had of them. Also, just thought I'd mention that, following on from a previous reply I had from you some months ago, I replaced the 10/40 oil with 20/50 oil for older engines. Thanks Ditchcrawler and Tony - cooling is via a skin tank. There is a heat exchanger but thats just where I top up the coolant. Can't see that it serves any other purpose. I didn't know where to get the correct torquing tool so I took the removal of the rocker shaft, etc., route, so as to torque down in the correct order. However, there may be a torquing problem. The workshop manual indicates 71lb psi for most of the nuts and less (somewhere in the the mid 30lbs psi) for some - I think these were the ones that go through the rocker assembly brackets - sorry the manual is on the boat and I'm not there at the moment. My torque wrench is in Newtons so I had to convert to those from Lb psi. I suppose there is a possibility that I got that wrong. However - if that is the problem, I can't understand why the coolant level has barely moved after running the engine for over three hours producing copious amounts of steam for the first half to three-quarters of an hour. Two of those hours were with the engine under load - cruising. I think I need to check whether I've got air in the system once I fully understand how to do that - I refer to my question above about checking the top pipes - still not absolutely clear how I do that. I think I also need to slacken off all the head nuts in order and tighten them down again this time using an old style, Lb psi torque wrench which I've now acquired (its one of those with a pointer and a scale attached to the business end). Or alternatively, if someone knows the correct conversion formula for Lbs psi to Newtons that would be gratefully received. I've found more than one formula online - hence my slight uncertainty. If these things solve it - all well and good. If it improves it but does not solve it fully, I'll replace the head gasket again. I would still very much welcome any further ideas/suggestions. I can't tell you how grateful I am for all your thoughts and observations.

Thanks so much for your replies. The white stuff smells like steam and feels kind of damp - and it completely obliterated the buildings behind the boat. The engine seemed to be running normally. It does have a charging indicator light but it was a very sunny day and I didn't notice it was on until I saw the small amount of steam coming from the thermostat area. Fitting a gauge is on my to do list. It didn't boil up - I stopped before it got that bad. It does have a skin tank. In the process of refitting the head, I removed the stud from the top of the skin tank then filled up with coolant via the heat exchanger until it started pouring out of the top of the skin tank where I'd removed the stud. It took 30 odd litres. I should stress that I'm no mechanic really and I had to learn how to do the work as I was going along which is why it took me about six months to complete the job. (I don't live aboard and I live about 30 miles from where the boat is moored so I can only get to it when time permits.) I've not tried running it with the cap off - I'm assuming that if I try that and I get bubbles, that would be a bad thing? Also - sorry for my ignorance - this is very much a learning process for me and I'm in my seventies - what do you mean by venting the high spots and how do I do it? The only other thing that I can add is that I've had real problems getting a good seal on the rocker box cover, even with a rubber gasket. I think the cover may have a slight distortion. I was planning to sort that out later - so I was running it with a slight oil leak. I don't know if that could be causing a problem.

Hello - I hope someone will be able offer an explanation for this because I'm deeply puzzled. Towards the end of last year I replaced the cylinder head gasket on my BMC 1.5 due to a blue smoke problem. I had the head skimmed by a highly reputable engineering firm then put it all back together. I then started the engine and was shocked to see that the exhaust immediately started producing a massive amount of white smoke. I mean truly massive - so thick that you couldn't see through it. It was the kind of amount that you would expect if there had been a catastrophic head gasket failure and the engine was about to blow up. I can't emphasise this enough - I have never seen so much white smoke. In fact, a small crowd gathered. Probably stupidly, I left it ticking over and the smoking continued unabated for about half an hour. Then, gradually it started to diminish and over the course of about another half an hour it stopped altogether. Again, probably stupidly, I took the boat out and cruised for a couple of hours during which the alternator belt snapped. I have no temperature gauge so I didn't notice at first. Fortunately, I was running with the engine cover open and in the end I noticed a tiny bit of steam coming from near the thermostat housing, so I then realised what had happened, again replaced the belt, and carried on. The next day, forgetting to check the coolant level (I know, I know ...) I started it and it again produced masses of white smoke so I switched it off after a few minutes. Now feeling too despondent to check anything, I decided to walk away and think about it. I've now come back to it today, 2 1/2 months later, checked the coolant level and I find that it has barely moved. So I'm struggling to understand how my engine can be producing that much white smoke with no (or virtually no) loss of coolant (baring in mind any loss associated with the slight overheating due to the belt snapping). Does anyone have any ideas/suggestions, please? My head is getting sore from scratching!

Thanks again for all these further responses. I've still not run the engine since the rocker gasket leak and I'm not back at the boat until next week. I will most definitely step back from the injectors other than taking them off for someone else to look at, if necessary. Same goes for the pumps. At the moment, I can only comment on what was happening before I did the work on the head. As I said earlier, I've done quite a few oil changes and I've never noticed anything unusual about the smell or feel of the oil - including when I checked the dipstick or spotted the leak. I'll examine it more closely next time. Even though it was smoking before, I never seemed to lose much oil - I hope that does not mean I have both oil burning and dilution problems, as suggested above. Someone said I was probably changing the oil so regularly I wasn't noticing it going down. I don't know about that. As far as the rocker assembly is concerned, I completelly dismantled it when I was refitting the head because I was unable to locate a crow foot socket so as to torque the nuts down in the correct order. So I dismantled the rocker assembly, fitted its brackets and torqued everything down in the right order and then reassembled the rocker assembly by sliding the shaft back through the brackets and repositioning the rockers, springs, etc., as I went. It took a while because everything was a tight fit but gentle persitance and patience meant i did not have to force anything. So I was able to have a really good look at its components (using an excellent You Tube video on the subject by Darren Crouch Marine). There was very little wear at either end of the rockers or their centres or the pushrods, come to that. I'm really hoping that I find its a breather issue combined with engine oil thats too thin. On that subject, I have been checking out 20/50 oil on line and trying to get my head around the API ratings. Some of the oils that claim to be made for classic engines seem to have API ratings that indicate they would not be suitable at all. Tony - you recommended I switch to 20/50 - would you be able to recommend a brand ... or anyone else? Lastly - Seadog - many thanks for your kind comments. I'm now over seventy and the boat was supposed to be a retirement project. Trouble is, I forgot to retire 😆. I've done no motor mechanics since I was in my early twenties but I'm now going through life with a set of spanners in one hand and a work diary and laptop in the other. So all your contributions are appreciated at lot more than you may realise!!! Uppards and onnards as they say.

Thanks to all who have contributed on the basis of which my next steps will be to refit the rocker box gasket using glue/silicone and if that doesn't work I'll get a rubber one; check the outlet from the side cover, clean if necessary and attach a hose to a container of some kind; change to 20/50 oil then take it out for a few hours to put the engine under load and heat up that exhaust. If the smoke persists I'll check out/renew the lift pump diaphragm and the injection pump seals (once I've discovered how to do these things); service the injectors (or have them serviced). If the problem still persists I'll have to assume the cause lies deeper in the engine (seized piston rings for example) and I'll have to consider my options. I don't have the facilities or skill set to take out the engine myself and I can't get to the pistons through the sump - not enough room. That may be the point that I have to throw in the towel. Once again - thanks to all.

Many thanks - I'll take look at it. i've often wondered what that outlet was for.

Thanks Stilllearning - no the injectors have not been serviced since I've had it and I'd not thought of that as a possibility. I know I'm inexperienced but I do have a 'have a go' mentality. Is it something I could have a crack at myself or should a professional be involved? Thanks Tony - good point about the oil control rings - sorry I misunderstood the terminology first time round. I'm familiar with the side covers - had to get those off to re-seat the cam followers. Yes - one does have a hose outlet but no hose to the air filter. My air filter is a chrome job - I think they call it pancake style. Is that something I should rectify? Not sure where on the filter it would attach to. Also I didn't notice any baffle or mesh - I clearly need to take another look at that. The cork gasket was sliding all over the place when I fitted it - I'll try the glue idea to the cover side. Thanks for all this. Hi John - thanks for your reply. Not sure I know the difference between the smells. All I know is that its blue. Pre the head work there was enough of it for passers by on the towpath to comment on it. Just before I took the head off I took the boat out for eight hours and it was smoking just as much at the end as it was in the beginning. Obviously, it was only 15 mins idling today before I switched off due to the leak. I will need to take it out for run but we are enjoying typical ... British summer weather now so mechanicking and boating have come to a standstill.

Hi - many thanks for your response - much appreciated. I think I can rule out 1 - 4 because there was no evidence of wear/damage to the bores when the engineer checked them and 5 - 6 because the valves, guides and stem seals are all new and 8 because I'm using Morris Marine 10W - 40 which I understand is recommended for these older engine. I don't do a massive number of hours but oil has been changed five times in the two years I've had the boat. Also 10 - air filter had to come off with the heat exchanger in order to the head off and it was dry. So that leaves 7 and 9. Re 7, do you mean that a leaking lift pump diaphragm or injection pump seals could lead to the oil being contaminated with fuel? Is there any way of checking that and would it be evident in the oil - say - on the dipstick? Re 9 - I don't really know what side chest breathers are. Are they something to do with the tappet side covers - are they checkable/clearable? Before the head was done, the smoke was constant regardless of revs, time running, etc. Started the engine today for the first since the head was done but only ran it at idle for fifteen mins and turned off as soon as I saw the oil seeping from the rocker box. Blue smoke throughout. Only other thing of note was that the engine fired up unexpectedly while I was bleeding the injector pipes. It used to require 25 secs glow plugs - but not today.

Firstly, I'm completely new to engine mechanics so not very knowledgable. I have a BMC 1.5 which started to produce lots of blue smoke some while ago. I suspected a head gasket problem but knew that the problem could also be caused by worn piston rings, worn bores etc. I removed the cylinder head and contacted a local engine rebuilding specialist who is highly experienced and was recommended to me by a narrowboat hire company - so I trust him. He came and checked the bores and said they were in good condition, showing very little wear but that he could see the gasket had gone between the second and third cylinders. He said he didn't think the engine was burning oil in the normally accepted sense but that he thinks oil must have been getting into the second and third bores where the gasket had gone and being blown out through the exhaust. I stripped the head down myself and he skimmed it and confirmed that it had been warped slightly. He fitted new valves, stem seals, etc I then refitted it - with a new head gasket and other bits that needed to be replaced which I got from Calcutt boats, using the workshop manual, various You Tube videos and making a nuisance of myself ringing various companies and asking questions. I then adjusted the valve clearances, bled the fuel system, checked the oil (just above the minimum marker because I've been told not to overfill). By some miracle, the engine started with very little difficulty and ran for about fifteen minutes when I noticed that oil was seeping out from the front end of the rocker box cover on the starboard side. I also couldn't help noticing that the engine is still producing blue smoke - which is a massive disappointment. So my questions are - is it likely that the oil leak is just due to me not getting the cork rocker cover gasket seated correctly? Is it possible that an excessive amount of oil is getting up into the rocker area causing it to leak out under or over the gasket? Is it possible that something is blocked and preventing oil from draining back down into the engine block? Could any of these possibilities result in the continuing production of blue smoke. Apart from the work on the head, I have done all the work myself and I know nothing! Is there anything that anyone can think of that a complete numpty may have done wrong that I could check. All suggestions will be most gratefully received.

Thanks very much everybody. I think I must have dreamed the 12v/240v combination so will put it out of my mind. Its an old boat and I wouldn't be convinced the cables to the fuse box would be up to the job. So - I'll opt for a straightforward 12v fridge which I will connect to the non-battery side of the leisure batteries isolator - once I've found out how that is done! Any suggestions would be gratefully received. PG Yes - I entirely get that - and I found the idea of plugging my boat into a 13amp socket genuinely amusing - so no offence taken or intended. The thing is, you can't learn anything in life without asking questions - and when you first start learning, some of the questions probably will be pretty stupid! Regards, PG

LOL - I may be ignorant but not completely intellectually defict! I do know that shore power doesn't come to the boat via a 13amp plug!!! What I meant was this:- on my boat, there is a shore power inlet (blue, round thing) - but that feeds a 13 amp socket on which someone in the past has helpfully written 'shoreline'. Plugging a 13amp plug into that socket then feeds what I like to think of as a 13amp ring main (i.e., lots of 13amp sockets up and down the boat). Next to the socket marked 'shoreline', there is another which the same person from the past has labelled 'inverter'. If you plug the above mentioned plug into the socket marked 'inverter', the inverter then feeds the 'ring main'. Since you can't plug the plug into two sockets at once, there is no risk of having the shoreline and the inverter feeding the 13amp plugs at the same time. So what I meant is, if you have a two way fridge which can work off either 12v or 240/230v, is it just a case of plugging it into a 13amp socket (which is being fed from the shoreline when the system is plugged into the 'shoreline' plug. Moving on from that, MtB is saying that 12v/240v fridges should be avoided because they wreck batteries. Is this a generally held view? I have read about absorption fridges and that they are not good for batteries but I was talking about a 12v/240v compressor fridge. I have seen a couple of these advertised. Is the general view that it would be better to get a straightforward 12v fridge and a battery charger to harness the shoreline to keep the batteries charged, rather than one of these. My boat does not have a battery charger at the moment. Lastly, the general consensus sxeems to be that the 12v should be connected to the fridge side of the battery isolator. How would one do that (i.e, the practicalities)?, is 6mm cabling okay for a 6 - 7m cable run and should I use a 10amp fuse or something bigger/smaller? Thanks all, PG

Hi - I know very little about narrowboat electrics and what little I do know, I got from this forum. I want to fit a 12v fridge in my boat with the option to run off shorepower when its available. I have been advised not to go through the fuse box but to wire it direct from the batteries. This will involve around a 6-7metre cable run each way - so positve 6/7m to the fridge, negative 6/7m back again. I am planning to use 6mm cable and to include an in line fuse (I believe 10 amp is recommended? - not certain about that) and an in line switch. So - thats the theory ,, however, I am unc;lear exactly where and how to connect the cables to the 12v supply. I have three leisure batteries and a starter battery. Under the engine cover there are two battery isolators. I have no idea what they isolate - one is quite a substantial job with what looks like a stainless steel lever (the bit you pull out to isolate) and the other is more like the standard red plastic job. They are both newly fitted by a highly reputable outfit. I have a suspicion that connecting the cables direct to the leisure batteries is inadvisable - though not sure about that either. But logic dictates that I should be connecting the fridge cables somewhere on the fridge side of one or other (or possibly both) of the battery islolators. So - is that right and, if so, how do you go about connecting the cables? Any advice would be gratefully received. Also, how does the shore power part work on these fridges. Is there just a separate 13amp cable with a plug you can just plug into a socket when shore power is available ... or is it more complicated than that? Thanks in advance PG

Hi all - thanks so much. Once again proving that the helpfullness and supportiveness of the boating community is not at all a myth!!! Regards, GP

Thats a good point - hadn't considered possible wrong feed. Multi meters are my next learning point. Oh dear - really exposing my ignorance now! PG

Apologies - only just spotted the link to Charnleys - many thanks. I'll bear that in mind (and continue to be perfplexed why it didn;t get a hit when I was searching. Actually - just chancing my arm here - the starter is not the knottiest of my problems. Biggest electrical issue is this:- I have 12v to the lights, horn, tunnel light, while the engine is running but that all stops working as soon as the engine is switched off. Meanwhile - the 1500w inverter carries on working - so I have power to all eight sockets in the boat. Meanwhile (again) - 12 v to the water pump does not work whether I have the engine or not. Any ideas wold be gratefully received! Regards, Ian

Hi all - many thanks. Boat is actually a two hour drive away at the moment - hopefully being blacked as we type. So I'm afraid I can't try any of the suggestions just at present. All I can say re availability of the part is that a two hour internet search trying various combinations of 'starter motor solenoid for bmc 1.5 diesel marine engine' threw up absolutely no hits at all. Even the tractor sites (!) that it trawled up were only selling whole new starter motors. Also, I quite like the idea of getting the old one working again - and saving the planet as a useful side-effect! This is all assuming, of course, that it actually is the solenoid or the starter motor that are causing the problem. But - hey ho -, I've got to start somewhere. Thanks again PG

Hi again - engine can be reluctabt to start. Turn key and I just get a click - which sounds like a solenoid problem. Can do that four or five times and then it bursts into life and all is good until the next time I want to start. I suspect the solenoid just needs a clean up and a touch of light lubrication. Ian Sorry - should also have said. I've searched the internet and can only find whole starter motors for sale - no one seems to have just the solenoid any more. Regards, Ian Right - 10mm - thanks - I'll add them to my birthday list (-:)

Many thanks. I'll get a set of AFs then. First job is probably going to be cleaning up the starter motor and solenoid - is that likely ton be AF or BA (for which you said I'd be able to substitute metric). I'm reluctant to buy a whole new starter because I think itm will be a solenoid problem. But you don't seem to be able to obtain just the solnoid anywhere Thanks again, Ian

I'm new to boating and have just bought a 1994 narrow boat. I'm also new to mechanics but would like to do as much of my own maintenance as I can. Could someone please advise what type of spanners and sockets I'll need for a BMC 1.5 engine. I've heard of metric, AF, whitworth (and probably some others I can't recall. Which of these spanner/socket set types will I need to buy for my engine, please?

Hello - I am considering the purchase of a 1989, 45' narrowboat which claims to have a three cylinder, Vetus 3.19 engine. I cannot find any reference to such a power plant anywhere on the internet. Anybody have any ideas, please? Power is said to be '36' - 36 what it doesn't say. Any info would be most welcome, please. Regards, Dr. Polly G

Thats all really useful. Thank you for taking the time. Uhm .... am I likely to recognise a skin tank if I see one!? Where are they located, generally, and how many of them are there? Regards, Ian

At the moment I'm working on limited information - all I have are the brokers boat details. I know neither has central heating. Because of the current situation, I can't view them - marinas tend to be shut and, in any case, I don't go out unless its essential - like we've been told. Hopefully I'll be able to see them at some point and get more info.

Thanks for the advice - I'm one of the world's great preparers - never been known to take a chance on anything - so full service will take place before I go anywhere - especially there!!!

Sorry that should have said 45' with 30 hp.