Possible loss of water in Bowman heat exchager on BMC Commander diesel

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NealB

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Our old motor boat has sat ashore, shamefully ignored, for 4 years now (once upon a time, we used to use her mainly as a static houseboat).

5 years ago, both engines were fitted with lovely, shiney, new Bowman heat exchangers, just like the one in this little vid:


I now want to see if both engines will start with their customary ease and reliability, and have been checking things over and bleeding the fuel systems.

Both engines still look clean and neat, and they turn over easily (just for a few seconds).

So........... I'm trying to pluck up courage to see if they'll start.

However, the engines and gearboxes obviously have to slope down towards the stern to mate up with the prop shafts.

So it's quite understandable, even for one with such a simple mind as I, that the antifreeze mix will accumulate towards the rear of the heat exchangers.

In the starboard heat exchanger, the mix is still visible.

However, the port engine's mix has completely disappeared from view. A finger waggled around inside, comes out dry.

There's no obvious signs of any leakage, and I've tentatively tried adding just a little bit more mix, to top it up. I thought about a pint should bring it into view, so went for that.

Result: still no sign of the mix, so I then lost my nerve (sadly, I've never had any delusions of being a competent mechanic).

So .... please ...... what do the forum Gurus advise?

Should I be braver, and just continue adding more mix, till it shows?

Or could it be leaking to unmentionable, and possibly, serious places internally?

Thanks for any thoughts.
 
There are 3 places that water an leak.

External
into the oil
into the cylinder.
into the exhaust

I would check and note the oil level
remove the injectors
disconnect the exhaust
Fill up with water and see it it leaks out or the oil level increased

If no leaks are found and the water level is the same ater say a day or two.

I would then connect up again and stat the engine watching for leaks again and level of water in the heat exchanger.
 
In my view, if it is leaking out into somewhere undesirable then it's something that you are going to have to deal with so you might as well just top it up to the correct level and then see if it goes down and, if it does, whether it just appears in the bilges. If you are conscious of the cost, just top it up with water as you can always replace that with coolant once you know everything is OK.

So, top it up, watch it for 24 hours and, if stays up then start the engine. If it goes down, see if you can see where it's going. Turn over the engine slowly with a spanner as that will tell you whether it's going into the cylinders and check the oil as that will tell you whether it's going there. If it's neither of those then start the engine as nowhere else is that serious.

Richard
 
Is it most likely to be a leak, rather than, say, an ill fitting 'radiator' cap, or slight evaporation over the 4 years of being ignored?

Both heat exchangers were fitted by a trusted, open, ex-RN Marine Engineer, and have only done one trip since being fitted (Limehouse to Burnham via Havengore, 4 years ago).
 
NealB said:
Is it most likely to be a leak, rather than, say, an ill fitting 'radiator' cap, or slight evaporation over the 4 years of being ignored?
Click to expand...

Possibly. I'd fill both engines to the recommended level, then start them individually, and run each for a while (checking for obvious leaks). If you then check the water level and find it's way down, there's a problem somewhere. As you don't claim to be a competent mechanic, it's then time to ask for professional help. You're highly unlikely to diagnose it via forum posts, some posters can't even count. ;)
 
pvb said:
Possibly. I'd fill both engines to the recommended level, then start them individually, and run each for a while (checking for obvious leaks). If you then check the water level and find it's way down, there's a problem somewhere. As you don't claim to be a competent mechanic, it's then time to ask for professional help. You're highly unlikely to diagnose it via forum posts, some posters can't even count. ;)
Click to expand...

Thanks again for your concerns, but, trust me, I have a decent idea of when I'm likely to be beyond my capabilities/ interest in matters mechanical. (y)
 
NealB said:
Haha....... I think Mr Shaw is internally focussed (edit: Gynaecologist as a day job, maybe?)
Click to expand...

No I'm not and never been a Gynaecologist. I find that when you practising a task as a day job takes all the interest out of it as a night job.

Yes I did start considering 3 items but than realised there were 4.

pvb your sarcasm is showing again and with nothing to offer the OP.
 
Rogershaw said:
As I said still nothing to offer except "go a pay someone to do it for you" That's not in the spirit of "Practical Boat Owner"
Click to expand...

I offered a route to help diagnose the problem. Have you read the OP's posts? He's not mechanically-minded, indeed he described himself as a "mechanical numpty". Even "practical boat owners" need to know the limits of their capabilities and use professional help when appropriate.
 
pvb said:
I offered a route to help diagnose the problem. Have you read the OP's posts? He's not mechanically-minded, indeed he described himself as a "mechanical numpty". Even "practical boat owners" need to know the limits of their capabilities and use professional help when appropriate.
Click to expand...

Yes I have read the OP post and I was interested as I have a bowman heat exchanger on my Leyland engine. As it turned out not a heat exchanger that includes the a water cooled exhaust manifold.

I has issues with leaks from my heat exchange with pics of my repair on my web link.

The fact that he states He's not mechanically-minded and has asked for help suggests to me that he is prepared to have a go with so guidance for the forum. If also suggests that he does know his limitations but is prepared to learn.

This IMHO needs and should be encouraged so if a issue arises as sea he will have some knowledge to help him to get solve the issue where he cannot get the provisional to come and do the job.

BTW yes you did offer a route to help but the OP did say he had a look and did not see and obvious signs of an external leak so he had already checked for external leaks which was what your route. Totally pointless.

You picked on my quoting 4 checks but only specifying that I had quoted 3. This is classic Ad hominem

Have a look at what the Department of Philosophy of Texas state university say

Ad Hominem

Have a look at the Debate Pyramid

File:The Debate Pyramid v2 Simple TT Norms Bold Text Outlined.svg - Wikimedia Commons

And Here

https://www.reddit.com/r/Liberteria/comments/dehvpr
 
pvb said:
Why do people from the former colonies become so argumentative?:rolleyes:
Click to expand...

Interesting insultes again and just shows how prejudice you are against any one from " former colonies ". I would call the xenophobia.

More Ad hominem or don't you understand what that means. More likely you don't think it applies to you.

For the record I am English and Born in England from British parents

To be taken you need to get towards the top of the Pyramid of Debate and stop crawling around the base.
 
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