Ticking in the engine once turned off

[Horsehorn]

Apologies in advance for long post...

 

The end of the story is that when turned off by BMC 1.5 is making a ticking noise that I'm thinking to be contraction sounds of cooling.

 

I have had some cooling problems recently that if hoped I'd fixed. A friend used my boat and reported that it had developed a lot of smoke and they had to pull in.

 

I looked at it and the heat exchanger rubber cap had developed a crack and most coolant/water had escaped. I also saw that the spring in the pressure cap (7psi) looked to have gone, so I've replaced both of these.

 

Today I refilled coolant/water and tentatively ran the engine. It took a little while to start with some white smoke that went pretty quickly (clean filters?).

 

It sounded a little faster than usual and I am nervous to run it for too long in case of overheating.

 

Now the engine has been making some slight ticking noises once turned off, with the ticking noise being more and more spaced out with time. Is this a lag effect of the cooling system being pushing too hard previously?

 

I appreciate there will be more info needed perhaps. and yes, don't lend your boat to friends

 

Is this normal?

 

Thanks

[Guest]

Apologies in advance for long post...

 

The end of the story is that when turned off by BMC 1.5 is making a ticking noise that I'm thinking to be contraction sounds of cooling.

 

I have had some cooling problems recently that if hoped I'd fixed. A friend used my boat and reported that it had developed a lot of smoke and they had to pull in.

 

I looked at it and the heat exchanger rubber cap had developed a crack and most coolant/water had escaped. I also saw that the spring in the pressure cap (7psi) looked to have gone, so I've replaced both of these.

 

Today I refilled coolant/water and tentatively ran the engine. It took a little while to start with some white smoke that went pretty quickly (clean filters?).

 

It sounded a little faster than usual and I am nervous to run it for too long in case of overheating.

 

Now the engine has been making some slight ticking noises once turned off, with the ticking noise being more and more spaced out with time. Is this a lag effect of the cooling system being pushing too hard previously?

 

I appreciate there will be more info needed perhaps. and yes, don't lend your boat to friends

 

Is this normal?

 

Thanks

when my engine started blowing white smoke out of the exhaust, it was caused by water in the fuel. However as you report cooling problems and white smoke simultaneously, I would be thinking along the lines of a head gasket failure. I am sure others will know better than I.

[MtB]

Hard to answer definitively but I'd say ticking sounds can't be much other than things cooling down. Or possibly oil dripping back into the sump.

[Guest]

Hard to answer definitively but I'd say ticking sounds can't be much other than things cooling down. Or possibly oil dripping back into the sump.

A good point. This is very audible on our Vetus, and has been from new.

[MtB]

I'd agree with catweasel, I think your cooling problems are anything but fixed. I don't think the ticking noise is related though.

[Phil Ambrose]

The ticking noise sounds like a cooling down noise as al the hot bits contract slowly back to the norm for cold state. This is not unusual for anything that gets hot, my cooker does this after the oven has been on, likewise radiators will creak and tick as they cool down. I could be wrong (often am)

Phil

ETA your temp gauge should be showing circa 80c, this I understand is about normal.

Edited August 27, 2016 by Phil Ambrose

[zenataomm]

The ticking noise is undoubtably cooling down contraction sounds.

Was it so pronounced before this?

 

If you lost coolant via the rubber cap etc, it possible it then ran so hot the head gasket blew.

If so then your big fear is a warped cylinder head. Without removing it and having it checked by an engineer, you'll not know.

 

Look inside the oil filler cap and at the dipstick for white emulsified gunge, oil and water mixed.

If you have that then it's very likely the head gasket has gone at least.

 

Good luck

[Horsehorn]

Hi, I should have said I'd already checked for head gasket and no signs of white gunk in oil so fingers crossed on that.

 

Catweasel - how do water and fuel fix? Is that a gasket failure?

 

Thanks for help.

[Tony Dunkley]

Today I refilled coolant/water and tentatively ran the engine. It took a little while to start with some white smoke that went pretty quickly (clean filters?).

 

It sounded a little faster than usual and I am nervous to run it for too long in case of overheating.

 

 

You do need to establish whether or not the engine is going to overheat again, and a good way for you to start diagnosing what, if anything, is wrong in the cylinder head area, would be to check the coolant level and then warm the engine up to normal running temperature with the pressure cap off.

 

Whilst it's warming up, adjust the engine revs to minimize the vibration which will be disturbing the surface of the water in the filler neck of the header tank, and watch what's happening to the water, and the level.

 

Small bubbles and/or a trace of fumes/exhaust smell in the filler neck of the header tank are indicative of cylinder head or head gasket problems.

Edited August 27, 2016 by Tony Dunkley

[Guest]

Hi, I should have said I'd already checked for head gasket and no signs of white gunk in oil so fingers crossed on that.

 

Catweasel - how do water and fuel fix? Is that a gasket failure?

 

Thanks for help.

Sort of gasket failure! In my case the silly filler cap on the diesel tank had been leaking (failure of a seal that cost 50 pence, and the gasket between filler fitting and deck.). The water was dragged into the filters and eventually the injectors causing white smoke. We drained and changed the filters, sucked the water from the bottom of the tank with an oil change pump. We then added Fortron to shift the rest of the water. Re bled and off she went. I change the 50p seal regularly now.

 

You do need to establish whether or not the engine is going to overheat again, and a good way for you to start diagnosing what, if anything, is wrong in the cylinder head area, would be to check the coolant level and then warm the engine up to normal running temperature with the pressure cap off.

 

Whilst it's warming up, adjust the engine revs to minimize the vibration which will be disturbing the surface of the water in the filler neck of the header tank, and watch what's happening to the water, and the level.

 

Small bubbles and/or a trace of fumes/exhaust smell in the filler neck of the header tank are indicative of cylinder head or head gasket problems.

Will remember that one.

I think I have seen reasonably priced kits on Ebay that detect combustion products in coolant?

[Tony Dunkley]

 

Will remember that one.

I think I have seen reasonably priced kits on Ebay that detect combustion products in coolant?

 

We've got a Combustion Leakage Detector. It fits into the filler neck and passes air from the small space above the coolant inside the Heat Exchanger/Header tank/expansion tank through a coloured liquid which changes colour in the presence of carbon dioxide.

 

Testing customer's engines with it creates a good impression and gives the appearance of being technically 'up with the times', but truth to tell, I've never yet detected any head or head gasket troubles with it, that I hadn't already diagnosed by watching the coolant surface in the filler neck and sniffing it for exhaust fumes.

Edited August 27, 2016 by Tony Dunkley

[magnetman]

Is it a time bomb

[Guest]

 

We've got a Combustion Leakage Detector. It fits into the filler neck and passes air from the small space above the coolant inside the Heat Exchanger/Header tank/expansion tank through a coloured liquid which changes colour in the presence of carbon dioxide.

 

Testing customer's engines with it gives the impression of being technically 'up with the times', but truth to tell, I've never yet detected any head or head gasket troubles with it, that I hadn't already diagnosed by watching the coolant surface in the filler neck and sniffing it for exhaust fumes.

Interesting. Thanks for explanation.

[Horace42]

White smoke at start-up ould be ignition problems - leaking head gasket - injector wear.

leaking gasket also means you get oil/fuel in the cooling water - you see gungy scum on the dipstick and radiator cap and floating on the cooling water (as already stated by others above).

You also get air forced into the cooling system causing an air-lock - stopping the water flow and hence overheating.

Then the head warps. When stationary water leaks into the cylinders. At this stage you will have trouble starting the engine.

You will need a new gasket, and likely need the head skimmed.

The 'ticking' is characteristic of cooling and normally nothing to worry about - but as you seem to have just noticed it then it points to overheating due to a loss of cooling - that makes it worse.

.

 

[Tony Dunkley]

 

. . . . . . leaking gasket also means you get oil/fuel in the cooling water - you see gungy scum on the dipstick and radiator cap and floating on the cooling water

 

This form of head gasket failure is comparatively rare, and only occurs if the gasket has failed between the oil feed to the valve gear and a water passage, or if there's a severe enough blow to reduce compression to the point where the affected cylinder virtually ceases to fire at all and unburned fuel get forced into the water jackets.

[Tony Brooks]

White smoke on BMC 1.5 of unknown age on start up and for a FEW minutes afterwards may well be situation normal for may 1.5s. As long as the smoke clears and it does not overheat under NORMAL load it is probably OK.

 

I am not saying it is not a head gasket problem but BMCs are known to do this when all is OK. I suspect its when the auxiliary spray hole in the injector nozzle becomse blocked.

 

Certainly do not start pulling things apart or getting paid help until yo have made sure it definitely;y overheats or runs hotter than it used to.

[Horsehorn]

Thanks for your advice all. Going to take another look tomorrow and inevitably call out an engineer to be sure anyway.

[Horace42]

Apologies if I am repeating advice by others - but an easy thing to do is double check that all the cylinderhead bolts are fully tightened.

[Tony Brooks]

 

Apologies if I am repeating advice by others - but an easy thing to do is double check that all the cylinderhead bolts are fully tightened.

 

Far from it on a BMC 1.5 unless the OP has a proper crows foot as per the BMC special tools list or unless you manage to draw the rocker shaft.

 

If the engine is not overheating or otherwise loosing coolant little good will be served apart from the persons bank balance, if you pay someone else to look at it. Its a different matter if there is something other than the smoke just after start up and the ticking that appears to be wrong.

 

If you had asked me to look at it when I was on the tools I would have had to tell you that the smoke could relate to injector problems, timing issues, general engine wear, faulty glow plugs, faulty head gasket, cracked head or block or excess carbon build up. Each of those items would cost you money to investigate and at the end of the day you may be no nearer stopping the smoke. If I had not laid out the possibilities and discussed t with you I could have been held negligent. Now I am only offering advice as a free service I can say that the smoke on starting, clearing in a short while is a known BMC habit and as long as it starts OK and does not overheat can be ignored.

 

I very much doubt the average mechanic around the system nowadays possess the special gauge needed to properly set the timing so most do it by ear.