Coolant alarm problem

[Northern Bongolow]

Weekend is probably best, see how it goes after a accurate batt test. Shout if you need.

The low coolant alarm is actually telling you something, but only Haydn speaks the coolant alarm language. Over the 10 years we had our bongos I loved ours, never any false alarms, 2 real alarms after a water pump failure, and a pipe leak. I fitted about 10 to other people's without issues. You can even use them to bleed the coolant system using the seesaw method to listen for the level in the expansion tank, I fitted the high level add-on that Haydn made in limited numbers, this helped you bleed the system with your eyes closed.
I noted that occasionally I did repairs to the Lecky systems on bongos that accompanied coolant alarm squeals or activations,these were usually related to low voltages seen at the alarm wherever it was taken from,usually an ignition switch live as advised.
Alternator problems, battery issues or glow plug or circuit/relay etc are the usual.
After the starter battery has started the engine particularly in harder to start colder months when the glow plugs can be on off for quite a while, the starter battery is recovering from the starting hammering it's just had, the alternator may also be slow to up it game, the lights and wipers go on, the Aircon demist goes on is it hard to imagine the voltage seen at the low coolant sensor may dip slightly, this dip is not as evident when the glow plugs are fresh and the alternator is quick to up its game etc. I always listened to the coolant sensor as it was telling you something was not quite right.
I'm not related to Haydn, or have any connection to jo, I have used their alarms for years without any gripps, they do have their limitations but they are an aid and nothing more, with a bit of common sense they are the best I've found to do the job.

Ps. Haydn, I will pm you my address for the Xmas card. Lol.

[haydn callow]

I’ll put your commission in with your card same as every year. Regards to all ‘up North’

[mikeonb4c]

Nice post Ady. Mine chirps false occasionally and i've taken the same view as you when it does. Hopefully the OP will track the source. Is it also fair to say this type of LCA design stems from the (Aussie) days of ethylene glycol antifreeze, so that the newer OAT antifreezes present extra challenges?

[TheLongRoad]

In a thread a while back relating to me replacing the steel pipes and doing away with the rear heater, I reported I'd used OAT antifreeze in our 2.0 ltr petrol. When I first filled up the header tank with the 50/50 mix, on starting the alarm sounded for about a minute - since then it has performed without fault. My experience is the OAT makes no difference. Tempted to add a LCA to my car as well.

[haydn callow]

Hi, yes, it’s only a particular type of Oat antifreeze that ‘can’ cause problems. If it’s going to cause problems than it will affect any make of alarm that works on the same principal as our alarms....the alternative would be a float type alarm and they have many much worse problems.

[haydn callow]

If you want one for your car, phone Jo at mission control and ask for ‘dad’s discount’

[mikeonb4c]

Hi, yes, it’s only a particular type of Oat antifreeze that ‘can’ cause problems. If it’s going to cause problems than it will affect any make of alarm that works on the same principal as our alarms....the alternative would be a float type alarm and they have many much worse problems.

My thoughts exactly. I'm a glycol man anyway - call me old fashioned but it might well be what was the default choice when my old diesel lump was conceived by designers.

[TheLongRoad]

If you want one for your car, phone Jo at mission control and ask for ‘dad’s discount’

Thanks, very kind.

[Two R's]

Not used the Bongo for a few days as I’ve had this lurgy that’s going around.
Tested the battery this morning.
Before starting : 11.6
After ten miles with engine running 13.7

I noticed glow plug light took a few seconds to come on when I turned ignition on and it was a very lumpy start.

I let the engine run for a few minutes. The alarm was sounding the whole time.

Just after setting off it stopped.

Over the next ten miles it came back on 5 or 6 times, mostly when I was stationary or in slow traffic.

I’ve a few little jobs to do on the van so will boo it in with my local garage before the weekend to see if he can test and replace any dud glow plugs and get a third opinion on the battery!

If I can’t get booked in before the weekend I’ll get in touch with Northern Bongolowand and head over to Colne.

[g8dhe]

You tested the battery before starting as being at 11.6 volts this is well down, a fully charged battery will measure 12.6 volts when resting - i.e. no charging or discharging for 30 minutes or so.
Lumpy start and poor running not surprising with a battery that was low already and has now had the rest of its charged used to start turn the starter motor and run the glowplugs.
After ten miles and with the engine running you measured the Alternator output voltage as being 13.6 volts, that's correct for the alternator at tickover, you didn't measure the battery voltage as such merely the charging voltage.

[haydn callow]

11.6 is a dead battery ..... the alarm will not like that....and 13.7is not a good charging voltage but that could be down to a duff battery......as suggested right at the start of this topic......you need a new battery

[Two R's]

You convinced me then, but I’ve tried to get a new battery - twice since.
These are the read outs from the first trip to Halfords.
https://www.dropbox.com/s/0lawcc6bokauy ... 4.JPG?dl=0

As mentioned before, I was bewildered by this and wondered if they’d read the batteries the wrong way round as my leisure battery was fully charged when I got home.

I’m booked in to my local garage for Tuesday morning for battery and glow plug test.

I also need them to fix the damn reversing camera that doesn’t work so might as well try kill 3 birds with one stone.

[Two R's]

My local mechanic got back to me today to say the battery and glow plugs are all fine. He asked me if I wanted to disable the alarm. Before I do this, is there anything else I need to check? I want this alarm to work purely for low coolant and nothing else, otherwise I can’t trust it and I need to look at better options. After several opinions I’d rather invest in something like an engine temperature alarm than spend double on a new battery and risk getting the same false alarms.

[Northern Bongolow]

Get a second opinion would be my advice. Or a third or fourth.

[haydn callow]

If you want to send the alarm back to us we will replace it with a new one for you to fit...we will then check out the returned alarm and report back....all FOC