Breakdown after leaving coolant cap off - what now?

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howlingbaboon
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Breakdown after leaving coolant cap off - what now?

Post by howlingbaboon » Sat Apr 27, 2019 12:51 pm

Hi All,
Had a rough day yesterday. I left the cap off the coolant tank and found out about it after half an hour down the motorway when the low coolant alarm went off. I stopped on the hard shoulder within about 20 seconds but had steam pouring out of the tank. I made the decision to pour about a litre of battery top up water in there (lots more steam and gurgling) but didn't see the water level at all in the tank so stopped and waited (2.5 hours in the rain!) for recovery by which point the side and hazard lights had drained the main battery, another issue... Or several as it turned out, anyway...

The rescue mechanic suggested I should simply top up with coolant mix above max and rev it gently for 10 mins and check the level and said it might spare me a trip to the garage. Firstly do you agree with this advice?

Now I know I put a litre of water in but don't know how much just boiled off (cap was too hot to touch) so I'm not sure how much is in there or how to get the mix right, or even if it matters. Any advice on next steps would be kindly appreciated.
Cheers
Dave
Bob
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Re: Breakdown after leaving coolant cap off - what now?

Post by Bob » Sat Apr 27, 2019 1:09 pm

Hi Dave.

First, which engine do you have?

Second if it's a diesel or V6 petrol ignore the moron.

You will crack the head if it's not bled properly, the 2 litre petrol is self bleeding.

Have a Google for 'You Tube Bongo Bleeding' or similar and have a search on here for 'Bleeding Coolant' and the like.

And don't drive it until it's been bled properly, even if you have to pay for recovery to a Bongo specialist.

Good luck I. 8)
howlingbaboon
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Re: Breakdown after leaving coolant cap off - what now?

Post by howlingbaboon » Sat Apr 27, 2019 2:21 pm

Hi Bob, thanks for the speedy response. It's a V6 petrol.

Ok so bleeding it, is that due to air in the system or something? Sorry I'm not very techy when it comes to cars. Looks like it's a good job I asked on here and a good job I had the coolant alarm fitted.
Bob
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Re: Breakdown after leaving coolant cap off - what now?

Post by Bob » Sat Apr 27, 2019 2:38 pm

Yep, unless it's bled properly there will be an air lock and this will cause damage.

Agree with the coolant alarm, likely saved you a pile of cash.

If you're not confident bleeding it after watching the videos I would suggest recovery to a Bonvo savvy garage. :wink:
howlingbaboon
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Re: Breakdown after leaving coolant cap off - what now?

Post by howlingbaboon » Sat Apr 27, 2019 3:17 pm

Ok, I watched a vid on that before and it didn't look too tricky, shall watch again now. Is it likely to be a problem that we jump started it last night and revved it gently for 10/20 seconds. Sorry if it's a silly question .
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Tony x
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Re: Breakdown after leaving coolant cap off - what now?

Post by Tony x » Sat Apr 27, 2019 4:58 pm

howlingbaboon wrote: Sat Apr 27, 2019 3:17 pm Ok, I watched a vid on that before and it didn't look too tricky, shall watch again now. Is it likely to be a problem that we jump started it last night and revved it gently for 10/20 seconds. Sorry if it's a silly question .
Probably not if the engine was cold
Bob
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Re: Breakdown after leaving coolant cap off - what now?

Post by Bob » Sat Apr 27, 2019 5:02 pm

I'd agree with Tony, and the V6 seems less prone to damage than the diesel. 8)
ognob
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Re: Breakdown after leaving coolant cap off - what now?

Post by ognob » Sat Apr 27, 2019 6:33 pm

howlingbaboon wrote: Sat Apr 27, 2019 3:17 pm Ok, I watched a vid on that before and it didn't look too tricky, shall watch again now. Is it likely to be a problem that we jump started it last night and revved it gently for 10/20 seconds. Sorry if it's a silly question .


Was it a bongo specific video or a generic car one, go careful if generic
howlingbaboon
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Re: Breakdown after leaving coolant cap off - what now?

Post by howlingbaboon » Sat Apr 27, 2019 11:28 pm

Ok, cheers guys, hopefully sounds like I got away with my foolishness then.
Cheers for the concern about the vid, but fear not, it was the very detailed 3 part bongo one.

The video and the pdf instructions I found both refer to a bottom hose under the front of the van. My van has a plastic cover obscuring most of the front underside so I'm not sure if that will need to come off. If I reach in from the front, drivers side, there are 2 hoses which obviously begs the question - which one (if any) is the one I'm waiting to get hot? Maybe they both will...?

Thanks for bearing with me, really appreciate the advice!
ade33
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Re: Breakdown after leaving coolant cap off - what now?

Post by ade33 » Sun Apr 28, 2019 9:52 pm

I watched those videos over and over before bleeding the cooling system on our V6 after replacing a burst radiator.

It was the first job I’d done on it and I was pretty twitchy, having read lots about how quirky the cooling systems are.

Thankfully the task went according to plan and it was fine afterwards.

The bottom hose you’re looking for is the big one off the bottom of the radiator. You may need to remove the small cover panel from below the radiator - I can’t remember if I’d put it back before I bled it.
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