Coolant leak right side (from front)

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BongoBongo123
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Coolant leak right side (from front)

Post by BongoBongo123 » Tue Jun 18, 2019 10:13 am

I was planning to get the hoses done in October (have a full set here, knew they were due) ! Oh well best laid plans. Luckily saved by the Alarm, hit 92C which is fairly safe as I gather. So at least the head won't have gone. Far from ideal mid season.

Bottom hose was cold, top one hot and firm. I guess lost about 1-2 litres of the pink stuff, so a small spill.
I looked in the engine bay and found no signs, just a bit of fluid in the right side battery tray with no fluid on
the expansion tank or cap, just in battery tray. Nothing on the bottom hose but a bit of pink splash here and there
and 1 litre out front on the tarmac.

Cannot see the obvious problem but I suspect bottom hose related (or a joint with either metal pipe or rad) as
the only fluid spotted was that side.

Rather philosophical about it, the way I see it is that temp alarm just saved me £2K !!!

Comes with these vehicles and their old pipes. Not going to do our summer much cop mind you. It is beyond what I can do myself so will be in contact with who might be able to do it in a timely manner. (and the full set of hoses I have of course)

Pffft !
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jimmo62
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Re: Coolant leak right side (from front)

Post by jimmo62 » Tue Jun 18, 2019 11:22 am

I think that if the pressure relief cap operates, the coolant is ejected via the short rubber hose that connects to the expansion bottle near the cap. That would spray coolant onto the leisure battery tray and the passenger side of the engine bay so that could be your problem.

That would indicate over pressure in the coolant system which could be caused by a small air leak allowing air to be drawn in - so would be consistent with your old hoses/joints theory. But it would be worth checking the whole system not just the radiator in case the leak is as above and not at the radiator
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Re: Coolant leak right side (from front)

Post by mikeonb4c » Tue Jun 18, 2019 12:05 pm

BongoBongo123 wrote: Tue Jun 18, 2019 10:13 am I was planning to get the hoses done in October (have a full set here, knew they were due) ! Oh well best laid plans. Luckily saved by the Alarm, hit 92C which is fairly safe as I gather. So at least the head won't have gone. Far from ideal mid season.

Bottom hose was cold, top one hot and firm. I guess lost about 1-2 litres of the pink stuff, so a small spill.
I looked in the engine bay and found no signs, just a bit of fluid in the right side battery tray with no fluid on
the expansion tank or cap, just in battery tray. Nothing on the bottom hose but a bit of pink splash here and there
and 1 litre out front on the tarmac.

Cannot see the obvious problem but I suspect bottom hose related (or a joint with either metal pipe or rad) as
the only fluid spotted was that side.

Rather philosophical about it, the way I see it is that temp alarm just saved me £2K !!!

Comes with these vehicles and their old pipes. Not going to do our summer much cop mind you. It is beyond what I can do myself so will be in contact with who might be able to do it in a timely manner. (and the full set of hoses I have of course)

Pffft !
Was it the low coolant alarm that warned you (if so then presume coolant tank didnt empty and no rebleed needed). Try and observe the system from a cold start (that was how i spotted the leak on my Bongo radiator when it went between the plastic top and metal matrix, but the metal coolant pipe nr tee piece behind drivers seat underneath is another classic candidate, though position of spilled coolant sounds wrong for that in your case). Did you have a new rad when the new head was fitted. Good luck and keep us posted.

P.s. 92deg is v much in normal range I think so may not mean that much. Mine is set to 100deg and STILL goes off after climbing Sutton Bank on a hot day. :lol: So I'm really trying to understand what made you think the coolant level was low before you saw coolant on the ground
Last edited by mikeonb4c on Tue Jun 18, 2019 12:11 pm, edited 2 times in total.
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Re: Coolant leak right side (from front)

Post by BongoBongo123 » Tue Jun 18, 2019 12:09 pm

Thanks Jimmo for that insight. At the moment I have put a call into Allans and I suspect he is on the busy side so also
had a word with Mazda Bongo. As I have spoke to Allans before I want to be fair about the hoses change and give him
first option but have another Bongo place who understands with this approach ready.

Allans' is great of course but very far from us and he is a busy chap so I am trying to keep calm and await a call back.
Fingers crossed he calls at lunchtime. Other place has a 2 week wait which is kind of good as we have some journeys
planned early July.

All will be well somehow I am sure.

It was the head temp sensor alarm Mike (we have no low coolant alarm)
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Re: Coolant leak right side (from front)

Post by mikeonb4c » Tue Jun 18, 2019 12:14 pm

BongoBongo123 wrote: Tue Jun 18, 2019 12:09 pm Thanks Jimmo for that insight. At the moment I have put a call into Allans and I suspect he is on the busy side so also
had a word with Mazda Bongo. As I have spoke to Allans before I want to be fair about the hoses change and give him
first option but have another Bongo place who understands with this approach ready.

Allans' is great of course but very far from us and he is a busy chap so I am trying to keep calm and await a call back.
Fingers crossed he calls at lunchtime. Other place has a 2 week wait which is kind of good as we have some journeys
planned early July.

All will be well somehow I am sure.

It was the head temp sensor alarm Mike (we have no low coolant alarm)
The head sensor alarm cant tell you directly that you've lost coolant, and 92degrees is not an unusually high temperature. So I'd like to understand how you knew, before removing the expansion tank cap, that you'd lost coolant. Had you seen some on the ground already? Sorry to appear pedantic! And personally, i would fit an LCA as its better to know about coolant loss before temp starts rising (an indication the expansion tank might be empty, air is now in the system, and it'll have to be bled before driving on rather than just topped up)
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Re: Coolant leak right side (from front)

Post by BongoBongo123 » Tue Jun 18, 2019 12:20 pm

Thanks Mike yes....1-2 Litres of coolant was on the ground/ passenger side just under the bumper. Once I saw the alarm hit its
92C threshold (lucky I was literally parking up outside my house !) I had a look around and there was the coolant
on the ground, not loads but some estimate 1L or so.

Nothing in the engine bay, or around the Turbo pipes etc.

1/4 a cup worth in the battery tray.. and a little on the rubber top hose but further down/in than
where it attaches to the rad. (and we had a new rad so that should in theory be ok, not very old 3 years or so)
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Re: Coolant leak right side (from front)

Post by mikeonb4c » Tue Jun 18, 2019 12:26 pm

BongoBongo123 wrote: Tue Jun 18, 2019 12:20 pm Thanks Mike yes....1-2 Litres of coolant was on the ground/ passenger side just under the bumper. Once I saw the alarm hit its
92C threshold (lucky I was literally parking up outside my house !) I had a look around and there was the coolant
on the ground, not loads but some estimate 1L or so.

Nothing in the engine bay, or around the Turbo pipes etc.

1/4 a cup worth in the battery tray.. and a little on the rubber top hose but further down/in than
where it attaches to the rad. (and we had a new rad so that should in theory be ok, not very old 3 years or so)
I'm just a little concerned in case its overpressurisation that is the cause. But best wait and see what the mechanic says. But if the top hose gets v firm v quickly from cold start i believe that is significant (perhaps our techies could comment as i'm no expert).
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Re: Coolant leak right side (from front)

Post by BongoBongo123 » Tue Jun 18, 2019 12:31 pm

Correction ( No nothing on the top hose !) That is on the other side.

In fact I just had another look and there is no fluid on any hose or joint with rad.
Nothing at all on expansion tank only in battery tray.

There is fluid on the crossmember and "shelves" either side of the rad, just a bit (and its support which is a beam facing forwards) and
a bit on the bottom of the rad (looking from undernetah) plastic bit (under). Bottom hose looks dry as a bone..as does the metal
pipe further in with the clip on that the top hose connects to.

I think it is not major which is good and head should be fine at 92C (thankful for small mercys)

But whatever it is I am going to get the hoses done etc. etc. that was planned for later in the year.

Shame it could not have waited a few months. :lol:
Last edited by BongoBongo123 on Tue Jun 18, 2019 12:33 pm, edited 1 time in total.
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Re: Coolant leak right side (from front)

Post by BongoBongo123 » Tue Jun 18, 2019 12:33 pm

Was just a 3 mile gentle journey to supermarket and back, lucky it happened outside house and
not in supermarket car park really. There are things to be thankful for.

And yes top hose was firm and hot when I touched it post leak.
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Re: Coolant leak right side (from front)

Post by mikeonb4c » Tue Jun 18, 2019 12:50 pm

BongoBongo123 wrote: Tue Jun 18, 2019 12:33 pm Was just a 3 mile gentle journey to supermarket and back, lucky it happened outside house and
not in supermarket car park really. There are things to be thankful for.

And yes top hose was firm and hot when I touched it post leak.
All sounds "good" with luck. And personally i have had the LCA save me a few times when i had a leak. I'm not sure i'd rely on the engine temp alarm for that though its a useful thing. An LCA may not cover all situations, but its great for straightforward coolant loss warning. :wink:
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Re: Coolant leak right side (from front)

Post by BongoBongo123 » Tue Jun 18, 2019 1:03 pm

This is why I have the threshold so low. I think the fiddly nature of the low coolant alarm
(drilling holes in expansion tank) puts some including myself off a bit.

I cannot quite get my head round why there is fluid in battery tray yet no where else
to be seen on the header tank itself/pipes to/from it. #-o Must have been a stray squirt from somewhere lower.
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Re: Coolant leak right side (from front)

Post by BongoBongo123 » Tue Jun 18, 2019 1:09 pm

Jimmo was right I think, sorry the stress is making me not think straight..yes the small rubber hose
from the cap does have a drip of coolant still on it so overpressure somehow seems to be the reason.

Given all the connections seem dry. Making notes of all this to hand over to whoever repeairs it.
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Re: Coolant leak right side (from front)

Post by g8dhe » Tue Jun 18, 2019 2:04 pm

Have you checked the top of the radiator, the plastic to metal joint is often a source for radiator failure and there isn't much other pipework that can cause coolant to fall on top of the crossmember itself and the areas either side.
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Re: Coolant leak right side (from front)

Post by BongoBongo123 » Tue Jun 18, 2019 3:21 pm

Thanks Geoff..Rad is just 3 years old so in theory should be ok, only do about 4/5K miles a year. I did not see
anything but will quickly double check. I suspect that it coolant coming from the header tank dropped 1 litre
or so into the tray which but to be honest don't know.

One thing for sure when they go wrong it is not a fun process making rather stressful decisions.

Just trying to remain calm.
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Re: Coolant leak right side (from front)

Post by BongoBongo123 » Tue Jun 18, 2019 3:27 pm

Rad top and plastic parts all seem dry. Most likely dumped water into battery tray from the little tank cap hose and went over or
seeped out of tray onto the forward facing beam and then down to upright sides of crossmember. (and shelves)
(was very little on actual horizontal lower crossmember)

It seems quite a small leak but certain enough to send it out of my normal mid 80's temps.
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