Clubjazz - Honda Jazz & HR-V Forums

Honda Jazz Forums => Honda Jazz Mk4 2020 - => Topic started by: ninanina on February 11, 2025, 04:27:09 PM

Title: Coolant Level
Post by: ninanina on February 11, 2025, 04:27:09 PM
I’ve checked my oil and coolant levels today

Oil is up to the maximum level on the dipstick so is perfect

I’m just not sure on the coolant level as it’s quite difficult to see exactly where the level should be

Can anyone take a picture of their coolant expansion tank for me?

Title: Re: Coolant Level
Post by: ahavoja on February 11, 2025, 04:59:43 PM
Is this the correct tank? It looks like it has two lines. The lower line has "Min" written next to it. I've marked it with red on the photo. The upper line (marked with green on the photo) has "Max" written next to it on the other side of the tank. I suppose the coolant level should be between these two lines.
Title: Re: Coolant Level
Post by: coldstart on February 11, 2025, 05:08:41 PM
....

I’m just not sure on the coolant level as it’s quite difficult to see exactly where the level should be

Can anyone take a picture of their coolant expansion tank for me?

What about our answers in this thread (started by yourself only a fortnight ago)?
https://clubjazz.org/forum/index.php?topic=17370.0

(now I'm a bit confused ...)

Title: Re: Coolant Level
Post by: ninanina on February 11, 2025, 06:57:09 PM
I’m also a bit confused as the level seems very low down in the tank

I can’t see MIN or MAX marked on the tank either
Title: Re: Coolant Level
Post by: ahavoja on February 12, 2025, 12:31:23 AM
The MIN and MAX text markings are indeed not very visible. I needed to use a torch to see them. Also the MIN marking is on another side of the tank than the MAX.
Title: Re: Coolant Level
Post by: coldstart on February 12, 2025, 05:26:21 AM
I’m also a bit confused as the level seems very low down in the tank

I can’t see MIN or MAX marked on the tank either

Please define "very low down".
Do keep in mind that the MAX marker is a little below the middle of the reserve tank!

The reserve tank is used to compensate for the expansion (and contraction) of the coolant during operation and stand still, so there has to be some room left!

You are right:
There is only the MIN lettering visible near the bottom line on my car. The MAX line has no visible markings on the same side as MIN.

As mentioned in your previous thread (https://clubjazz.org/forum/index.php?topic=17370.0) (and the fine manual on p522) the correct level upon refill is up to the MAX mark in the middle of the tank.


Title: Re: Coolant Level
Post by: Lord Voltermore on February 12, 2025, 09:41:24 AM
Maybe the confusion is because there are two expansion bottles.  Not sure why but I think its because Honda use a slightly different system to most cars that is more common on liquid cooled motorcycles.

On the larger one to the left  the coolant level is fairly obviously darker  on my car .  About halfway between the min and Max lines.  .  Once you realise the correct level is well down the bottle I find no difficulty in checking it. . I hadnt realised the max line is indeed marked as max  but on a different side of the bottle

The photo was taken when the car is cold . Weather about +5 C.  The car is on a bit of  a slope.  I think this level is about right ,but will keep an eye on it.  :-\

The second bottle  is near the battery. . The min and max line are close together  and the bottle is more or less full.   It has a pressure cap.  I may check the level is OK but wouldnt attempt to top this one up myself.
Title: Re: Coolant Level
Post by: Steve_M on February 12, 2025, 10:10:55 AM
That smaller coolant reservoir is for the hybrid system and not the engine cooling system, it cools the power invertor etc.
Title: Re: Coolant Level
Post by: ahavoja on February 12, 2025, 10:35:23 AM
And I might add that electronics work better when they stay cool, whereas combustion engine works better after it has warmed up. This might be why there are two separate cooling systems, to maintain two different temperatures.
Title: Re: Coolant Level
Post by: ninanina on February 12, 2025, 05:19:28 PM
Thanks to everyone for their help, much appreciated

As I was a bit worried about my coolant level in the expansion tank I popped into my local Honda service centre for a quick check up. I’m lucky that they are a couple of minutes from me

I now realise my slight mistake; what I thought was just a series of lines marked near the bottom of the expansion tank actually says ‘MIN’ written (North to South) on it’s side and the groove further up the tank is the Maximum marker. Both markers are quite low in the tank; within the bottom third of the tank

My coolant was above the MIN mark but the dealer added a ‘splash’ of coolant to bring it up nearer to the Maximum level groove for me

No charge and I was very impressed with their service

I’ve added a couple of pictures of my expansion tank now;  Blue circle is the Minimum line and yellow circle is the Maximum line groove

Title: Re: Coolant Level
Post by: ninanina on February 12, 2025, 05:42:16 PM
Is this the correct tank? It looks like it has two lines. The lower line has "Min" written next to it. I've marked it with red on the photo. The upper line (marked with green on the photo) has "Max" written next to it on the other side of the tank. I suppose the coolant level should be between these two lines.

Yes you are spot on

Thanks for your help
Title: Re: Coolant Level
Post by: coldstart on February 13, 2025, 03:16:45 PM
@ninanina

You are right again! The image in the manual is somewhat misleading:
Actually, the MAX mark is in the lower third or even quarter!
(I've just taken a closer look at the tank in my car...)

Sorry about the confusion I may have created  :-[
Title: Re: Coolant Level
Post by: Lord Voltermore on February 13, 2025, 04:50:47 PM
Now 4 of us have posted photos of our expansion tank I am a  bit concerned that 3 are filled to the max line. Mine is only half way between min and max.   :-\

I think it  was a similar level  when delivered new in September 2024.  I assumed it was the normal factory fill level. Within  an acceptable range rather than max being the norm.   Its not yet had its first service. Maybe they check the level and top it up then.

The handbook says top up if it falls BELOW min. Topping up to max then makes sense.  But I would be concerned  if the level dropped that significantly . None of my previous few cars ever did. 

I normally check levels when I top up the  screenwash but will do so more often for a while.
Title: Re: Coolant Level
Post by: coldstart on February 13, 2025, 05:41:42 PM
Now 4 of us have posted photos of our expansion tank I am a  bit concerned that 3 are filled to the max line. Mine is only half way between min and max.   :-\
Never mind! - Mine was only "recently" (late August 2024) serviced and I'm positive they would have topped it up if necessary!

Title: Re: Coolant Level
Post by: Tombola on February 13, 2025, 07:41:13 PM
Mine is filled to the MAX line
Title: Re: Coolant Level
Post by: Lincolnshire Rambler on February 14, 2025, 04:32:31 PM
In reply to LV my coolant level is halfway with a cold engine - i havent looked when hot !
Title: Re: Coolant Level
Post by: ninanina on February 14, 2025, 05:13:32 PM
I was a little concerned about my coolant level as it seemed so low down in the expansion tank and I initially couldn’t see the MIN & MAX markings

It makes a lot more sense now I know how low down in the tank the MIN & MAX lines are

Anywhere between MIN & MAX is perfectly normal and nothing to worry about

I only got it double checked by Honda as I have a long drive coming up next week