Cold Coolant Reservoir
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Joined: Jun 2023
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The catch can (reservoir) really only serves to catch fluid which is ejected from the radiator. It then provides a source for the rad to pull/suck from when the coolant in the rad cools. If the reservoir is within the correct fluid level range and the rad is also pretty much full it should be fine. perhaps you don't get the engine hot enough to eject fluid or the rad has an air gap at the top(under the cap) that is sufficient it doesn't need to eject fluid. I think most of the heat on the reservoir is from other engine sources and the fluid in the reservoir is not part of the circulation system, except to catch what is ejected from the rad and permit it to return to the rad when the engine cools.
On Reddit I once gave an explanation about the workings of the coolant reservoir for a CX-5.
https://www.reddit.com/r/CX5/comment...t_low_coolant/
Maybe the coolant reservoir works the same in a Mazda 5?
(the valve is in the radiator cap)
.
I think the operation of the valve and reservoir is as follows:
The valve has a spring that ensures that only at high excess pressure, due to the expansion of the fluid at a high temperature, excess fluid (and possible air) is discharged from the radiator into the reservoir.
When the engine cools down, the fluid (and possible air) in the radiator and motor will shrink and the resulting under-pressure will cause fluid to be sucked from the reservoir through the same hose that extends into the reservoir to slightly below the minimum level (L).
The valve ensures that liquid is only discharged under high pressure, but allows liquid to be sucked out of the reservoir due to low under-pressure.
The above method creates a kind of pumping effect, so that the radiator will always be completely filled, as long as the liquid level in the reservoir is above the end of the hose (else it sucks air).
The reservoir also has an overflow. If the reservoir receives too much fluid from the radiator while the engine is warming up, this will be drained through a small overflow hose to outside the reservoir. Not overfilling above the maximum level (F) with a cold motor will prevent this.
.The valve has a spring that ensures that only at high excess pressure, due to the expansion of the fluid at a high temperature, excess fluid (and possible air) is discharged from the radiator into the reservoir.
When the engine cools down, the fluid (and possible air) in the radiator and motor will shrink and the resulting under-pressure will cause fluid to be sucked from the reservoir through the same hose that extends into the reservoir to slightly below the minimum level (L).
The valve ensures that liquid is only discharged under high pressure, but allows liquid to be sucked out of the reservoir due to low under-pressure.
The above method creates a kind of pumping effect, so that the radiator will always be completely filled, as long as the liquid level in the reservoir is above the end of the hose (else it sucks air).
The reservoir also has an overflow. If the reservoir receives too much fluid from the radiator while the engine is warming up, this will be drained through a small overflow hose to outside the reservoir. Not overfilling above the maximum level (F) with a cold motor will prevent this.
Under normal circumstances there will be little overflow into the reservoir when the engine and coolant heats up. The temperature in the reservoir will increase just a little.
Banned
Joined: Jun 2023
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Actually I am interested in what I've missed while working around these rudimentary systems since they first appeared. I admit to typically working on vehicles of older vintage, 2013 and down but have yet to see sensors controlling or feeding data to the ECU respecting the flow of coolant to/from the reservoir tank. This system is really quite simple!
Also, I certainly don't participate in forums where sarcasm is the norm, which is quite another language altogether. If I somehow stepped on your toes, I apologize, it was never intentional.
Also, I certainly don't participate in forums where sarcasm is the norm, which is quite another language altogether. If I somehow stepped on your toes, I apologize, it was never intentional.
Last edited by hsdejong; Apr 6, 2024 at 05:23 AM.
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Joined: Oct 2018
Posts: 10,665
Likes: 233
From: Northern California
I agree!
On Reddit I once gave an explanation about the workings of the coolant reservoir for a CX-5.
Maybe the coolant reservoir works the same in a Mazda 5?
.
Under normal circumstances there will be little overflow into the reservoir when the engine and coolant heats up. The temperature in the reservoir will increase just a little.
On Reddit I once gave an explanation about the workings of the coolant reservoir for a CX-5.
Maybe the coolant reservoir works the same in a Mazda 5?
.
Under normal circumstances there will be little overflow into the reservoir when the engine and coolant heats up. The temperature in the reservoir will increase just a little.
The proper termer is expansion and contraction of a liquid.
Your explanation was well shall we say "reherced".
As for his borderline discriptive comment I agree wondering if that is what you think he said where it was directed. but never the less in every edjucation there are are those that DIY and those that have a formal edjucation so there will be some that have the knowledge and do not need to run to the internet to find the information and than format it in thier words as if they being the authority on the sugject with experence in thier wording.
If you are going to respond at least read the thread in its entirety also as far as my response if you had read them then you would actually have the means to answer your own question about the Mazda as well most cooling and HVAC systems on vehicles at least ECU controlled ones with OBDII and CANbus from 1995 to present.
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Joined: Jan 2023
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From: BC
Yup, just confirmed nuttier than an Oh-Henry bar. Unfortunate, could have been helpful instead.
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Joined: Oct 2018
Posts: 10,665
Likes: 233
From: Northern California
Maybe I should post with bigger letters (large font size) so you can read at least my responses clearer for a better understanding?
Senior Member
Joined: Oct 2018
Posts: 10,665
Likes: 233
From: Northern California
Not really only your opinion . So the English language and the meaning of words is also a challenge for some? LOL
Hey I am the first to admit my writing skills are less than my mechanical aptitude, but I do know a large number of the 600,000 words (maybe 20k if I actually counted lol ) in the English dictionary and their meaning.
Hey I am the first to admit my writing skills are less than my mechanical aptitude, but I do know a large number of the 600,000 words (maybe 20k if I actually counted lol ) in the English dictionary and their meaning.
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