[IndigoXLGrandDi]

If there is no Radiator Cap, one has fill coolant in the expansion tank itself.
Our Indigo for one also does not have radiator cap and needs coolant to be filled from expansion tank only. As the expansion tank level is on higher side, the coolant will flow into the radiator and will fill the latter. When all the pipes, radiator will get filled, the level in the expansion tank will also increase.

[sandeepmohan]

Originally Posted by wanderernomad

My normal temperature indicator is not working but when I switch on the AC the temperature reading starts to work.

You need to get this checked asap. The sensor is surely malfunctioning.

[wanderernomad]

Originally Posted by IndigoXLGrandDi

If there is no Radiator Cap, one has fill coolant in the expansion tank itself.
Our Indigo for one also does not have radiator cap and needs coolant to be filled from expansion tank only. As the expansion tank level is on higher side, the coolant will flow into the radiator and will fill the latter. When all the pipes, radiator will get filled, the level in the expansion tank will also increase.

This means if my reservoir is empty and it took only say about 500 ml to fill it up again, I have enough coolant in the radiator to not worry about having driven on an empty reservoir?

[IndigoXLGrandDi]

Originally Posted by wanderernomad

This means if my reservoir is empty and it took only say about 500 ml to fill it up again, I have enough coolant in the radiator to not worry about having driven on an empty reservoir?

You got it wrong or wasn't I clear enough?
There are Min/Low and Max/High markings on the Expansion/Auxiliary Tank. The Coolant should always be between "These" Two Markings. Please do not add coolant above Max/High Marking.

[Mortis]

When I sent my Beat for Servicing, the advisor noted that the coolant level was low and that there might be a leak. I hadnt noticed any overheating problems prior to that or any visible signs of leakage so I assumed that he is trying to pull a fast one and asked him to top up and return the car I will get it checked at

On getting the car back I did notice that the coolant level was low, almost at the neck of the coolant overflow chamber. Please note that the Beats radiator is sealed and doesnt have a cap, access is from the overflow chamber only which has a pressurized cap.
I refilled to the Max line with distilled water, closed the cap and left it overnight. I checked it the next day and there was no sign of coolant below the car or anywhere in the engine bay. Drove the car normally and checked again once it cooled and coolant level had reduced. Ive been topping and checking the car regularly and it seems that the following is confirmed :

1] Coolant level stays the same when car is unused
2] It reduces when the car is driven although no visible leakage is present around the engine bay

Some online research pointed me towards the coolant reservoir cap as being a common cause for coolant loss. The steam escapes from the cap slowly. There is some condensation of coolant on the rim of the coolant bottle which has a rim at the Min level marking. There is also an overflow vent tube near the neck pinting downwards towards this rim. When I went searching for the cap a parts shop indicated its a common problem with Chevy cars.

I also checked the oil for milkyness and exhaust for white smoke to indicate internal leakage. Both were absent.
My FNG also couldnt note any signs of internal leakage but is unsure if it is the cap. He tightened some hoses and the cap and asked me to see if it makes a difference or else he will try to 'delete' some part of the coolant circuit for testing (Im unsure what he meant but I trust his work). The above didnt make any difference, coolant was still lost.

Im unsure how to proceed. Im leaning towards the cap still but it cost 1000 bucks for just the cap so I dont want to buy it without having atleast a good suspicion that it is indeed the cause for the leak. It could be a pin hole also somewhere that leaks extremely slow when the car is off but increases when the car is running but I kind of doubt it. So far the coolant level hasnt gone below the lowest point in the reservoir and I havent allowed it to, should I see how much further it goes down ?

Please advise me on how to proceed and confirm the cause of the leakage.
Also please point me to a guide on refilling coolant in a system like this which doesnt have a reservoir cap. I will be doing a flush and changing the coolant since I have topped off atleast 2.5 lts of water during my testing

[arunphilip]

Originally Posted by Mortis

My FNG also couldnt note any signs of internal leakage but is unsure if it is the cap. He tightened some hoses and the cap and asked me to see if it makes a difference or else he will try to 'delete' some part of the coolant circuit for testing (Im unsure what he meant but I trust his work). The above didnt make any difference, coolant was still lost.

You've ruled out the common and more worrying causes like a cracked head by checking the oil and exhaust. So that's a relief.

Do you know someone else with a Beat for you to switch the coolant reservoir cap, for testing purposes?

Do you notice any condensation on the inside of your windshield in your car when it is running? Another area where leaks can happen is in the heater core (heater matrix) beneath the dashboard. This brings in engine coolant into the heater core (it looks like a small radiator) and uses the coolant's heat to warm up the passenger compartment. If you have a leak in this core (due to bent fins, rusting, etc.) then it will lead to slow loss of coolant, and will manifest as condensation on the inside of the windshield (particularly the lower part) or damp floor carpets in the front centre or front passenger side.

I suspect this is what your FNG was suggesting - because you can bypass this heater core by removing the tubes going to the heater core and joining them together.

EDIT: Added responses

Originally Posted by Mortis

Aah sorry as usual I forgot a point in typing out the post. No condensation or any signs of internal leaks.

OK, then your suspicion of the cap is very reasonable, particularly given the absence of leaks inside or below the car. Those caps do tend to jam or clog. Just try seeing if there's any cleaning you can do, blowing, to remove any dirt.

Originally Posted by Mortis

There is a couple renting a flat in the building who have a Beat. Ill approach them to check but since I dont know them too well it will be a slightly awkward conversation :P

I can sympathize. Try asking the gent to join your investigations to show you have no devious plans, and if he's of a technical sort he'll be interested

[Mortis]

Originally Posted by arunphilip

You've ruled out the common and more worrying causes like a cracked head by checking the oil and exhaust. So that's a relief.

Do you know someone else with a Beat for you to switch the coolant reservoir cap, for testing purposes?

Do you notice any condensation on the inside of your windshield in your car when it is running? Another area where leaks can happen is in the heater core (heater matrix) beneath the dashboard. This brings in engine coolant into the heater core (it looks like a small radiator) and uses the coolant's heat to warm up the passenger compartment. If you have a leak in this core (due to bent fins, rusting, etc.) then it will lead to slow loss of coolant, and will manifest as condensation on the inside of the windshield (particularly the lower part) or damp floor carpets in the front centre or front passenger side.


I suspect this is what your FNG was suggesting - because you can bypass this heater core by removing the tubes going to the heater core and joining them together.

Aah sorry as usual I forgot a point in typing out the post. No condensation or any signs of internal leaks.

There is a couple renting a flat in the building who have a Beat. Ill approach them to check but since I dont know them too well it will be a slightly awkward conversation :P

EDIT : I just hope that their cap is working fine, since their car is older than mine ! I guess if their coolant levels are ok I can assume their system is all OK and all parts are functional.

Thanks arun I will update the thread when I have tested this out. A topup, swap and 10-15min drive should tell me if it is the problem.

[Mr.Boss]

Originally Posted by Mortis

Some online research pointed me towards the coolant reservoir cap as being a common cause for coolant loss.
....
When I went searching for the cap a parts shop indicated its a common problem with Chevy cars.

True it is.
We went mad with the same issue on a Chevy Spark (belong to my friend) but our case is little different. It had physical leakage (at radiator and heater core) and once that was addressed we figured out the reservoir cap. Got one used cap free of cost fitted in the car and it works like a charm now.

[myavu]

Originally Posted by Mortis

When I sent my Beat for Servicing, the advisor noted that the coolant level was low...

Mortis, I am also facing the same issue with my Beat for last 2 years. Just living with it by topping the coolant container with Bisleri once in a month and coolant once in 4 to 5 months. I normally top the fluid when the level of it reaches around 1 cm over minimum mark. Metro Service don't have an answer to this. As you mentioned the coolant is just disappearing.

What I had noticed is that if I keep on adding water only, the loss is at higher rate i.e around 30 days. (from maximum mark to 1 cm over minimum mark) but if I top it with coolant once in 4 months the overall loss is extended to approximately 2.5 months.

Me too searching for answers, even though it is not that serious issue as far as I am concerned.

Cheers!

Vinu

[Mortis]

Originally Posted by myavu

Mortis, I am also facing the same issue with my Beat for last 2 years. Just living with it by topping the coolant container with Bisleri once in a month and coolant once in 4 to 5 months. I normally top the fluid when the level of it reaches around 1 cm over minimum mark. Metro Service don't have an answer to this. As you mentioned the coolant is just disappearing.

What I had noticed is that if I keep on adding water only, the loss is at higher rate i.e around 30 days. (from maximum mark to 1 cm over minimum mark) but if I top it with coolant once in 4 months the overall loss is extended to approximately 2.5 months.

Me too searching for answers, even though it is not that serious issue as far as I am concerned.

Cheers!

Vinu

I guess yours is a smaller leak. Mine goes from max to below min mark in about 10Km drive so I was topping up daily before taking the car out. This is too convenient so Im trying to figure out the cause. You can also maybe give it a shot by borrowing a fiends coolant cap and using it for a while if you get a chance. If it isnt the case and its a tiny leak then you could fix it by using a radiator seal additive.
BTW did you manage to fix your chipping gear knob ? I did a jugaad fix for mine and im pretty satisfied with it. I stuck back the chips with superglue, filed off the excess glue and then coated the knob with 4 coats of Plastidip. Its holding up fine after 2 months.

[myavu]

Originally Posted by Mortis

BTW did you manage to fix your chipping gear knob ? I did a jugaad fix for mine and im pretty satisfied with it. I stuck back the chips with superglue, filed off the excess glue and then coated the knob with 4 coats of Plastidip. Its holding up fine after 2 months.

Yes, me too glued whatever chips I could gather from the floor and cup holder. But ultimately I am going to change it along with the clutch. I had met couple of Beat Petrol guys from early 2010 batch last week at Metro when I went there for changing the brake light switch and to rectify High tone horn not working (changed it last June). All those guys' gear knobs are chipped badly. SA had informed that many had replaced it paying the ridiculous price (2000 + tax).

Cheers!

[Jaggu]

Originally Posted by Mortis

I guess yours is a smaller leak. Mine goes from max to below min mark in about 10Km drive so I was topping up daily before taking the car out.

That is a lot of leak, if you don't see any residue at the filler cap (it will show even if its steam thats escaping, if it is coolant) or hose joints etc, then one thing you need to check is your water pump. See if there are any signs of leakage there, which can go unnoticed since it will evaporate with engine heat. Only severe leaks migh cause dripping from water pump.

[Mortis]

Originally Posted by Jaggu

That is a lot of leak, if you don't see any residue at the filler cap (it will show even if its steam thats escaping, if it is coolant) or hose joints etc, then one thing you need to check is your water pump. See if there are any signs of leakage there, which can go unnoticed since it will evaporate with engine heat. Only severe leaks migh cause dripping from water pump.

There is dampness on the threads and inside of the filler cap. There is also a rim in the middle of the coolant bottle which serves as the Min level. This also had coolant on it which also pointed me towards the cap as being the source of the leak as coolant evaporates and condenses in outside air then part of it flows down along the reservoir and settles on this rim.

BTW I hadnt come across any overheating issues or noticed coolant loss before it went to the A.S.S. for servicing. In fact I was running Torque the week before and coolant temps were hovering in the normal 95ish degree area throughout.

[Mortis]

UPDATE :

Got a chance to go for a 50km round trip yesterday and observed the following :

1] Coolant level doesnt seem to drop below the lowest point in the coolant reservoir. I havent allowed it to drop below this though

2] After returning I checked under the hood. There was condensed water on the outer rim and also it was dark and I was using my phone torch, I noticed for the first time a couple of dried drip stains of the orange coolant dye from the cap to the bottom of the reservoir.

This is leading me towards my initial assessment that the cap has failed.

I managed to swap the caps with my neighbours Beat ! But as my luck would have it and I sort of foresaw it, theirs being an older car, they too were having cooling system issues and it seems to be the same as mine. Coolant reducing, no puddles at standstill, no visible leaks, no white smoke.
Still, I swapped caps and went for a 7-8km drive at various speeds and with a couple of stops in between.
Sure enough the coolant still reduced but at a lesser amount than with my cap, it reduced from Max halfway to Min. Mine would have dropped past this.

I think Ill go ahead and replace the cap now with a new one. Ill check it out and then do a radiator flush and replace my coolant. Maybe Ill drop in some radiator leak sealant in for good measure.

Any good online shop for Chevy spares ? Local shops quoted approx 1100 for it, one guy quoted 2K !

Also my neighbours Beat also had the rubber coating chipped off from their gearknob ! It seems the Beats Gearknob coating is VERY likely to fail around the 5 year mark ! Poor quality parts used i guess ?

[Mortis]

So I have replaced the reservoir cap with a new one yesterday. Topped up with water and took a round of 5-6km. The level had dropped a bit as usual. Could it be that the leakage is happening from elsewhere ? Im still doubtful due to the condensation on the neck and dry coolant marks on the reservoir. It could just be the level dropped due to expansion.
I have topped up again and will continue to observe it.
Still no signs of coolant leaking into the oil, no milkiness seen there.
What else can I check ?
Could it be the coolant reservoir itself ? Since it is technically an expansion chamber, it has a overflow/vent pipe that comes out near the cap, pointing downwards and on overfilling water it immediately comes out from this pipe. Im not sure how this overflow system works, but could it be the leak source ? It could explain the condensation and dried coolant along the beltline of the reservoir, but not the dried coolant drip stains on the opposite side of the bottle.
Should I just refill the coolant and add a bottle of radiator leak seal (LiquiMoly) and pray for the best.
Please help guys I would really like to try and figure out or narrow down this invisible leak before trying something major