[Rehaan]

Scooby05,

Heres my guess :

Something is restricting the flow of coolant through the cooling system.

Therefore, at idle and slow speeds, its managing to mantain the temperature okay - but at higher load & speeds the cooling system can't keep up with the additional heat produced.

Possible points where this restriction in flow could be :
1) Thermostat not opening all the way as it should
2) Kink / bend in one of the pipes to/from the radiator
3) Weak water pump


My bet / hope would be point #1 - thermostat. Its easy to check and easy/cheap to replace too.

cya
R

EDIT - You might also wanna check that the connections are solid on all relays/cut-offs for the fans. Those could possibly be shaking loose at speeds? Though your problem doesn't sound erratic in any way, so its a long shot...

[Jaggu]

Originally Posted by scooby05

Boss, As the car doesnt Heat in slow traffic with AC on, how does the size of compressor matter, though we have a sanden 507 on her fitted by millenium motors, the pune maruti dealers.

Boss, it does matter. You put a large compressor on that engine and it will overheat! due to the greater load. Why do you think manufacturer always keep the compressor at conservative specs?!

But i guess thats not the case here, though 507 is slightly heavy duty stuff. I prefer 505's but then if you are cooling the whole cabin it might not be adequate.

Your problem is to do with coolant circulation \ air circulation at the radiator:

1) It can be a bad thermostat - Chances are less since vehicle is new. I dont recommend removing it, since it kills the overall feel good factor, especially while starting up and initial driving, when cold.

2) The coolant cap is acting up, creating a vacuum lock in the system. Check coolant tank for any overflow signs. I remember another Pune member posting issue with coolant tank on his new Gypsy.

3) The radiator is not able to cope up with the AC. No other way out then, apart from moving the ac grill from front to under the car (if you offroad, you are toast!). Or go for a bigger / better radiator so you have more buffer.

How is the AUX fan, is it powerful enough and good enough for the size of the AC grill? Hopefully its mounted right on the AC grill and has proper shrouds?

One last question how is the spacing between both the grills? Is it possible for you to post a picture of the setup? Both from the front and the rear (engine bay side).

[Blue Thunder]

Originally Posted by scooby05

...My question remains, what could be causing the extra load on engine in higher RPM that causes the heating?

Are you running the stock radiator? If yes, then the point 3 in Jaggu's post above is the answer.

The stock Gypsy radiator, with A/C condenser in front, is known to cause engine overheating, since it's cooling capacity is affected by the a/c condenser in front of it. So, you either move the a/c condenser to a different location or get a radiator of higher cooling capacity.

Originally Posted by Jaggu

...

3) The radiator is not able to cope up with the AC. No other way out then, apart from moving the ac grill from front to under the car (if you offroad, you are toast!). Or go for a bigger / better radiator so you have more buffer.

...

[suzuki san]

Hi,

I faced a similar problem in my Gypsy King a few years ago.
I changed the radiator to a large copper core one made specially by Lawrence Radiators for me. It made no difference whatsoever.
I tried removing the thermostat. Still no success.
No one from Maruti or other well reputed A/C firms in Bombay were able to solve the problem.
The only thing which should work is a high powered electric fan in front of the condensor - I found out later that these are available.

I finally sold the King as I got tired of this problem.

Regards,

SS

[GTO]

Scooby, I had the EXACT same problem in my Jeep. When driving in the city, offroading, or any other activity at low speeds (including idling for 2 hours), there was absolutely NO overheating. However, the only time that it did overheat is when cruising at 80 - 90 kph. The minute I used to slow down (say to 60 kph), the temp needle would fall back in place.

Reason: Your radiator is entirely blocked out by the air-con condensor. At high speed, the air flow is entirely messed up too. You will notice this happening, irrespective of whether the aircon is switched on or off.

Solutions:

- Get an XXL size radiator with a more powerful fan.

- Give the radiator direct access to frontal air flow. Move the air-con condensor as per GoSlow's recommendation. I haven't personally seen any Gypsy with such a setup, but where else can it be moved?

This will require a certain amount of trial & error, as most significant modifications do. You are in luck because your Gypsy is in warranty & the air-con is dealer installed. Pass the headache on to them and REFUSE to take delivery until they sort the matter out. It's entirely their responsibility to make it work. Write an email to Maruti (from their website). You will be surprised with the quick response.

[SPIKE ARRESTOR]

i agree to the radiator size and powerful fan setup, but since the condenser is blocking air flow to the radiator, this phenomena of overheating should happen at low speeds also, in my opinion as vehicle speed increases "ram air effect" also increases, thereby providing air draft. Please correct me if i am wrong.

Spike

[ex670c]

Originally Posted by SPIKE ARRESTOR

i agree to the radiator size and powerful fan setup, but since the condenser is blocking air flow to the radiator, this phenomena of overheating should happen at low speeds also, in my opinion as vehicle speed increases "ram air effect" also increases, thereby providing air draft. Please correct me if i am wrong.

Spike

Hi Spike,

Are you saying that at higher speeds more air flows through the radiator at obviously higher speeds and escapes through the gaps in the Radiator & Radiator Grille, thereby reducing the cooling effect.

We have seen this problem in A/C fitted Armadas/MM540s.

Regards,

Arka

[scooby05]

Originally Posted by GTO

Scooby, I had the EXACT same problem in my Jeep. When driving in the city, offroading, or any other activity at low speeds (including idling for 2 hours), there was absolutely NO overheating. However, the only time that it did overheat is when cruising at 80 - 90 kph. The minute I used to slow down (say to 60 kph), the temp needle would fall back in place.

Reason: Your radiator is entirely blocked out by the air-con condensor. At high speed, the air flow is entirely messed up too. You will notice this happening, irrespective of whether the aircon is switched on or off.

Solutions:

- Get an XXL size radiator with a more powerful fan.
- Give the radiator direct access to frontal air flow. Move the air-con condensor as per GoSlow's recommendation. I haven't personally seen any Gypsy with such a setup, but where else can it be moved?
.

This will require a certain amount of trial & error, as most significant modifications do. You are in luck because your Gypsy is in warranty & the air-con is dealer installed. Pass the headache on to them and REFUSE to take delivery until they sort the matter out. It's entirely their responsibility to make it work. Write an email to Maruti (from their website). You will be surprised with the quick response.

Its very strange, for the first time in my 40 years have I experienced a car heating at high speed[80kmph], though this is only when AC is on. The aux Fan has been replaced and works Very well and in the right direction, i.e. sucking in air thru the grill!

When I switch off the AC the temperature goes back to normal in 5 minutes! I am suspecting either a short cycling of the airflow by one of the 2 fans or need for a bigger radiator, but will first change oil-mobil, check caps, fill the gap between radiator and front cowl with thick foam.

My red gypsy '99 with an original radiator with AC does not heat!

I dont think this is feasible. Since the car is to be used at Khandala mainly, i guess need of AC is limited anyways, so why make such alterations


They will ask me to send the car over to Pune-millenium, and I will not be able to monitor, Maybe I can request them to get the problem checked at Sai Mumbai, where I know the owners.

[starter]

Originally Posted by Jaggu

apart from moving the ac grill from front to under the car (if you offroad, you are toast!). Or go for a bigger / better radiator so you have more buffer.

Hey Jaggu,
Why can't we just move the condensor under the car?
Do you mean that this would get hit during serious off-roading?
Can't we conceal this somewhere near the rear-differential such that the probability of it getting hit is reduced?
How expensive and how difficult is it to put a bigger 3-core radiator into the gypsy? Would it need some modifications on the chassis to accommodate this?
Thanks a lot.
Warm Regards,
Deepak

[SPIKE ARRESTOR]

Originally Posted by ex670c

Hi Spike,

Are you saying that at higher speeds more air flows through the radiator at obviously higher speeds and escapes through the gaps in the Radiator & Radiator Grille, thereby reducing the cooling effect.

We have seen this problem in A/C fitted Armadas/MM540s.

Regards,

Arka

Hi Arka,

The air flow also depends on the type of deflector used:- Parallel flow or Cross flow. Does Gypsy have two types? What type of deflector does it have?

Spike

[ex670c]

Originally Posted by SPIKE ARRESTOR

Hi Arka,

The air flow also depends on the type of deflector used:- Parallel flow or Cross flow. Does Gypsy have two types? What type of deflector does it have?

Hi Spike,

My guess the Deflector is the Shape of the Radiator Grille leading to the Radiator.

Please educate us on the following.

1) Ram Air Effect (Cooling/Radiators)
2) Cross Draft
3) Parallel Flow Deflector
4) Cross Flow Deflector

Regards,

Arka

PS - With Diagrams and equations

[SPIKE ARRESTOR]

My question in the earlier post still remains unanswered, what kind of deflectors were used on AC fitted Armadas and MM540s?

Spike

[ex670c]

Originally Posted by SPIKE ARRESTOR

My question in the earlier post still remains unanswered, what kind of deflectors were used on AC fitted Armadas and MM540s?

I don't know,What is a Deflector and Where is it fitted?

[Jaggu]

Originally Posted by scooby05

Its very strange, for the first time in my 40 years have I experienced a car heating at high speed[80kmph], though this is only when AC is on. The aux Fan has been replaced and works Very well and in the right direction, i.e. sucking in air thru the grill!

I think we have a lead from Spike, check the grill configuration of the ac grill it should match the design of the radiator fin. Also as you mentioned the sealing should be good so that air doesn't leak.

Engine oil might/will not really help, i suggest you solve the heating issue before shifting to Mobil.

Originally Posted by starter

Hey Jaggu,
Why can't we just move the condensor under the car?
Do you mean that this would get hit during serious off-roading?
Can't we conceal this somewhere near the rear-differential such that the probability of it getting hit is reduced?
How expensive and how difficult is it to put a bigger 3-core radiator into the gypsy? Would it need some modifications on the chassis to accommodate this?
Thanks a lot.
Warm Regards,
Deepak

You can move it anywhere, but to keep the efficiency and the tubing to be minimum, usually its mounted somewhere close to the front passenger area in such set ups. This becomes a problem while crossing ramps.

Bigger radiator - Dont know the cost, but yes one has to custom build the radiator.

Originally Posted by SPIKE ARRESTOR

Hi Arka,

The air flow also depends on the type of deflector used:- Parallel flow or Cross flow. Does Gypsy have two types? What type of deflector does it have?

Spike

Something which rang a bell for me and which might be the problem in this case.

Scooby some detailed pic of the grills would definitely help, Spike can identify the design for us also i guess.

External deflectors are not there in gypsy if i remember correct, been a while

[SPIKE ARRESTOR]

Originally Posted by ex670c

I don't know,What is a Deflector and Where is it fitted?

Buhahahaha, so finally our Dear Arka has agreed that he doesn't know something. Let me try and explain, there are two types of deflectors (placed right behind the front grille on which the bonnet stay rod is mounted) parallel flow and cross flow deflectors, parallel flow have both the vertical plates parallel to one another, on projecting them towards the car centre line they never meet, whereas the cross flow are inclined towards each other, on projecting them towards the car centre line they meet at a point, both these along with the radiator shroud determine how the air is directed (Draft), if the deflector (along with shroud) is mounted according to the Radiator design there is very less possibility that air may escape no matter at what speeds, The very reason for using deflector with shrouds is to "direct the air" to its destination aka Radiator. Hope this clarifies

@Jaggu bhai smart boy you are

Spike

P.S.- If anyone in the forum could post a few pictures from the engine bay (Gypsy/MM/CJ) that would help and clarify things in a better way.