[docel]

Well....a lot of changes- hope it is not for the wrong reasons though!!
The Temperature gauge is just a rough indicator- the water temperature cannot go beyond the boiling point of 100degrees.
Unless it is in a pressured system, but even then 125 degrees is not possible.

If you have the wrong radiator cap too, water will try to 'spray' out of the radiator.

I think the problem is something else. Check out what Adheesh says.

Like i said: i hope the mechanic knows what hes doing!

[adheesh]

Originally Posted by Karthik1100

@docel, i changed the temperature union also. if i drive 100+kmph speed for about 15kms, temperature shows 125 deg., water spills or vapor comes out from radiator, sound of the engine changes. lacks performance. it was not parked for long time since i bought it. the previous owner parked it for 4-5months, it doest matter coz, i changed the head, valves, timing chain, cam sprocket, water pump, radiator to new. even air fuel mixture and dwell angle is also reset. i dont need to change the hose pipes as i have the very good quality one. and i made sure no leakage of water. fan belt is also stiff enough, no friction of brakes until we apply. before it was good when i went to goa and madikeri, now i cant drive my car more than 30kms without a stop.

The pressure caps seems to be fine. Please check the tappets and the block and revert back.

[Karthik1100]

@adheesh, thanks for your support, btw today only my mechanic set the tappets, but no use. but he has not checked the block completely. on the side of the block below the manifolds there are 2 dummy holes seems to be opened up. but he closed those things with m-seal or some waterproof adhesive. is that the problem?

[docel]

Hi Adheesh!

I have had this problem whenever I put in a new radiator cap. Had to stop several times till i removed the cap completely. I did a round trip from Bangalore-Chennai-Bangalore without the cap. No over-heating, Temp gauge showed normal.
Wonder why !

[adheesh]

Originally Posted by Karthik1100

@adheesh, thanks for your support, btw today only my mechanic set the tappets, but no use. but he has not checked the block completely. on the side of the block below the manifolds there are 2 dummy holes seems to be opened up. but he closed those things with m-seal or some waterproof adhesive. is that the problem?

The drain hole on the block is on the LHS (RHS when you face the car with the bonnet open) just next to the base of the distributor. Open it slowly and carefully with a 12mm spanner. If it breaks, (it does break easily) only a turner can help you. Please don't do/allow anyone to do anything irrational to the components like puting mseal in places it is not meant to be. These engines are very reliable and need only basic attention. Also, why were the above said components changed ?

Regards,
Adheesh Parelkar

[adheesh]

Originally Posted by docel

Hi Adheesh!

I have had this problem whenever I put in a new radiator cap. Had to stop several times till i removed the cap completely. I did a round trip from Bangalore-Chennai-Bangalore without the cap. No over-heating, Temp gauge showed normal.
Wonder why !

There may be two reasons for it (presuming that your radiator cap is original)
1. Padminis come with 7psi pressure caps while S1's have 9psi pressure caps. Interchanging them wont work.

2. The pressure cap retains 7/9psi of pressure in the cooling system to elevate waters boiling point. If a correct working pressure cap is used with either a weak or choked radiator or a chocked cylinder head or block, it will deteriorate the performance of the cooling system. One needs to check the integrity of the radiator as well as the hoses when fitting a new pressure cap. If either of them is weak, water leak would begin from there.

Regards,
Adheesh Parelkar

[docel]

These engine are very reliable and need only basic attention. Also, why were the above said components changed ?

Wanted to ask the same question myself. Never seen so many replacements for over-heating in my life.

[Karthik1100]

even i do the same thing if it is over heated. i just remove the cap fill the water and drive off.

no actually i wouldnt have change all, but i had reason to change them, changed the water pump coz it was making noise, change the head coz it was corroded, i wanted to change that from long time, and i thought it could be the problem and changed, and it is good to change the valves when head is changed. and radiator was also in bad state since i bought the car. even timing chain was also making noise. now smoothness and performance wise my car is much better than before, and also thought the heating issues will solve, i am sure, it was not because of the cap. even if the cap is removed still it gets heated up, advantage of the removal of cap is it gets cool soon.

[adheesh]

Originally Posted by Karthik1100

even i do the same thing if it is over heated. i just remove the cap fill the water and drive off.

Removing the cap is not uncommon. 99.9% of PP Taxis in Mumbai run perfectly well without a pressure cap. But that like covering a mess with a bedsheet. The problem needs to be attacked and not ran away from.

FYI these taxis also run without any oil filters or air filters.

[docel]

Thats what my friend told me to do years ago. I had to replace the cap with , I think , Matador or Amby cap as the PP cap was not available.

The other time the overheating happened was when the engine was clogged with muck. This was cleared by injecting high pressure water at the service station.

[Karthik1100]

now my main concentration is more on Block and timing chain setting as you told all mechanics cannot play with timing chain.

[docel]

I think you must change your mechanic. There are too many replacements now, mostly unwanted, as far as over-heating goes. So there are many variables now that must be eliminated one by one to get at the real problem. Maybe it'll all sort out somehow by trial and error, but it is always better to know what exactly was wrong and how it should be solved.

Nothing wrong in the replacements in the long run though.

[funkykar]

Does the older PP's come with thermostat valve? I had overheating issue with my NE. I had discusses with Ilango on this. He suspected a jammed thermo valve. I removed it for a while to see if it was the culprit. The heating issue is now gone.

[Karthik1100]

as per my mechanic said, thermostat valve is attached to the OEM water pumps, once it is removed, you wont be finding in any after market water pumps.

[ilangop]

Guys,
In one of the older posts Mr. Behram had mentioned that the OE thermostat valve of a M-800 will fit in our cars. The valve is not an integral part of the pump. It is just close to the pump.