Vn series 1 V6 over heating issue (Please Help)

[M3ZZA]

I have a problem with my series 1 vn motor.

I just replaced the lower radiator hose since mine was split i replaced it today and then i topped up the radiator all the way and set the heater to full power and on hot with the setting set to the floor. I then turned the car over with the radiator cap off and let it idle until all bubbles came out off the radiator.

I then put the cap back on but within 7-10min it hit half way and the thermos won't doing s**t and the temp warning light kept on beeping.

I then let it cool down and started it 30min later and within 3 min the temp light warning came back on when it sat at a qaurter and the thermos kicked in but nothing was happening.

I turned it off and i noticed that there was a weird small hissing like noise near the coil pack and the lower radiator hose was cold near the radiator but very hot near the water pump. Also the main hose at the drivers side off the radiator was making a weird noise inside it like there was a pressure build up and like it was full off air bubbles.

Whats wrong with my motor did i pop a head or something ?

 

[wortus]

Is it an early motor with a surge tank or the later with the radiator cap as what you commonly refer to as a "series 1" has the thermostat at the back and a surge tank with a pressure cap on that, there is no radiator cap.
You may have air in the system, if it is the early motor with a surge tank check to see if the small metal pipes that come out of the inlet manifold are blocked as these tend to let the air out of the top of the motor. If it has the thermostat at the front there is an air bleed on the cover undo it and see if any air comes out.

 

[M3ZZA]

its a 1991 vn calais which used to have a series 2 motor in it. It now has a series 1 motor with the thermostat behind the motor but it still has a series 2 radiator and overflow setup ?

 

[wortus]

its a 1991 vn calais which used to have a series 2 motor in it. It now has a series 1 motor with the thermostat behind the motor but it still has a series 2 radiator and overflow setup ?

Did you fit the surge tank? I think you'd be better off getting a series 1 radiator and surge tank and connecting it up as recommended. Sounds like you might have air trapped in the system.

 

[M3ZZA]

I wouldn't have a clue mate since my mate did the conversion while he owned the car.

 

[M3ZZA]

what does the surge tank look like ?

 

[wortus]

what does the surge tank look like ?

It's a plastic bottle that sits where the overflow would have been on your Calais with it's original motor. It has a pressure cap that screws down. It has 3 hoses coming out of it.

 

[M3ZZA]

That's what the engine bay looks like now.

 

[Immortality]

sounds like it hasn't been bleed properly. the other question is whether the thermostat was installed correctly?

to bleed it properly, you need to run the engine with the radiator cap off, fill the radiator, run the engine, heater on full hot etc. as the engine temp rises and the thermostat opens the coolant level in the radiator will suddenly drop. keep topping the radiator until full.

the s1 motors were self bleeding into the pressurised reservoir (most people say the system is crap, however they use this design on late model engines ) from the pics i can't see what has been done with this connection. it is a black hose with a red stripe on it at the front of the intake manifold. maybe loosen off the hose clamp to let the air out of the coolant system.

 

[88GreenVN]

If your getting the warning temp light going off then there is not enough coolant to cover the sensor at the back of the manifold.

I'm about to re fit a S1 radiator to the 88 wagon as it keeps using coolant and the S2 radiator was diagnosed as the problem. It looks like the cap cant take the pressure with the closed S1 system used and lets the coolant go over a few weeks setting off the warning lamp.