back pressure

[connolly]

hi please can someone tell me what is causing the back pressure on a 300tdi is it head gasket

[Lacy]

You would need to expand a little on the problem......back pressure is a term usually reserved for exhaust systems where the system causes a restriction to gas flows and is required element of exhaust tuning.......

What problem is your car exhibiting

[Geobloke]

If the pressure is when you undo your oil filler cap then it is your cyclone breather unit on the side of the rocker cover! The sprung loaded valve sometimes sticks shut, so pressures increase in the engine. £25 to replace!

[connolly]

i was driving the disco when the temp started to go up so i stop turn of the engine found a hole in inlet pipe for heater and the water was coming out of that replaced pipe but i didnt know how to get the air lock out so i phone local garge they sent someone out and he said there was back pressure as the water was bubbleing in the header tank when the cap was off when he put cap back on you can hear the pressure building up

[connolly]

hi please can someone tell me what is causing the back pressure on a 300tdi is it head gasket
i was driving the disco and temp started to rise so i stop and turned the engine off once i got it back home on a lowloader i put some water in and the water was coming out of a hole in the inlet pipe for heater so i replaced it as i dont know how to get airlocks out of these i phoned someone up and when they came he said the water was bubbling in the header tank when the cap was off and when the cap was on you could hear the pressure building up

[Geobloke]

Ah so we are talking coolant. The coolant system is a pressurised system, which is why when you have been driving you must never ever ever take the rad cap or expansion tank cap off as the boiling water will explode out like a volcano!!!

Replace your holed pipe and you should be good to go.

[lynalldiscovery]

If its a 300 remove the thermostat plastic bung and with the header tank cap off ,top up the stat hole until the header tank level is correct, then refit header cap and continue to fill stat housing until full, refit stat bung and thats it!

If its a 200 just fill it up and drive it!

If it still gurgles after you have bled it you may have damaged the cyl head.



Lynall



Lynall

[connolly]

thank you for all your help