Bubbling sound from dash when accerating

[oldtimer40]

Hi Guys,

I have a Nissan Patrol GQ TB42E on Petrol / LPG, and had the truck for 3 months now, fixing all the problems as the previous owners just let it go.

All has been well, but for the last 2 weeks or so. I have been noticing a bubbling gurgling sound coming from the dash when accelerating (Oh Ohhh!!! - I had a car in NZ that was doing the same thing, and it turned out to be the head gasket on the way out, leaking compression into the cooling system - very expensive to fix.)

I have been reading on here, and have noticed others experiencing the coolant level dropping in the radiator, and when I get home after a long drive the overflow bottle is bubbling away. In the morning the overflow tank level is 1" over the MAX mark!!!

Another post on here suggest's that air could be getting in from through the hose from the radiator to the overflow tank, and the hose inside the overflow tank, this could explain how air is entering the system. These hoses have not been changed, but after reading the post they will be changed.

So far I have done: New Radiator, New radiator cap from Patrol Apart, All new hoses including heater hoses, etc. The head has been done by ALL HEAD SERVICES who have put extra hoses & plumbing to protect the head from overheating, done some time ago before I got it, all these hoses have been changed also.

No coolant leaks, Engine Oil is good, No oil in the coolant. Just that the coolant is getting low and ending up in the overflow tank. I have tried running the A/C on maximum heat and full fan to help purge air from the system. This gets rid of the bubbling for a little while.

I am hoping the bubling sound when accelerating is only this air from the overflow bottle, and am praying it is not a leaky head gasket or cracked head, I will try changing the hoses as above.

In the meantime, any other things I can try?

[Stumpjumper]

Thats not sounding good oldtimer. when you increase combustion chamber pressure by opening the throttle and accelerating, well that pressure is finding a path to the cooling system. This then increases the pressure in the cooling system only finding relief by opening the rad cap and running to the overflow bottle.
Do a pressure check with plugs out, probably find one cylinder is down. I am thinking head gasket or crack. Sorry

[Stumpjumper]

ALL HEAD SERVICES If you can find a recept....... check the warranty..............just a thought

Marty

[Stumpjumper]

Another test that can be done, I remember Timbar and Tony mentioning it a TK test is a good place to start as this checks for exhaust gasses in the cooling system.

[pearcey]

As suggested first get a KT test. The bubbling sound is more than likely the coolant circulating through the heater.Also check that there is not air trapped in the cooling system seeing that the pipe work is not std. On a lot of late model vehicles they have a bleed screw either at the front or the back to bleed off any trapped air due to pipe work being higher than the top of the head or rad.

[ishie]

Hi Guys,

I have a Nissan Patrol GQ TB42E on Petrol / LPG, and had the truck for 3 months now, fixing all the problems as the previous owners just let it go.

All has been well, but for the last 2 weeks or so. I have been noticing a bubbling gurgling sound coming from the dash caps (http://www.jcwhitney.com/dash-caps/c13273j1s17.jcwx) when accelerating (Oh Ohhh!!! - I had a car in NZ that was doing the same thing, and it turned out to be the head gasket on the way out, leaking compression into the cooling system - very expensive to fix.)

I have been reading on here, and have noticed others experiencing the coolant level dropping in the radiator, and when I get home after a long drive the overflow bottle is bubbling away. In the morning the overflow tank level is 1" over the MAX mark!!!

Another post on here suggest's that air could be getting in from through the hose from the radiator to the overflow tank, and the hose inside the overflow tank, this could explain how air is entering the system. These hoses have not been changed, but after reading the post they will be changed.

So far I have done: New Radiator, New radiator cap from Patrol Apart, All new hoses including heater hoses, etc. The head has been done by ALL HEAD SERVICES who have put extra hoses & plumbing to protect the head from overheating, done some time ago before I got it, all these hoses have been changed also.

No coolant leaks, Engine Oil is good, No oil in the coolant. Just that the coolant is getting low and ending up in the overflow tank. I have tried running the A/C on maximum heat and full fan to help purge air from the system. This gets rid of the bubbling for a little while.

I am hoping the bubling sound when accelerating is only this air from the overflow bottle, and am praying it is not a leaky head gasket or cracked head, I will try changing the hoses as above.

In the meantime, any other things I can try?

had the same problem on my dash.. i have also GQ TB42E and its freaking hard to fix the problem. can you help me on this? im sure yours is already solve now.

[jempot]

I have the same sound but the coolant level between radiator and overflow is fine and no oil mixing with coolant and vice versa. I will try getting rid of air from the cooling system.
Interested to know the outcome of the others. What is a tk test?