zd30 y61 continuous bubble in reservoir

[seekers282]

hello guys,my 01 nissan patrol y61 with zd30 engine have continuos bubble in reservoir tank,my coolant in expansion tank look like it being suck in to the radiator but my reservoir overflow tank was overfull due to excessive pressure being push from my coolant system..could it be a cracked head?ive just top overhaul my engine..could it be my head gasket?or any other internal cracked or leak?anyone experience it before?

[BigRAWesty]

Unfortunately you do have a leak..
Does it increase with rpm (you'll have to rev up and hold to check this) or engine temp?

[Parksy]

Replace your radiator cap first before looking at the more expensive options...

[Wine_maker]

In bad case its crack in the head of cylinders or head of cylinders gaskets.

[seekers282]

Unfortunately you do have a leak..
Does it increase with rpm (you'll have to rev up and hold to check this) or engine temp?

engine temp is not overheating..it still stays on normal range..

[seekers282]

Replace your radiator cap first before looking at the more expensive options...

radiator cap is brand new..just got it replace 2 days ago..

[seekers282]

In bad case its crack in the head of cylinders or head of cylinders gaskets.

if it does..anyone have tried using k-seal product that seal any leakage from inside?im thinking on using that as my last alternative..if still doesnt fix it..then im gonna try to look for a swap,td42 perhaps..

[happygu]

Seekers,

Did you get the head crack tested whilst you had it apart?

Mic

[seekers282]

if it does..anyone have tried using k-seal product that seal any leakage from inside?im thinking on using that as my last alternative..if still doesnt fix it..then im gonna try to look for a swap,td42 perhaps..

sadly i didnt..just checked it by seeing it with eyes..since we check the head gasket has symtom of blown sign..so i thought the head was fine and its just a blown head gasket..its was ok for two days after the top overhaul..after the next day..there it goes again..bubble on my overflow tank..if the head was cracked..it should have bubble on the 1st day right?

[Rickie3]

Did you check the head for warp with a straight edge when you had it off?, If your going to such extremes removing a cylinder head its always worthwhile sending it in to be preasure and crack tested and to make sure its not warped, i'm a petrol mechanic and have also replaced a few cylinder heads on diesel engines and I find the biggest mistake mistake people make when replacing heads is filling the radiators with coolant, i'm old school I use straight water after installing a cylinder head, drive the car for 500 k's then drain and fill up with coolant, this procedure allows the glues in the head gasket to seat and seal properly, some coolants destroy new head gaskets