Head gasket

[GSMNP125]

Will a leak in the head gasket keep the radiator from drawing fluid from the over flow tank?
The engine doesn't get hot but when I look in the radiator tank all I see is the metal first rung of layor of metal and it's not covered by any antifreeze. I'm replacing the filler hose but don't think there is a leak there.

Help

Thanks

1986 4-Runner, 4 spd trans, 280 K

 

[fishrod]

Will a leak in the head gasket keep the radiator from drawing fluid from the over flow tank?
The engine doesn't get hot but when I look in the radiator tank all I see is the metal first rung of layor of metal and it's not covered by any antifreeze. I'm replacing the filler hose but don't think there is a leak there.

Help

Thanks

1986 4-Runner, 4 spd trans, 280 K

Thats an excellent question and without any physical proof to back up my answer, I would have to say YES!!!

My overflow tank would stay full even when my Rad would go down before I blew the head gasket. Now that its fixed my radiator now draws fluid from the overflow tank when it needs to. Much easier to top up the overflow when the engine is hot than it is the radiator (when on long trips for example)

Are you losing much coolant and/or oil? Before the HG went, I couldnt find any visible coolant leaks and would lose about 1 litre of coolant and half a litre of oil on a long trip (say 800kms)

After the head gasket was fixed I have never had to top up oil between changes and barely ever have to top up the coolant either!!

 

[KidVermicious]

Stand to reason - your overflow fills as the engine heats and the fluids expand, then empties as they cool down. If there's damage to the head gasket, coolant will go there as well as/instead of the overflow bucket when it heats up, and it'll suck air/oil there when it cools down instead of/as well as sucking radiator juice from the overflow.

If you think your head gasket is blown, look for oil in your coolant and coolant in your oil. Lack of same does not rule out a bad gasket, but presence of same is a sure sign.

 

[fishrod]

If you think your head gasket is blown, look for oil in your coolant and coolant in your oil. Lack of same does not rule out a bad gasket, but presence of same is a sure sign.

I never saw oil in the coolant or vice versa. Even when the gasket blew fully and clouds of white smoke were pouring out the exhaust the oil was still clean. There was a tiny tiny bit of white stuff on the inside of oil cap, but not much at all. This was after I had to drive it a couple more times after it fully blew. Up onto a trailer and then down again and into a shop to get fixed etc.

I am not convinced that the "white stuff in the oil" is such a good sign. But thats just from my 1 expereince. 8)

 

[KidVermicious]

I never saw oil in the coolant or vice versa. Even when the gasket blew fully and clouds of white smoke were pouring out the exhaust the oil was still clean. There was a tiny tiny bit of white stuff on the inside of oil cap, but not much at all. This was after I had to drive it a couple more times after it fully blew. Up onto a trailer and then down again and into a shop to get fixed etc.

I am not convinced that the "white stuff in the oil" is such a good sign. But thats just from my 1 expereince. 8)

That's what I'm saying - lack of oil/coolant mixing does not rule out a bad gasket. But if you do have coolant in your oil/oil in your coolant, then you almost certainly have either 1) a blown head gasket, or 2) somebody who can't tell the difference between a radiator and a 710 cap.

 

[fourwd1]

... But if you do have coolant in your oil/oil in your coolant, then you almost certainly have either 1) a blown head gasket, or 2) somebody who can't tell the difference between a radiator and a 710 cap.

A hole worn thru the Timing Chain cover by a loose TC is a common cause of oil and coolant mixing.

 

[KidVermicious]

A hole worn thru the Timing Chain cover by a loose TC is a common cause of oil and coolant mixing.

Woops, you're right.

Either way, it's bad.