Hi all,

I have been reading on US based forums that 93 onwards 80's are blowing Head Gaskets left right and Centre with 100,000 miles on them (160,000k's)

Is this a problem with our Australian models too?

They are mostly blaming poor head gasket design due to asbestos being removed... and the fan clutches going etc. just wondered if it was happening over here too?

Apparently, Toyota's new Head Gaskets are metal and don't have the problem....

How many over hear have had HG's go on their petrol 4.5L 1fze engines 93 onwards?

BLOWN @ 342,000km
$2,800 later and all is well

Be good to your cooling system and it will be good to you.

Spend a few extra dollars on the coolant you buy, get the rad and block professionally cleaned and flushed every 2 yrs and most importantly.......
install a quality electrical water temp sensor, don't trust the OEM one, it's crap.

All this TLC is cheaper than a new head.

Mine has now done 240K, Radiator and block flush once every 5 years because I use a quality long life coolant. Never had a problem with the petrol engine temp gauge sensor.

Hey Brad, Just so you know - the OEM Factory temp gauge wont move until it is generaly to late from new. They are setup with a dead spot by toyota. That's why people are installing 3rd party temp gauge's - then if something iis on it's way out in the cooling system at leasl you can have some warning BEFORE it's too late and can have potential isssues resolved early.

You would be surprised how close to the line these run even with a new healthy system.

Also - just incase others dont know - the main cause for cooling systems to get gum'd up is mixing different coolants. If you change coolants - make sure you get a professional power flush of the whole system.

Thanks frank, my gauge generally is already on the move half a K down the road, maybe it has already been changed by the previous owner.

Hi,

I should explain what I mean....

The factory gauge will site in the middle and not move from 155 degrees F(70 degrees C) through to abou 230 degrees F(110 degrees C)

So once you notice it move a needle width above half way - your Head Gasket is likely gone and it is usualy too late to cool the engine down before warping a head.... As you know, if you turn off an engine that is hot - the temp will actualy go up!

By having a temp gauge(especialy on with a settable alarm) - you can take corrective action earlier and you can also do something to fix a potential problem if you notice iyour temps are sitting higher than usual on the freeway for example - an early indicator of a problem like a blockage etc.

From what I have been told the factory Toyota Red is able to work within this range and therefore doesn't boil and aerate.

If that is the case it shouldn't blow the head as there will be no hot spots to cause it to warp, so long as it heats evenly it should be fine. I ran the Toyota red in my 1FZ-FE and had no issue even with regular heavy towing. I know the gauge is slack but if everything is as it should be (coolant of correct type and radiator able to cope when thermo does open up) then it should function just as when it left the factory.

Cheers Glenn

I just bout sum tojo coolant. Need to flush my system. So will be draining it and givin it a flush,. God knows when it was done last. I have had the truck for a year and a half and havnt done it yet....

Hi Glenn,

My understanding(correct me if I am wrong - I am no cooling system expoert at all) is that it is not so much to do with what type of coolant - it is the pressure of 15PSI in the system with the coolant that raises the boiling point of the coolant - not the engine.

I believe the type of coolant has more to do ith anti-corrossive properties....

The amount of coolant affects freezing and boiling points of the coolant itself.

n relation to the gauge, what concerns me is that if there is a problem - ie small blockages slowing down coolant flow that you don't know about, with the gauge the way it is, it will overheat with little or no notice....

The thing that was concerning me in my original post is that in USA, people are clowing head gaskets left, right and centre - they are blaming the fact that Asbestos was removed from the gasket mterial and the design of the gasket itself - aparently, the new Toyota gaskets are all metal now and a different design around cilynder number 6 near the firewall where they are blowing the original ones.

So, I was curious if our Australian ones are any different to see if this is a common issue over here or not after 160,000 K's

Has anyone looked at the temp gauge mod thats posted up on I8Mud? Just wondering if the mod would work the same on the diesel factory temp gauge?

Hi Shane,

I have looked at it...

I belive it will be the same on a diesel.

I have been to Jaycar to locate the same resistors adn bit - they didn't have anything even close to the specs - so I haven't progressed any further...

Instead I decided it would be nice to have a seperate temp gauge that moves linearly as well as the factory one... This gauge's sensor is on the top radiator hose which is supposed to measure almost identical temps to where the factory one is according to guys who have compared temps from both locations.

I also got a digital one which has it's sensor installed on the thermostat.

Hi Frank,

You are correct but it is a combination of all of these factors, pressure raises the boiling point (generally 9 PSI is common) but also the coolant itself chemically changes the (distilled) water and further raises its boiling (and lowers freezing) points. the coolant chem is designed to modify the water itself not perform any function on its own accord (with respect to cooling). The amount of coolant doesn't do much so long as you meet the min spec per volume of water, for most it is about 33 percent and as high as 50 but anything past that can hinder performance because it is the water that it modifies and without the correct ratio it can't work properly.

I know what you mean about the gauge, it is a concern, however I do wonder if it would even show as if you have a blockage it will still boil at that point and therefore aerate and warp the heads and yet without coolant flow past the blockage the gauge will be none the wiser to it even if it could show it.

Perhaps regular flushes and fresh coolant aren't part of the yanks maintenance schedule, I have been on Ih8mud and slee for a good while and none of those guys really look after those cars, in fact they would have to be some of the worst kept cruisers I have ever seen, wheel bearings seizing are common issues raised and suspension components often have to be taken to with a gas axe to be removed. I strongly suspect that it is a attitude difference that has them doing the head gaskets.

In my time owning the 1FZ-FE no one (including a close mate who owned a toyota dealer ship and did all of his time with them) raised any issues with heads on the 1FZ-FE. He's anal to I was doing all sorts of wierd stuff to it but he never mentioned the heads as an issue.

Cheers Glenn

I am very glad to hear this Glenn, it's been concerning me some what.

Thanks for making the time to respond

PS Happy new year!

I had some significant cooling issues with a previous Toyota diesle engine. After consulting several radiator shops the advice was the same from all.

The truck will not overheat until the water temp has hit 115 deg C assuming a good coolant, good rad cap and good seals.

The most alarming thing was that they all confirmed the toyota OEM gauge will not move until the temp hits the 115 Deg C. This was done by Totota to prevent the less technically mined worrying about their temp gauge constantly rising and falling and not understanding that this is a normal function when the engine is on and off load.
To counter this Toyota and most other vehcile manufacturers put in a null point so that the gauge stayed constant 'till the coolent temp got too hot.

Problem with this is that when the temp hits 115 Deg C and the gauge starts moving most will assume everything is OK untill the gauge hits the red zone, by then the coolent temp could be 125 Dec +. There goes the head gasket at best, the head at worst.

I guess as long as you know the facts and you stop whenever the gauge moves a milimerer above its normal position then life is sweet. If you don't have a calibrated eye ball, or someone else often drives your car and is oblivious to the other gauges other than the speedo then you probably want to install a quality elecric water temp gauge in the truck. The gauge is cheaper then getting the head gasket replaced and a lot cheaper then getting the head replaced.

Finally, this is not just for the petrol heads, you dieselers should also invest in the gauge.