Coolant Problem?

[MOZ]

Hi Guys - (Landcruiser Colorado - 1999) I'm really looking for some good advice from you experts, the thread might be somewhat long (sorry) but I need to give you the full story.
For sometime I have been losing coolant, sometimes nothing other times quite a bit, I must also state I mainly use the Landcruiser for towing my large twin wheel caravan.
So recently, apart from changing the complete brakes & discs all round, I decided to change the Radiator and top & bottom hoses (all new) as I thought I might be losing coolant, I could never see it and there is none in the Oil.
So this has all been done, I went to take it out last week with the caravan on the back and it 'boiled' over, blew the expansion tank cap off and it was like a steam pipe, the radiator, top & bottom hoses were very hot also. (only done 10 miles)
When I had the new Rad fitted and was running it around without the caravan I was still losing some coolant, so I was advised to put some 'steel seal' in the rad, which I did.
I have now used the Landcruiser on a couple of occasions (without the caravan) not used any coolant, do not appear to see any water leakage anywhere, rad and hoses very hot (20 mile trip)
Temp Gauge - when it boiled over it went right up, but at present it is doing what it has always done, within approx 2 miles it goes up to just below halfway, after 20 miles, still in the same position. So I'm now looking for some good sound advice, anyone have any without seeing the cruiser?
Thanks.

 

[Shayne]

I guess being a 1999 truck this is a 1kz-te engine ?

Just so you are aware these trucks do have something of a reputation for blown heads but lets just hope that's not your problem .

Should have changed the thermostat when you did the radiator .

I had a leak i could not find and began to suspect i had cracked the head but it turned out to be the heater pipes were dripping coolant onto the turbo which of course instantly evaporated the evidence .

 

[Beau]

Sounds as though either the head gasket has failed, or worse off, a cracked head.

Best bet is to get the coolant system pressure tested, but with what you've described it sounds as though compression is entering the coolant system for sure.

 

[MOZ]

Hi Guys - my first and worst reaction was either head gasket or head, but I have spoken to several mechanics and they all seem to come up with different ideas, i.e. one did mention the thermostat, whilst another dismissed this and said it was working, he mentioned he had a similar fault with a car, did all the head and found out it was the water pump? Hence the reason on coming to the experts.

 

[Shayne]

Hi Moz your first post history somewhat confuses the issue to clarify would i be right in thinking -

It no longer leaks ?
The temp gauge remains in normal range ?

And your current concern is the rad and hoses get hot after 20 miles ?

 

[MOZ]

Hi Shayne - it's all confusing?
When it boiled over the cruiser is in the same state as now (after new rad, hoses and steel seal) at this point still losing some water.
I've run it on the drive to look for water, run it out in the road and have only lost an egg cup full.
The temp gauge has always (3 years) shot to just below halfway after approx: 2 miles and is still doing it now.
It appears the rad and hoses are now getting much hotter than previous.
I have a thermostat so I think it might be worth changing as these can play up from time to time. Then I can try it again, but at present I am not trying under load, i.e. 2 ton caravan.

 

[Shayne]

A failed rad cap would cause leaks and pop the cap on the expansion tank . Where did you get the rad from ?

 

[MOZ]

Hi Shayne - I had the rad from a guy who supplies rads to my lad who works for a car spares place in Oldham, it was the correct one for my Cruiser because I checked it on the manufacturers web site, I do not have the information at present but if I remember it was manufactured by a German Company. The rad cap was not a good fit at all and I'm having another one delivered to me tomorrow, supplied by the same guy as the rad.

 

[Shayne]

Great cheapest simplest things first

Stat next , if its stuck open the rad gets no chance to do its job . You can get a towing stat which opens at a lower temp search the forum for the part number .

 

[BobMurphy]

You can get a towing stat which opens at a lower temp search the forum for the part number .

A 76 degree 'stat may solve your problem when towing:

 

[froggy Steve]

I have a 76 degree stat, extra cooling rad for the gear box, (and a new rad) and fitted an aftermarket digital temp reader to show just how hot the water running round is - the genuine temp guage is a waste of space. I am somewhat scared of boiling her up!

 

[AndyCook]

Also check that the fan is doing its job, can you hear it roar when engine is hot ?
the fluid in the viscous coupling can degrade over time and mean the fan doesn't lock when hot, meaning it doesn't cool the rad properly

 

[froggy Steve]

Oh yes - filled my fan coupling with heavier oil so it runs practically full time....too much i think

 

[AndyCook]

Oh yes - filled my fan coupling with heavier oil so it runs practically full time....too much i think

I did that with the Toyota 4Runner I owned about 7 years ago, and found it also sapped the power slightly and used more fuel. So I drained some out again to stop it being on all time.

 

[Shayne]

60ml

 

[diggerdave]

I don't know how much the 'stat that Bob has posted above costs from Toyota. However, if it's really pricey or hard to get, this is the 76-degree thermostat I fitted http://www.yoyopart.com/oem/138783/herthbussjakoparts-j1532020.html
Google the name/part number and there are lots of buying options. I think I got mine via Amazon for around £24.

 

[MOZ]

I don't know how much the 'stat that Bob has posted above costs from Toyota. However, if it's really pricey or hard to get, this is the 76-degree thermostat I fitted http://www.yoyopart.com/oem/138783/herthbussjakoparts-j1532020.html
Google the name/part number and there are lots of buying options. I think I got mine via Amazon for around £24.

Hi guys - Thanks for your input, I've just managed to order a new 76 deg. Blue Print Stat, will be with me tomorrow.
So tonight it's back to trying to take the stat housing off, what a job, who designed this, I've managed to take off bottom Stone Guard, disconnected bottom hose, now stat housing is halfway up the engine and have to try to work at it from above, trying to get hand down to undo the two bolts, I've managed to get the top one out, now trying the bottom one, not alot of room, will move filter ducting tonight to see if it gives me more room.

 

[MOZ]

Hi guys - Thanks for your input, I've just managed to order a new 76 deg. Blue Print Stat, will be with me tomorrow.
So tonight it's back to trying to take the stat housing off, what a job, who designed this, I've managed to take off bottom Stone Guard, disconnected bottom hose, now stat housing is halfway up the engine and have to try to work at it from above, trying to get hand down to undo the two bolts, I've managed to get the top one out, now trying the bottom one, not alot of room, will move filter ducting tonight to see if it gives me more room.

 

[MOZ]

Just an update.
Have ordered and will pick up new Stat today, finally managed last night to get the housing off (not much room) and old stat out. So from tonight, I will start to put it all back and we will see what happens.
Next question. Refill coolant system, several say put only Toyota Red Anti Freeze in the system, I have always used Red anyway but I get this from an oil company around the corner, Caldo Oils (own make) what do you guys think? Once again thanks for all your help.

 

[Shayne]

I think most of us use Toyota's own for its corrosion prevention properties but its probably not much different from the rest so its personal choice . Toyota red for me .