mudgudgeon
Resident galah
Did you mix Toyota red coolant and standard green coolant?
The two react chemically and create sediment that looks like rust, and will coat hoses with crusty sediment and block heater and radiator cores
Mystery 1HZ overheating issue... please help. All cooling systems inspected, serviced or replaced and all seems fine! (1 Viewer)
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Did you mix Toyota red coolant and standard green coolant?
The two react chemically and create sediment that looks like rust, and will coat hoses with crusty sediment and block heater and radiator cores
- Thread starter
- #22
I only used that green /yellow coolant as far I am aware... but I did have some people do work on my car who may have without my knowledge. I will be careful just to use one going forward.
A few years ago I had a supposedly knowledgable Land Cruiser mechanic work on my truck that did just that; mixed the two coolants. Totally blocked up the radiator and caused all sorts of issues.
mudgudgeon
Resident galah
One extra thing to mention here: When I was refreshing my 1HDT, I had read that the oil cooler can get blocked up, especially if it was ever run with straight water (rust) or mixed green/red coolant (gunk). I pulled mine & replaced it just to be sure (and because I didn't know it's history) and mine had some moderate build-up.
Not saying that that's your problem, but just an additional thing for 1HZ/HDT people to keep in mind when they're having cooling issues.
Not saying that that's your problem, but just an additional thing for 1HZ/HDT people to keep in mind when they're having cooling issues.
- Thread starter
- #26
CLeaned out the gunk in the radiator... she is still overheating under load.
Going to run her without the thermostat, just to see what happens.
I will also look into this below.
Going to run her without the thermostat, just to see what happens.
I will also look into this below.
mudgudgeon
Resident galah
Bandaid on an arterial bleed.
If you take the thermostat out, put it in a tin and boil it. Check with thermometer or infrared heat gun to see what the water temperature is when it starts to open and when it fully opens.
My money is still on the engine fan clutch not being up to the task
Squash
SILVER Star
If your unit can maintain rpm on a climb or better yet increase then you are in the right gear. If you lose rpm or speed then you are in the wrong gear.
If you stop at the top of a hill to measure heat, then you will have to deal with heat soaking, this also happens once you stop a working engine. This is why I always allow my engines to cool down before shutting down.
Water boils at 100C
Coolant raises the boiling point.
A proper rad cap again increase the boiling point. Easy to search the about comment.
Furthermore: Check your overflow from the rad, if this is within acceptable limits and doesn't boil over or become empty then you are fine.
If you stop at the top of a hill to measure heat, then you will have to deal with heat soaking, this also happens once you stop a working engine. This is why I always allow my engines to cool down before shutting down.
Water boils at 100C
Coolant raises the boiling point.
A proper rad cap again increase the boiling point. Easy to search the about comment.
Furthermore: Check your overflow from the rad, if this is within acceptable limits and doesn't boil over or become empty then you are fine.
it would be a good idea to remove and clean the oil cooler to limit further contamination of your radiator.
please take a picture(s) when you do, curious to see your findings
the oil coolers are notorious for harboring LOTS of crud that you 100% want to address when replacing/boiling your radiator
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- Thread starter
- #30
Hi All, sorry been quiet on this front. I was up in Mozambique for a while.
I have driven about 8,000 km with no real issues... She does run hot on very hot days (38-40 degrees celcius) while on a sustained uphill or mountain pass.
Driving up Van Reenans pass I stopped about 90% of the way up and let her cool down as she reached 105deg C, and this was while running the heater. It was stinking hot, humid, and a seriously long uphill pass.
Driving back from Botswana to Johannesburg, also in 40 deg C heat, she climbed to about 103 degrees, and then I got stuck in bumper to bumper back ups, and driving slowly she cooled down nicely.
Driving down to Cape Town through the Karoo where the air is cooler, she never once went over 100. The only time she sneaked over was also driving up a mountain pass, Du Toits Kloof pass coming from Worcester into Cape Town. But she just got to maybe 101/102 deg C, so also totally within the 105 degrees threshold that I am judging as safe in my mind. But this was quite a short climb pass in comparison and not as hot a day, so definitely not ideal.
No issues climbing the long hills up the Groot Winterhoek mountains on a cooler day!
So clearly the cooling system is doing its job, but something is not perfect that it takes strain on long sustained uphills with fairly consistent higher revs (combined with hot weather).
@67azcruizr TBH I actually had to go look up where the oil cooler was. It seems the IP needs to be removed to access it. I completely ****ed up when re-installing my IP last time I removed it and had to send it to a diesel shop to fix, so I am a bit nervous to mess around with that as it seems my cooling issue is manageable (although not ideal). She is running beautifully and fairly stable, so I am feeling best not to mess with it, but if it becomes an issue again, then that is certainly the first thing I will look at. Thanks for your input, as I think this is only thing I have not checked in the entire cooling system.
- Thread starter
- #31
Top of the Groot Winterhoek mountains just outside Cape Town.
Did you ever perform a headgasket leakage test?
- Thread starter
- #33
yeah... thats why we replaced the head gasket.
Reflecting more on your question. I have not done one since replacing the head gasket.
during the HG replacement, was the cylinder head and block checked thoroughly?
