I recently installed a 2lte engine on a Fj40 and regularly flush the radiator , i dont seem to find the rust to run out. The engine is second hand and was recently brought to life about a year ago . Is this normal?
Murky radiator water (1 Viewer)
- Thread starter Bernard9102
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GTSSportCoupe
2LTE abuser
Usually when the heads crack in Japan they just keep topping them up with straight tap water. This causes the iron block/head to rust in the coolant passages. There is a chance your motor still has head problems, so be careful. The other problem is when they keep adding tap water it also keeps entering the cylinder bores when the truck sits (through the cracks) and can rust/damage/pit the bores. I've seen a few like this now. Hope yours has none of these issues though.
I would certainly say it's not normal on an engine that has been well maintained but sadly they're often neglected. Some people confuse "reliable engine" with "needs no maintainence". Are you getting flakes or rust or just rust coloured coolant?
I've had success curing the rust coloured coolant problem by repeatedly filling the engine with water, firing it up for say 20 seconds and dumping it until it goes clear. Then following that up with 1ish hour drive with an alkaline radiator flush then repeating the above flushing.
If you're getting flakes then I'd look at some sort of coolant filter that goes in your radiator hose. If you're getting flakes I'd be worried about the condition of the oil cooler, it's built into the block and uses the coolant to cool the oil. It'd probably be worth popping the cover off for an inspection.
I've had success curing the rust coloured coolant problem by repeatedly filling the engine with water, firing it up for say 20 seconds and dumping it until it goes clear. Then following that up with 1ish hour drive with an alkaline radiator flush then repeating the above flushing.
If you're getting flakes then I'd look at some sort of coolant filter that goes in your radiator hose. If you're getting flakes I'd be worried about the condition of the oil cooler, it's built into the block and uses the coolant to cool the oil. It'd probably be worth popping the cover off for an inspection.
hj 60
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In my hj I think they used the stop leak stuff (never use it, only emergency) so the cooling kept coming out like rust color, this was not coming from the engine for sure, kept flushing 
, repaired 
, and within 30 kilometer started leaking a few cm from the welded spot , then replaced with new rad.
clean as it should be, after using new rad, I never ever use water:
Also read about acid cooling liquid, but that is just a hoax I think: How to test for electrolysis
Tested the old and new coolant with pH test paper, no color difference, try to stay above pH 7
Water has a pH of 7.0 and antifreeze has a pH of 10.5, so a 50-50 mix has a pH of 8.75, and that’s too acidic to protect the cooling system.
The pH value is a way of expressing the relative acidity of coolant. Acidity does cause corrosion.
left side is new, I see no color difference, red is vinegar:
, repaired , and within 30 kilometer started leaking a few cm from the welded spot , then replaced with new rad.
clean as it should be, after using new rad, I never ever use water:
Also read about acid cooling liquid, but that is just a hoax I think: How to test for electrolysis
Tested the old and new coolant with pH test paper, no color difference, try to stay above pH 7
Water has a pH of 7.0 and antifreeze has a pH of 10.5, so a 50-50 mix has a pH of 8.75, and that’s too acidic to protect the cooling system.
The pH value is a way of expressing the relative acidity of coolant. Acidity does cause corrosion.
left side is new, I see no color difference, red is vinegar:
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