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Coolant leak help

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Old 06-09-21, 06:29 AM
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Coolant leak help

I have an intermittent coolant leak problem. When hot I can often smell burning coolant and on a couple of occasions I've seen smoke come from under the hood. I can hear a hissing and what sounds like dripping on a hot manifold but I can't see anything from under the hood or under the car on a lift. It sounds like it's coming from around the turbos. I removed the UIM and didn't see anything. At this point I don't have any ideas other than to remove the turbos. Looking for insight before I start on that. What's the most likely cause behind the turbos?

Coolant loss is negligible at this point but it's a constant concern when I drive the car now. Just reliability mods on the car including Koyo radiator earlier this year.

Thanks
Old 06-09-21, 11:21 AM
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Haven't seen your user name in a while

Sounds like it may be the 2 tiny turbo coolant hoses. If you have never repalced those, can't hurt to do so. You definitely want to order new OE clamps. Makes install so much easier and they are more reliable than hose clamps.

You can do a coolant system pressure test to help identify where the coolant leak is coming from. Search here or google for that. I've posted about that in the past.
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Old 06-09-21, 12:16 PM
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First thought was those turbo coolant hoses too. A giveaway is if they look bloated. A little fiddly but doable. A set of long-reach needle-nose pliers helps. Good thing is that, last I looked, they’re pretty inexpensive.
I think the chain parts stores sell dye that can help locate leaks too.
Old 06-09-21, 01:25 PM
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You guys nailed it. I put a pressure tester on it and the coolant line was just barely weeping onto the turbo heat shield. Given it's state it's amazing it was holding any pressure at all.

Thanks!


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Old 06-09-21, 01:33 PM
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All I had handy...


Old 06-09-21, 03:42 PM
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That hose failed on me about 10 min after I picked up my FD for the first time. Luckily I had only driven is down the road to get some food instead of the hour drive back home.
Old 06-09-21, 05:25 PM
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If one is that bad I’d change both. And I recommend OEM clamps as soon as you’re able.
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Old 06-09-21, 06:03 PM
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I ordered some from Ray Crowe recently just to have in inventory in case they become NLA
Old 06-10-21, 08:43 AM
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Aftermarket hose will fail in short order. OEM clamps and OEM hose is the only way to go.

The hoses that fail are typically the original hoses from the factory. Mazda updated all the rubber in the coolant hoses later in the 90's, if you get a hose now it will probably outlast the car.

Also that stainless braided parts store hose probably isn't designed for coolant, probably fuel. Change that out with OEM PROMPTLY, that is an easy way to overheat your engine and you're looking at a much more expensive problem.

Dale
Old 06-10-21, 03:09 PM
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Along with a lot of other preventive maintenance, I replaced all the coolant hoses including those in 2005. I bought all of them as a set from Ray Crowe. Sure glad I did that. Those hoses are not something you can just glance at the engine compartment and see.

Last edited by DaveW; 06-10-21 at 04:31 PM.
Old 06-10-21, 04:29 PM
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Originally Posted by DaleClark
Aftermarket hose will fail in short order. OEM clamps and OEM hose is the only way to go.

The hoses that fail are typically the original hoses from the factory. Mazda updated all the rubber in the coolant hoses later in the 90's, if you get a hose now it will probably outlast the car...
In that overheated environment, any hose that uses Nylon or polyester braid will die from an aneurism. It needs to be something like Kevlar (Aramid) that can take the heat.
Old 06-14-21, 05:32 PM
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I've had trouble removing those turbo coolant hoses without shredding them, I recently bought a new set to replace ones that were only 2 years old. Can anyone recommend special tools or other tricks for removing and reinstalling them cleanly? I usually use some cheapo pliers that are curved near the edge and conform to the hose shape a little but they are narrow and tend to cut and tear the rubber.
Old 06-15-21, 08:02 AM
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You need curved hose pliers to grab and twist the hose to break the seal. Squirting some WD-40 on the end of the hose, then working the hose pliers until the WD-40 gets under the hose, helps big time.

If you have pliers that are cutting into the hose time to find new ones

Dale
Old 06-17-21, 11:18 AM
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Yep. Something like this:
Amazon Amazon

although, I'd substitute WD40 for something like soapy water or some simple green that will evaporate relatively quickly.
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Old 06-17-21, 11:42 AM
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I’ve used those ^ for the clamps and hose pliers on the hoses, but iirc one of them is back in there and a little tough.

https://www.harborfreight.com/3-piec...ers-37909.html



Last edited by Sgtblue; 06-17-21 at 11:47 AM.
Old 06-17-21, 08:11 PM
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Originally Posted by Sgtblue
I’ve used those ^ for the clamps and hose pliers on the hoses, but iirc one of them is back in there and a little tough.

https://www.harborfreight.com/3-piec...ers-37909.html
How do those@Sgtblue
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