Looking for coolant adapter
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Joined: Nov 2024
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Looking for coolant adapter
Hello all,
Recently purchased mac tools cooling system pressure tester and will need to get an adapter to pressurize the cooling system and find a leak I have.
I already spent over an hour trying to find adapter. My understanding is snap on, mac tools, OEM tools, and other brands will be compatible, but just can't seem to find any info on which size I need. My understanding is opening on W166 is about 71 or 72mm. If you know which one I need, please let me know. Thanks
Recently purchased mac tools cooling system pressure tester and will need to get an adapter to pressurize the cooling system and find a leak I have.
I already spent over an hour trying to find adapter. My understanding is snap on, mac tools, OEM tools, and other brands will be compatible, but just can't seem to find any info on which size I need. My understanding is opening on W166 is about 71 or 72mm. If you know which one I need, please let me know. Thanks
Thread Starter
Junior Member
Joined: Nov 2024
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My research so far shows
Pressure kit I got from amazon has adapter that fit as 72mm which got me really confused. Ordered adapter on Mac Tools and will give update when item arrives.
62mm x 4mm
Pressure kit I got from amazon has adapter that fit as 72mm which got me really confused. Ordered adapter on Mac Tools and will give update when item arrives.
Last edited by pahanorlando; Nov 4, 2025 at 11:27 AM.
Thread Starter
Junior Member
Joined: Nov 2024
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Thanks a lot for all these measurements!
I ordered initially this kit on and on this one, adapter 13 is the one that fits, but I am unable to create any pressure with the pump.
I decided (not sure wisely or not yet) to go more expensive route and ordered used mac tools pressure pump and new mac tools adapter. It is definitely more expensive, but I am confident there will be no leak air issues.
I ordered initially this kit on and on this one, adapter 13 is the one that fits, but I am unable to create any pressure with the pump.
I decided (not sure wisely or not yet) to go more expensive route and ordered used mac tools pressure pump and new mac tools adapter. It is definitely more expensive, but I am confident there will be no leak air issues.
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Well, after trying that amazon kit again, it worked lol Turns out I got expensive mac tools for no reason
Anyways, it appears leak is coming from the radiator itself. Here is the video, please let me know if you think its not radiator. There is hose nearby, but I don't see any leak coming from it.
Here is another video using camera, but I don't think it shows much
I already started looking for radiator replacement and found Denso radiator for about $165. Do you think its a good option? Or is there better or cheaper alternative?
Thanks
Anyways, it appears leak is coming from the radiator itself. Here is the video, please let me know if you think its not radiator. There is hose nearby, but I don't see any leak coming from it.
Here is another video using camera, but I don't think it shows much
I already started looking for radiator replacement and found Denso radiator for about $165. Do you think its a good option? Or is there better or cheaper alternative?
Thanks
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Joined: Jun 2025
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From: Australia
2014 ML63, 2018 GLC43, 1929 DB victory six sports roadster
There is quite a few pipes and hoses coming in on that side. I’d be trying to pinpoint the actual leak before buying a radiator. My main bottom hose was leaking at the water pump inlet. I replaced the complete hose. I still have a very slow leak I haven’t been able to find. It left a tiny drip on the garage floor once but that’s it. I need to put it up on the hoist to get a better look.
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Thanks, in mine its just lower radiator hose. The other two lines are missing, probably because I have base ML350. I might take radiator fan out first though to inspect further.
UPDATE: Just pulled out radiator fan and still unable to see exact location of leak, its somewhere behind that side of the radiator. Lower radiator hose is clearly not leaking there, so I'd say its safe to assume its the radiator.
UPDATE: Just pulled out radiator fan and still unable to see exact location of leak, its somewhere behind that side of the radiator. Lower radiator hose is clearly not leaking there, so I'd say its safe to assume its the radiator.
Last edited by pahanorlando; Nov 14, 2025 at 03:42 PM.
