2017 GLS550 Coolant Leak

[rpaoness]

Unless I'm missing something they don't appear to have the coolant fitting.

[kevm14]

Ah you are correct. I never checked. That's pretty lame on their part. I rarely order from them. My last order was 1 year ago for an axle boot kit.

I can't tell if Warwick has it. Or my phone isn't showing the usual "In stock" type info.

[rpaoness]

The coolant fitting replacement was only a PIA because of access to the rear hose clamp. They left what I assume is a service loop in the 3/8" or whatever lower line that made that easy. All back together and no leaks with a couple hour pressure test.

I was going to change the oil while I have it in and on the lift (4200 miles ish?). Based on test-running with the hood open I believe I should do an idler bearing and I guess serpentine belt change shortly since I think it's noisy.

[rpaoness]

Oh yeah, replacement of the plastic cylinder head plug was really simple. Based on how easy it went in, I hope it doesn't leak/loosen again. Rubber seal molded into the old one seemed hard/old, so hopefully that's why it leaked.

[kevm14]

I was going to change the oil while I have it in and on the lift (4200 miles ish?). Based on test-running with the hood open I believe I should do an idler bearing and I guess serpentine belt change shortly since I think it's noisy.

Generally spin them and listen for noise or spinning that isn't damped by bearing grease. I believe when I did the big one on top the new one wasn't any tighter so I guess you can't just go by "slop.". Noise is probably a better indicator. And it shouldn't spin endlessly.

[rpaoness]

Coolant leak returned. 2 weeks leak free, but leaking again. Reports are that it is from the same place. I wonder what I missed or screwed up.

[rpaoness]

I'm not sure I'll have enough time in the morning to pull the faux-firewall apart in the morning to get a better look at it, but it appears that the plastic fitting-to-heater core hose may have some coolant soaking the reinforcing cords, which makes me think that that it's likely damaged from being yanked on. I'll see if New London has the hose (which hopefully comes with clamps? I didn't see clamps in the parts list?) Looks like it's also not too bad - $15 MSRP.

https://www.mercedesbenzpartsshop.com/o ... 1668300496

[rpaoness]

And…. Not in stock in CT. New London thought North Haven had one but said to check because it might’ve been ordered for a job or 48 hour old status. North Haven said their computer showed one, but they couldn’t find it.