This is FANTASTIC work fellow grease monkeys! This kind of known, pending failure keeps me from driving my Macan more than 2 hours from home. I reached out to Porsche N.A. for some proactive relief and they told me to go scratch! Really, this could be the top value/time saving workaround I’ve come across in 40 years of home wrenching. Bravo!

 

@Santirx good to know you can’t re-use the fittings, where did you get new fittings for $20? You also mention buying the OEM pipe since this retrofit would last longer than factory,, but that OEM pipe just to use the fittings is $100+ right?

 

I didn’t get fittings for $20, I was referring to someone else’s posting where you can get an aftermarket tubing for $20. In my case, I already had the tubing from Porsche, as I was paranoid about this failing on me… I was already planning on replacing the tubing preemptively.

I’m also very grateful to @dethbrd for this finding, as it turned this replacement from a huge nightmare to just a nice easy one… and as he said in prior post, it will last the life of the car.

 

Video is out. I prioritized this one over the other close to 10 videos I’m currently editing… (I hope I had more time, but it is what it is)…

Watch on YouTube, rather than from the link…

How could Porsche get this so WRONG! The Coolant Vent Tubing Story & the EASY FIX... Macan 1st GEN

 

This is awesome. Great job @Santirx! Definitely on the to do list.

I can't help but wonder why Porsche would do it in such a complicated way though. It's baffling, but there has to be some reason. It would probably actually be cheaper to produce with this simplified routing.

Just a note for those planning to use silicone hoses - don't use standard worm clamps. They can dig into and cut the outer silicone casing. They make special clamps with a "lining" for these hoses. I think the clamps @Santirx used are most likely fine. I've also seen some discussion online that silicone hose clamps may need to be retightened occasionally, but I'm not sure how much truth there is to that.

Also, here's a comparison of EPDM (rubber) and silicone hoses from Gates, who makes both kinds: https://www.gatesaustralia.com.au/~...res/cooling-system-and-hose-products/epdm-vs-silicon-flyer-ausnz-april-2020.pdf

 

Nice work on the video @Santirx . Can I ask how many feet of hose you think is needed (looks like 5 feet would do)? Additionally, have you identified the quick connect to the coolant distribution hub (would be nice to use a straight connector).

Thanks for all the research.

 

Nice work on the video @Santirx . Can I ask how many feet of hose you think is needed (looks like 5 feet would do)? Additionally, have you identified the quick connect to the coolant distribution hub (would be nice to use a straight connector).

Thanks for all the research.

5ft is fine for this project…. I got 10ft and ended up with more than half excess.

I haven’t identified the right fitting yet. I still need to measure fitting for right size.

 

Just reusing the fitting and tying up the hose somehow like I did with a tie wrap/clip will be just fine.

I said I was going to buy a new one, but the old one is holding up well, so I won’t replace it.

 

By know you probably know I want things to look as OEM as possible. Given there are no 1.75” to 0.5” OD hose separators that I could find to hold the new hose in place (rather than tying it with a single tie wrap), I decided to design and 3D print my own….

This is prototype # 1 installed in the car… let me know what you think…

It is designed to still use tie wrap on the larger hose, but a clip-on clamp on the smaller one.

 

This is prototype # 1 installed in the car… let me know what you think.

Great work!

Maybe a little ridge along the outside edges to keep the zip tie from excess lateral movement?

 

Oooh I love it!

 

Yeah, I was thinking the same thing…. Latest design. Will be printing and testing tomorrow…

 

2nd prototype printed in polyC. I think design is now good. Printed in polyC to determine if it can withstand the temperatures in the engine bay…

 

Completing coolant vent hose project with some nice hose separator clamps

 

The clamp looks great, a nice finishing touch. If you're willing to make some up for sale, please let us know. I'm going to dig in a little and see if I can identify that quick connect and where to purchase.

 

Once I finish with prototype testing, I’ll let you know…. I’m doing a full week test inside engine bay to determine if polyC can withstand temperatures without getting soft and deforming.

This is now prototype # 4. It has dual tie wrap to better secure both hoses.

 

I see a complete coolant vent pipe replacement kit in Santirx’ future…

 

I'm just going to throw this out there - there are multiple online 3D printing services that can print for you in just about any material you can think of. So if there's something out there that would be perfect, you could have it made in bulk for a pretty reasonable price. It's less cost effective when you talk about a one off print, but still not bad if you don't have a 3D printer or don't want to buy some exotic material for a printer that you do have. Craftcloud is a service I've used before and they do have a long list of options. You can easily upload a design and see pricing on various options: Material Guide

All of that said, polycarbonate is probably fine for this application, although there might be something better (more flexible, tolerates higher temps, more chemical resistant, etc).

 

I'm just going to throw this out there - there are multiple online 3D printing services that can print for you in just about any material you can think of. So if there's something out there that would be perfect, you could have it made in bulk for a pretty reasonable price. It's less cost effective when you talk about a one off print, but still not bad if you don't have a 3D printer or don't want to buy some exotic material for a printer that you do have. Craftcloud is a service I've used before and they do have a long list of options. You can easily upload a design and see pricing on various options: Material Guide

All of that said, polycarbonate is probably fine for this application, although there might be something better (more flexible, tolerates higher temps, more chemical resistant, etc).

PolyC holding very well so far, after 100 miles driven…. One thing I noticed is that this vent doesn‘t get very hot. And the larger hose has insulation. So, the issue is really with the environmental temperature of the engine bay, rather than the hoses themselves.

 

I have a bunch for 7-10 hour drives coming up this summer for hockey camps. Last thing I want is for that coolant line to rupture mid-trip.

2016 S.

Date stamping on under intake hoses was 07/20. Meaning the first owner, poor soul, had the misfortune of already having this issue in their ownership. Line from overflow tank was stamped 2015. So they got ~5 years on the OE hoses.

Coming up on 4+ years with the 2nd set. Time to change. Also found the vent tube side connector was cracked just after the 1st barb. Pulled it off from vent and it came apart in my hand - line and connector. Resorted to direct connecting the hose to nipple. Tight fit, not too worried about it popping off.

Many thanks to Santrix for video. Very straight forward repair. Sub 1 hour.

 

It is interesting to see the variability in failure occurrence. It seems to follow random failure pattern. A few reported 60K miles failure, others (like me) 140K miles without failure. And many in between.

I’m sure there could be multiple factors contributing to this issue, like temperature, chemical composition of coolant (I.e. degradation with time if not changed; water/coolant mix ratio; brand?), etc…

Wonder if those who are seeing early failures have short or long commutes, heavy (traffic jams) vs light highway traffic, predominantly cold vs hot climates, etc…

In my specific case: (1) 35 minute commute, mostly highways with avg speed of 50mph, but mostly 80mph at highways; (2) moderate heat to extreme cold (Summer and Winters in US North East). Have replaced my coolant often (at least every 40K miles).

 

In my 60K-mile failure case, I live in the US West (SF bay area) with moderate temperatures year-round (mostly garaged). Never changed the coolant. Mix of local and highway miles.

 

Thanks to Santirx's YouTube video, I was able to fashion a coolant vent line using the "$100 connectors" from the OEM line which was delivered yesterday (ordered from Pelican Parts, part #: 946-106-026-60-OEM). I started up the vehicle and waited for the temperature to reach 200F. It stayed at 200F while idling for 5 minutes. I put everything back together after checking for leaks.

 

I have received some questions about this tubing and the certainty I have that it doesn’t connect anywhere else. And although I inspected this complete route with a borescope and determined that in fact it is a vent from the front of the engine going through center coming out back and doing this crazy loop until it connects to vent valve (and @dethbrd who discovered and developed the new repair process, did an actual visual inspection and confirmed the same thing), I wanted to put this to bed by showing this in an engine diagram…

I highlighted route in yellow. You can clearly see that this tubing doesn’t connect anywhere else.

 

unbelievable how the engineers routed that tubing

 

Here is the pipe line!

 

Excellent. Thanks!

 

Maybe Porsche issued design of that part to an intern…

 

Nah… this was a very clever design…. Ready to burst exactly when your warranty runs out. That requires a lot of design experience, don’t you think? 🙂

 

@Santirx I’m getting ready to do this as my pipe just burst. In my mind I was just going to cut the plastic pipe, take the connectors off and run heater hose…at the end of your video it looks like you removed the rear pipe…I had planned on just leaving it. Looking at your highlighted diagram seems like it should be fine to leave in place. Thoughts?

 

You can leave in place, but try to secure it somehow so that is not dangling loose in there. That‘s precisely why I removed it, because I didn’t want this to be dangling…

 

Gentlemen:
Just to clarify, in both @Santirx 's second parts diagram (#11, or also labelled #12 thru #18) (Post 257) and in @Svetoslav Kostov's photo (Post 259), the part I have circled in red is not connected to the part we are removing, correct? It just happens to be shown in the parts diagram and that photo, and likely runs alongside our "bad" part, correct? We are leaving the part circled in red connected and in the vehicle, correct?

 

Gentlemen:
Just to clarify, in both @Santirx 's second parts diagram (#11, or also labelled #12 thru #18) (Post 257) and in @Svetoslav Kostov's photo (Post 259), the part I have circled in red is not connected to the part we are removing, correct? It just happens to be shown in the parts diagram and that photo, and likely runs alongside our "bad" part, correct? We are leaving the part circled in red connected and in the vehicle, correct?
View attachment 285145


View attachment 285146

Correct. That's the hose that connects to the bottom of the Coolant Reservoir. DO NOT REMOVE THAT ONE!

 

I just finished this project this morning. I left all the bad stuff in there and ziptied them away. The business end simply goes from the heads to the tee, to that junction on the air filter

 

Amazing. I was watching some videos on how to remove the whole god **** intake and ran into this, thanks YouTube algorithms! I was thinking of getting this done with a intake valve cleaning but this seems like a much more sensible repair.

I imagine they might have done this design to get the coolant to heat up faster? Not sure.

On my car, on the Carfax, it shows this repair at a Porsche dealer:
8/2021 - 82k miles
Vehicle serviced
Antifreeze/coolant flushed/changed
Cooling system checked
Engine cover removed and reinstalled

I can't imagine this is anything but this part failing right? I believe the in service date of the car is 12/2016 as a 2017 model. This would line up with the 5 year mark. Meaning my current hose is about to be 3 years old soon assuming it was done in 8/2021.

 

I imagine they might have done this design to get the coolant to heat up faster? Not sure.

I don’t think so. This is a vent, so, normally you won’t have heat exchanged in a vent unless it is for heat recovery from vent to something else…. but this is not designed as an heat recovery system and in addition plastic is a poor heat conductor, so, if heat exchange is of primary concern here, they would’ve specified a metal tubing.

I’m trying to rationalize the design intent, but have no idea why they chose this way…

Good luck with your repair.