Stainless Steel 032 121 065 D Coolant Pipe.

Hi there, I am currently overhauling my FSI engine & it will be coming out of the car on Tues 10th Dec. to do the cambelt etc & I also want to replace the death pipe & fix an oil leak fro the sump area.

I am a retired engineer & have experience of rebuilding several race & road cars, so am confident that I could assess if the pipe proposed will do the job or not & aim to have my engine re-fitted & running by the end of January 2025.

As I am in Luxembourg, shipment to me could pose less of a problem than shipping to the UK, so I would be willing to test out the pipe & reoprt back. I was thinking of contacting the company concerned myself anyway, but do not want to tread on anyones toes on this project, by doing so.

If I am happy with the pipe they propose, I would be more than willing to act as a delivery point for a quantity of their products & would be able to bring them to the UK on my next visit, which would probably be in March 2025 at the latest.

Mac, as you seem to be the co-ordinator (?) of this project, please can you let me know if this is the way you want to proceed ?

I hope this will in some way contribute to the A2OC, which is a great source of help to me so far, in the running & upkeep of my FSI.

Best regards.
Martin
That sounds like the perfect conditions for a test fit, so I'm more than happy to accept your kind offer. I don't have any real doubts, as ACS Cooling seem very professional, and the A2 version is a minor variant of a part they've produced for the Golf.
If you can PM me your postal details, I'll pass them on to ACS, as soon as the part is ready. Thanks again.
Mac.
 
Hi there, I am currently overhauling my FSI engine & it will be coming out of the car on Tues 10th Dec. to do the cambelt etc & I also want to replace the death pipe & fix an oil leak fro the sump area.

I am a retired engineer & have experience of rebuilding several race & road cars, so am confident that I could assess if the pipe proposed will do the job or not & aim to have my engine re-fitted & running by the end of January 2025.

As I am in Luxembourg, shipment to me could pose less of a problem than shipping to the UK, so I would be willing to test out the pipe & reoprt back. I was thinking of contacting the company concerned myself anyway, but do not want to tread on anyones toes on this project, by doing so.

If I am happy with the pipe they propose, I would be more than willing to act as a delivery point for a quantity of their products & would be able to bring them to the UK on my next visit, which would probably be in March 2025 at the latest.

Mac, as you seem to be the co-ordinator (?) of this project, please can you let me know if this is the way you want to proceed ?

I hope this will in some way contribute to the A2OC, which is a great source of help to me so far, in the running & upkeep of my FSI.

Best regards.
Martin
Hello Martin,

Hope all is well Sir, it’s been a while since we chatted. Your offer to jump in and help out is absolutely perfect. Both in terms of testing the prototype and also bringing any futures items to our shores where you visit. Splendid offer, thank you for stepping in and assisting the community.

Kind regards,

Tom
 
Hello, pioneers.

Using scotchbrite, a drop of engine oil and chrome polish to clean the area where the death pipe slots in I found that the alloy surface remained uneven after cleaning.
Using only light pressure and a stainless steel pick I was able to gently remove the build up leaving the surface smooth ready for the new part to be fitted.

20241208_203252.jpg


πŸ™‚πŸ‘
 
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@PlasticMac Hi Mac, I got an FSI motor on a pallet but it cannot be fired up. Well done on your efforts. I might be moving out of the country at some point though so not exactly an ideal candidate.

Evros
 
Hello Martin,

Hope all is well Sir, it’s been a while since we chatted. Your offer to jump in and help out is absolutely perfect. Both in terms of testing the prototype and also bringing any futures items to our shores where you visit. Splendid offer, thank you for stepping in and assisting the community.

Kind regards,

Tom
Hi thereTom ; yes hope we can get somewhere with this project. I hope to have completed all my engine out maintenance by early Jan ; date depends on when the β€˜no more death pipe’ gets to me.

Thanks for your RNSE work in the past ; l now get lost less frequently 🀣
 
I dislike the "Death Pipe" moniker very much.
I believe that failure of the coolant pipe has precursors, which are, sometimes, ignored or dismissed as "... it's an FSI, it still drives OK ... "
Ignoring an EML is not uncommon, and on some engines has little consequence. Ignoring an EML in an FSI can be a death sentence.

Benjamin Franklin wrote:
β€œFor want of a nail, the shoe was lost; For want of a shoe, the horse was lost; For want of a horse, the rider was lost; etc”
I'd add:
For want of a scan, an FSI was lost.
Mac.
 
I don’t think there’s an eml associated with death pipe failure, is there?

My understanding was that in best case scenario cases the only warning is a gradually increasing coolant loss, and at worst it’s far more sudden with no warning at all?

I’ve not experienced death pipe failure, but my fsi has burst a few other coolant lines, and there is no warning.
Driving along with no engine lights, and then if you don’t happen to see the coolant temp gauge increasing, the first warning is the coolant temp alarm.
Often, even the coolant level sensor doesn’t seem to trigger when the engine is running.

The only solution is preventative, either by changing the plastic one every 10 years, or switching to the new stainless one when it comes available.
Other than that all you can do is stop the engine the second you notice an issue.
 
I don’t think there’s an eml associated with death pipe failure, is there?

My understanding was that in best case scenario cases the only warning is a gradually increasing coolant loss, and at worst it’s far more sudden with no warning at all?

I’ve not experienced death pipe failure, but my fsi has burst a few other coolant lines, and there is no warning.
Driving along with no engine lights, and then if you don’t happen to see the coolant temp gauge increasing, the first warning is the coolant temp alarm.
Often, even the coolant level sensor doesn’t seem to trigger when the engine is running.

The only solution is preventative, either by changing the plastic one every 10 years, or switching to the new stainless one when it comes available.
Other than that all you can do is stop the engine the second you notice an issue.
There is an EML associated with the failure of the heating element in the ECU controlled thermostat.
Once the ECU is no longer in control of engine temperature, only the mechanical thermostat is left, which doesn't open until 110 C.
Result of ignoring the EML? The coolant is at 110 C all the time.
Keep driving, and the engine will overheat.
At the higher coolant temperature, the cooling system can no longer dissipate the amount of heat required to keep the engine temperature to a safe level.
The lower coolant pipe is, probably, the weakest point in the cooling circuit,so it fails.
Mac.
 
There is an EML associated with the failure of the heating element in the ECU controlled thermostat.
Once the ECU is no longer in control of engine temperature, only the mechanical thermostat is left, which doesn't open until 110 C.
Result of ignoring the EML? The coolant is at 110 C all the time.
Keep driving, and the engine will overheat.
At the higher coolant temperature, the cooling system can no longer dissipate the amount of heat required to keep the engine temperature to a safe level.
The lower coolant pipe is, probably, the weakest point in the cooling circuit,so it fails.
Mac.
I don’t think that this is the case?

The thermostat heater failing is a pretty rare failure, I don’t recall ever actually seeing an example posted on here (though I’m obviously not saying that it never happens)

And besides, in the tests I did earlier this year, there was no significant difference in max temperature anyway even if it did fail

I certainly didn’t get anywhere near overheating it, and that was driving quite spiritedly for the test, too.
 
In my (at this point worryingly large amount of) experience of overheating an FSI, it’s only ever happened due to a massive loss of coolant.
I think it’s the the other way around, the death pipe causes coolant loss and consequently overheating, not vice versa
 
In my (at this point worryingly large amount of) experience of overheating an FSI, it’s only ever happened due to a massive loss of coolant.
I think it’s the the other way around, the death pipe causes coolant loss and consequently overheating, not vice versa
I don’t think that this is the case?

The thermostat heater failing is a pretty rare failure, I don’t recall ever actually seeing an example posted on here (though I’m obviously not saying that it never happens)

And besides, in the tests I did earlier this year, there was no significant difference in max temperature anyway even if it did fail

I certainly didn’t get anywhere near overheating it, and that was driving quite spiritedly for the test, too.
If a driver ignores the EML, the cause of the EML is unknown.
If it were the ECU controlled thermostat, again, with the EML being ignored, that failure would be unknown, wouldn't it.
I don't share the theory that the coolant pipe just fails. I think it fails due to coolant flowing through it being significantly higher than it should be.
I accept we'll never know, of course.
Mac.
 
I think it fails due to coolant flowing through it being significantly higher than it should be.
1733753695897.png

With the thermostat unplugged, shown in red, I just don't see how the temperature can be described as 'significantly higer than it should be'
 
The amount of heat energy, that the cooling system has to dissipate is proportional to the amount of work the engine is doing.
A engine will overheat, when the amount of work the engine is doing, creates more heat than the cooling system can dissipate.
I don't think that In either of your runs, with, and without mapped cooling, does the engine reach a work rate that would generate enough heat energy to exceed the cooling systems capacity.
Comparing the two plots, there are quite a few periods where the engine temperature under ECU control is noticeably lower than under control of the mechanical thermostat.
So, during those periods, the engine is running at a higher temperature than the engine operating conditions justify.
Increasing the engine load, (and the heat energy that needs to be dissipated), it's likely that under mechanical control, the engine may overheat. Why do I think that?
Because the thermostat will not open until the coolant temperature exceeds 110C, by which time the engine is at a much higher temperature.

Under mapped control, the ECU would react to the rise in temperature by opening the thermostat, before the overheat condition was reached.
I think of mapped cooling as controlling the engine temperature, whereas a mechanical thermostat only controls the coolant temperature.
Mac.
 
The radiator should be capable of regulating the engine temperatures even at maximum load, if your mapped cooling system is working then you can see this in practice by flooring it at 4-5k and watching the temperature drop from down from 110 degrees, if it was unable to dump enough the heat then the engine temps would instead rise.
If this was not the case then the entire mapped cooling sytem would not work, as it only kicks in under high engine loads.
 
The actual engine temperature is irrelevant though, the 'Death Pipe' is only heated by the coolant, so any damage that might be caused to it as a result of the mapped cooling system being inactive can only come from an increase in coolant temperature, which as shown in the graph above, in my experiment was marginal at best.
 
The radiator should be capable of regulating the engine temperatures even at maximum load, if your mapped cooling system is working then you can see this in practice by flooring it at 4-5k and watching the temperature drop from down from 110 degrees, if it was unable to dump enough the heat then the engine temps would instead rise.
If this was not the case then the entire mapped cooling sytem would not work, as it only kicks in under high engine loads.
My understanding is that mapped cooling is active under all operating conditions.
Mac.
 
Nah it most of the time the thermostat heater is turned off, it only turns on if the engine load is high. Purple line in this graph.View attachment 132572
My impression from the graph is that the ECU is controlling the temperature throughout.
The increase in radiator outlet temperature, (which indicates that the thermostat is open), seems to correlate with the rise in duty cycle, (which indicates the ECU has acted to open the thermostat).
The actual engine temperature tracks the setpoint pretty well. The maximum difference between setpoint and actual is around 10C, with the average, by my estimate, around 5C.
I don't see any evidence of the mechanical thermostat opening.

I'm curious about the Radiator Outlet Setpoint data, (light blue plot). I can't see any correlation between that Setpoint and the Actual. I wonder what function it might have, (if any)?
Mac.

Note: I am considering moving the last few posts to a new thread. This thread is specifically about the stainless steel coolant pipe, which ACS Cooling are producing for us.
Does anyone object?
 
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Hello, pioneers.

Using scotchbrite, a drop of engine oil and chrome polish to clean the area where the death pipe slots in I found that the alloy surface remained uneven after cleaning.
Using only light pressure and a stainless steel pick I was able to gently remove the build up leaving the surface smooth ready for the new part to be fitted.

View attachment 132540

πŸ™‚πŸ‘
Any ideas what the "deposit" was?
How close is the fit, between the coolant pipe and the engine housing?
I'm wondering how much heat from the engine itself (not from the coolant), the coolant pipe is exposed to.
I realise your example is a BBY, but I'd think the fit will be the same as the FSI.
Mac.
 
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