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YOUR RESEARCHBrown scum on surface of coolant following rebuild
Leading reported evidence
Check coolant there was a light layer of brown scum
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Performed · outcome unconfirmed · Original poster
However having recently checked the coolant there was a light layer of brown scum on the surface which was easily wiped off with a tissue.
Brown scum on surface of coolant following rebuild
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Leading evidence: 'Check coolant there was a light layer of brown scum' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check coolant there was a light layer of brown scum' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Performed · outcome unconfirmed
I ran clean water through the car for some time until it ran clear before refilling and it's been fine ever since.
Brown scum on surface of coolant following rebuild
Clean water through the car
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Suggestion
I ran clean water through the car for some time until it ran clear before refilling and it's been fine ever since.
Brown scum on surface of coolant following rebuild
Fill with fresh coolant
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Suggestion
They'll probs recommend flushing out and filling with fresh coolant.
Brown scum on surface of coolant following rebuild
Recommend flushing out
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Suggestion
They'll probs recommend flushing out and filling with fresh coolant.
Brown scum on surface of coolant following rebuild
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9 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
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I've recently had my 3.4 engine rebuilt by hartech following an ims failure. I kept the cost down by removing and recording the engine myself - a full write up is in the pipeline so hopefully I'll be able to share my experiences in the not too distant future.
Luckily for me after refitting the engine it fired up fine with no leaks, oil pressure and water temps all good. Following the running in procedure I'm up to about 130 miles - as mentioned all has gone smoothly. However having recently checked the coolant there was a light layer of brown scum on the surface which was easily wiped off with a tissue.
Is this something that one should expect after a rebuild? Could there be contamination from any assembly lube? The coolant was drained and refilled so could have pulled some crap through the system. Interested to hear if anyone experienced similar.
Greg
I
have
also pinged Hartech an email as well, just awaiting a response. I am curious to hear if anyone else had experienced this.
Since this is a specialist Porsche website with lots of knowledgeable and experienced members who like to talk about their cars I often learn a lot from these forums. I could just speak to Hartech and crack on but in the spirit of things It's nice to get information from a variety of sources and discuss the issues with fellow enthusiasts
Your cooling system has been in use for 15-20 years so it won't be immaculate inside. I recently put in a LTT and there was sludge in the system, but I think someone had used one of those leak sealing solutions at some stage. I ran clean water through the car for some time until it ran clear before refilling and it's been fine ever since.
What was the coolant you drained out like? Unless you rinsed it out, I would expect a small amount of 'muck' in a system that had been rebuilt. Keep an eye on it.
Drive it and monitor it .. if it continues then oil cooler is a possibility .. thats not something an engine rebuild would address ( we only fix what we can see or know about ).. there are other issues which again would not normally be seen on a rebuild but ..
For now keep an eye on it and see if its an actuall problem .
Not at all, speaking to Hartech is an entirely sensible suggestion given they rebuilt the engine.
I had a chat with Grant at Hartech and essentially he said the same as you did deMort - just continue to use it monitor it.
Hopefully it will be just a one off. I did put a new oil cooler on the engine but I could of course have done a poor job of fitting it
I will monitor the situation
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