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29th March 2019, 19:24 | #1 |
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noise when air con switched on
Hi,
When the air con is turned on there is a noise that changes with revs. Its not the whooping sound that can happen but a whirring type of sound. The engine seems a tad harsher when revved too. When the air con is turned off, its much quieter. Air con is cool but not as cold as I know they can get. Am I looking at belts here or compressor? |
29th March 2019, 19:35 | #2 | |
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Cheers Ian
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29th March 2019, 19:47 | #3 |
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check the crankshaft pully and the belts.
Kev |
29th March 2019, 20:31 | #4 |
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I had this. One garage suggested a new compressor was needed. I duly sourced one then read somewhere the noise may be due to low refrigerant/oil mix in the a.c. system. Sure enough an air con service sorted it out. That's all it was.
Air con service is recommended every 2 years I think so it might be worth considering before jumping to big repairs especially when you've noticed a drop in the systems performance. Sent from my SM-G935F using Tapatalk |
29th March 2019, 21:35 | #5 |
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Dtto Coups.
Mine had a revs variable whirring noise which disappeared after a fresh regas/lube job. It just needs a regas. TC |
30th March 2019, 07:15 | #6 |
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Hi Ian,
As you can see, there are a variety of suggestions for your symptoms. As you have a diesel, I'm with Kev75. We've encountered this several times before. The extra load presented by the air conditioning compressor highlights a failing crankshaft pulley. I note your comment about engine harshness increasing. A low air conditioning refrigerant charge, a failed low speed radiator fan or corroded condenser would not normally result in any abnormal noises or engine harshness. If you want to pursue this avenue, I would begin with the 'demist test' to check the radiator/condenser fan because you cannot assess the system's performance properly unless this is working. Simon
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30th March 2019, 08:01 | #7 |
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My air con specialist tells me that most systems lose around 5% of their contents each year, so after year 1 = 95%, year 2 = 90% approx and so on.
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4th April 2019, 00:06 | #8 |
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If you have a "grindy" compressor, never, ever run it again if you notice it making noise. Get the system re-filled, and if it is not damaged, it should return to almost silent operation.
If it does not, then it will likely slowly get worse over time and would eventually need replaced. |
4th April 2019, 06:33 | #9 |
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What's the latest on this Ian? Have members' suggestions been helpful? Have you made any progress?
Simon
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4th April 2019, 07:01 | #10 | |
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What has to be remembered when the gas comes out so does some of the oil so just getting the refrigerant topped up every few years as Halfords usually do will end up with a system dangerously short of oil. |
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