V6 aircon burny smell

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Carlwhite78
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V6 aircon burny smell

Post by Carlwhite78 » Sat Feb 20, 2021 8:44 pm

Our V6 (as lovely as she is) has an interesting habit I'd welcome an opinion on if anyone is willing? When we have the heater on when driving and come to a stop there is a burning rubber smell coming through the vents, but only at a stop and once things have warmed through.

Is this a belt that need changing and if so, where how and what?!?!??!?! :shock:

If not, do we need to run for cover?
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g8dhe
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Re: V6 aircon burny smell

Post by g8dhe » Sun Feb 21, 2021 9:23 am

Its your cam seals! They leak oil with age, that then runs down the sloping engine and onto the exhaust manifold where the heated/burnt oil fumes get blown back under the vehicle into the air con air intake, hence why it only appears at a stop! The oil will also be clogging up your alternator ventilation and in time that will overheat. So when under the front because its difficult to access on the V6 get your Cambelt changed, oil seals, consider the water pump as well and at the same time get the garage to clean out the alternator!
Geoff
97 V6, AFT, full side conversion.
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Carlwhite78
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Re: V6 aircon burny smell

Post by Carlwhite78 » Sun Feb 21, 2021 2:02 pm

That's not what you want to hear! :shock:

The cam belt was replaced in September so thankfully that doesn't need doing which is one saving grace.

Is there anything I can look out for that would be a tell tale sign that this is the case? Is it expensive to sort and what's the impact if we don't get it sorted quickly enough?

We'd wondered if if was one of the belts attached to the aircon system that needed replacing as we can literally only smell it when the fan has been on - when we park its also noticeable when getting out of the bongo but again, only when the fan has been on.

Really appreciate your input!!!!!
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Re: V6 aircon burny smell

Post by g8dhe » Sun Feb 21, 2021 3:22 pm

The only belt is that which drives the compressor for cooling the air, can be seen under the front passenger side, normally you would hear squealing I think, but might be worth checking that the compressor hasn't seized up the belt is coupled to the compressor by an electromagnetic clutch, which is turned on when cooling is needed. The oil on mine ran down the offside of the engine and wasn't visible as such, needed the undertray removing to see the problem, we first noticed it at traffic lights and similar when there was a slight tail wind.
I used some additive to the oil for a good 6 months until the cam belt needed doing to avoid the extra costs it seemed to work OK.
original_48_seal_conditioner.png
Geoff
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Carlwhite78
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Re: V6 aircon burny smell

Post by Carlwhite78 » Tue Apr 06, 2021 6:02 pm

Geoff - you called it lol! Small leak on drivers side . . . . can you remember how much it was to get repaired? With the Forte Seal additive, is it as simple as adding the tube to the oil tank or does it need additional work?
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Re: V6 aircon burny smell

Post by g8dhe » Tue Apr 06, 2021 8:25 pm

I used the Forte seal for quite a while, just simply add it into the engine oil, under the drivers side seat. I waited until the cambelt needed doing and then had the belt, and all the seals replaced, as most of the cost is in getting to the front of the engine, as I say the parts are cheap! I think it was around £600 at the time several years ago now, also consider the water pump being replaced whilst at the front and make sure that the oil isn't getting into the alternator and blocking the ventilation ducts up as otherwise you will replacing the alternator as well when it blows its diode pack from overheating.
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Carlwhite78
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Re: V6 aircon burny smell

Post by Carlwhite78 » Tue Apr 06, 2021 8:32 pm

Thanks matey!!!!! :D
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Powellct
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Re: V6 aircon burny smell

Post by Powellct » Fri Apr 09, 2021 1:07 pm

Oh cock. I have that oily smell on our V6 too - cambelt and crank seal have been done, not sure about cam seals. Is that going to be a case of dropping the tray to look, Geoff? It's only just started, ostensibly because it's not been run a lot.
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Re: V6 aircon burny smell

Post by g8dhe » Fri Apr 09, 2021 2:41 pm

Probably, I never noticed anything visually on mine from above, but could just see it around the exhaust manifold and more importantly I could see the smoke/smell that was being generated when the passenger seat was up. Started using the additive and kept on adding it for quite a while I can't remember how long, until the timing belt was getting close to its renewal date, then had them done. The alternator failed quite a bit later on, but when inspected it was full of congealed oil hence the overheating and death of the diode pack.
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Re: V6 aircon burny smell

Post by Carlwhite78 » Fri Apr 09, 2021 3:48 pm

Oh cock indeed! Took mine this morning to be checked and have leaking cam seals and other such nastiness that comes with a large price tag. Once the under tray was removed it was clear that there was a bigger problem than anticipated. Have booked for new cam belt (although was done recently by previous owner it will be effected by the oil so need replacing), and lots of new engine bits that made my eyes not only water but bleed! Still better to get it sorted before it goes horribly wrong at the arse end of nowhere... :shock:

FYI - there was no other indicator on ours other than the smell as the leak isn't visible from above and the under tray hid the drips.
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Re: V6 aircon burny smell

Post by Bob » Fri Apr 09, 2021 4:30 pm

Sorry to hear this will cost £££. :(

But thanks for then useful update. 8)
Powellct
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Re: V6 aircon burny smell

Post by Powellct » Sat Apr 10, 2021 8:56 am

I'm not sure I want to ask this question - is it an "at home" job? Is access from up top, or would it need a lift? I assume the timing is old fashioned with dots rather than locking pins. Do the cams need to come out? I'm ex trade, but also 57 with arthritis - but 600 notes upwards makes me blink a bit.
Last edited by Powellct on Sat Apr 10, 2021 8:59 am, edited 1 time in total.
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Re: V6 aircon burny smell

Post by Powellct » Sat Apr 10, 2021 8:56 am

Oh, sorry - it it worth whipping the alternator off and cleaning it in the interim?
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Re: V6 aircon burny smell

Post by g8dhe » Sat Apr 10, 2021 9:38 am

I can't visualise it being at all possible to do from the top! The V6 engine is a tight squeeze in the engine compartment.
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Re: V6 aircon burny smell

Post by Powellct » Sat Apr 10, 2021 11:21 am

That's rather made that decision then. I'll whip the tray off and have a squint, then have a chat with the local garage.