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mik

"Scuff" from top of engine?

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Popped out this morning to pick something up. Car garaged afte4 being washed a couple of days ago.

There is a "scuff" sound coming from the top of the engine - audible mostly at the drivers side engine vent on the rear hatch.

Not a whine, rattle, scream or rumble - best sound i can liken it to is the scuff that you get off your brake discs if you wash the car and then dont drive it for a couple of days. It is continuous as opposed to scuff-nothing-scuff-nothing. Sounds like something static brushing against something that is rotating.

Appears to be coming from around the belt end of the charger (hard to really tell), and does seem to change with engine speed - although it doesnt get louder or more insistent and therefore dissapears a bit as other noises increase with revs.

Oil is fully topped up. No signs of any oil leaks or split hoses.

Any obvious or common culprits? Does the charger have a separate oil supply? . Should i grease up the charger belt just incase? ;)

 

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Upgrade today to remove Google ads and support TLF.

Also - anyone know what this little valve is for. It seems to feed into something that then feeds into the charger (?).

valve on my car is fully closed (ie full clockwise). Would be interested to know if yours is closed or open?

dXh69gO.jpg

 

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Actually - does the charger even have oil? Or is it all sealed bearings?

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5 hours ago, mik said:

Also - anyone know what this little valve is for. It seems to feed into something that then feeds into the charger (?).

valve on my car is fully closed (ie full clockwise). Would be interested to know if yours is closed or open?

dXh69gO.jpg

 

It’s not 100% clear from your photo but are you talking about the vacuum lines running from the plenum/supercharger?

If so, they connect to a solenoid which connects to a flap inside the airbox. At certain RPMs, the flap opens (hence increasing the total airflow through the air box). FWIW, these flaps are removed from the Ev400 onwards. 

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It certainlh looks like a vac line its on. The green plastic "cap".

Just wondering if it should be wound tight clockwise.

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Ah, I’m talking about the little black box (with the orange hose running into it) to the left of your arrow. I’m not sure what function the green cap plays, I’m afraid. 

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On 27 December 2017 at 12:49, mik said:

Popped out this morning to pick something up. Car garaged afte4 being washed a couple of days ago.

There is a "scuff" sound coming from the top of the engine - audible mostly at the drivers side engine vent on the rear hatch.

Not a whine, rattle, scream or rumble - best sound i can liken it to is the scuff that you get off your brake discs if you wash the car and then dont drive it for a couple of days. It is continuous as opposed to scuff-nothing-scuff-nothing. Sounds like something static brushing against something that is rotating.

Appears to be coming from around the belt end of the charger (hard to really tell), and does seem to change with engine speed - although it doesnt get louder or more insistent and therefore dissapears a bit as other noises increase with revs.

Oil is fully topped up. No signs of any oil leaks or split hoses.

Any obvious or common culprits? Does the charger have a separate oil supply? . Should i grease up the charger belt just incase? ;)

 

I had something similar on my V6 Exige whilst on holiday in France during the summer. It started on the morning after driving long distance in torrential rain but disappeared again after a few miles in the dry so I just put it down to the supercharger belt pulleys gaining a bit of corrosion overnight whilst wet. As you say, it's rather like the brake discs going rusty after the cars been washed or driven in heavy rain.

Take the car for a longer run and see if the noise goes, as mine did.

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On 12/28/2017 at 03:38, mik said:

Actually - does the charger even have oil? Or is it all sealed bearings?

I doubt it is all sealed bearings. One end may be, but the other end has gears to keep the two impellers timed to each other. I would presume oil in there.

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That would makes sense. I cant find any info on changing or top-up though, so assume it is designed to be lubed-for-life.

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From what I read, they do have oil in them, pre-filled from factory, and not entirely user serviceable. A member on LT with a new 400 had the "snout seal" go bad in the SC and it sprayed oil everywhere. 

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All sorted, with the very professional help of Mr Craig Moncrieff. B-)

For the sake of anyone searching in the future : Turned out to be a combination of two things.

1. Alternator bearing shot. New alt required. Sourced outside of uk to save me £s.

2. Drive belt ageing and becoming stiffer in some sections. 

I hadnt realised previously (as i hadnt really looked) that the charger belt isn't separate - a 3m+ long belt covers all normal ancillaries too.

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