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Marty, ASE Certified Technician
Category: Mercedes
Satisfied Customers: 54832
Experience:  Bosch Certified Master Technician with over 35 years experience in the automotive industry.
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Sweating in distributor caps on 1990 500 sl

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sweating in distributor caps on 1990 500 sl

Hi, this is a pretty common problem on this motor. If you haven't replace the caps. rotors and ceramic plate under the rotor I would suggest doing so. If everything has already been replaced I would suggest drilling an 1/8th" hole in the bottom of each cap to allow the moisture to vent.

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Customer: replied 1 year ago.
Hi Marty.Have carried out all your suggestions,Have had the caps renewed twice by merc dealers at a cost of £400 to no avail am currently removing the caps at approx 3 month intervals,drying them out then giving a light spray of wd40 before re fitting.This appears to be my only option which is to say the least a pain,Just to let you know what I have done previously.I have cleared all the venting system on the engine and regularly changed the oil.Any further ideas would be most welcome thanks Jeff

Hi Jeff, I have seen that round ceramic plate underneath the rotor actually sweat. Replacing the plate seemed to help. Also, if the car is not used often these cars are just prone to this. Starting the car and bringing it to operating temperature once a week would help.

Customer: replied 1 year ago.
Hi Marty,thanks for the tips I haven't tried these so i'm hopeful.Cheers ***** ***** thanks,regards Jeff.

You're quite welcome.

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