Engine bay platic/rubber protection
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Super Member
Joined: Nov 2016
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2008 C350 Sport 4Matic Swap
Engine bay platic/rubber protection
So we all know mercedes uses a lot of plastic in the engine compartment and on key parts through out the car. I was wondering if any of you protect the plastic with any specific product.
I have been using silicon spray on the plastics and rubbers in the engine bay for years and all my hoses/vacuum lines are still pliable with no signs of cracking, this is a 2008 c300 with 240 000km driven in hot summers and very snowy and cold winters.I have been applying it every few months since I got it at 120 000km. My intake manifold is still stock and I focus most of he spraying in there because I know that is the weakest part of this engine, I don't know what mercedes was thinking using plastic intake runners but what can we do other then protect the plastic and make it last longer.
I recently learned silicon spray can conduct and I really lucky I never had electrical issues since I always sprayed all the connectors before winter to make them more water resistant but I have since learned that silicon spray isn't the best option for this, I was since switch to putting di electric grease on every connector I can get to.
Now I read great reviews about 303 Aerospace Rubber and plastic protectant, it was initially designed by NASA so I'm thinking it must be good, hell I've heard of people applying it on their new tires to make them last longer, is this the secret product manufactures aren't telling us so our plastic and rubber parts dry out and need replacing sooner ? I can believe that with how disposable everything is now. I order a bottle and I will see if the results speak for them selves or if its the same garbage they sell at autozone that washes off or dries off after 2 days, for the price I hope it isn't.
I have been using silicon spray on the plastics and rubbers in the engine bay for years and all my hoses/vacuum lines are still pliable with no signs of cracking, this is a 2008 c300 with 240 000km driven in hot summers and very snowy and cold winters.I have been applying it every few months since I got it at 120 000km. My intake manifold is still stock and I focus most of he spraying in there because I know that is the weakest part of this engine, I don't know what mercedes was thinking using plastic intake runners but what can we do other then protect the plastic and make it last longer.
I recently learned silicon spray can conduct and I really lucky I never had electrical issues since I always sprayed all the connectors before winter to make them more water resistant but I have since learned that silicon spray isn't the best option for this, I was since switch to putting di electric grease on every connector I can get to.
Now I read great reviews about 303 Aerospace Rubber and plastic protectant, it was initially designed by NASA so I'm thinking it must be good, hell I've heard of people applying it on their new tires to make them last longer, is this the secret product manufactures aren't telling us so our plastic and rubber parts dry out and need replacing sooner ? I can believe that with how disposable everything is now. I order a bottle and I will see if the results speak for them selves or if its the same garbage they sell at autozone that washes off or dries off after 2 days, for the price I hope it isn't.
Super Member
Joined: Mar 2011
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From: Bay Area, CA
2011 C300 Sport, P1, MM, Wood, Heated FS, DIY rearview camera.
I too heard from youtube that 303 is super, and if the windshield wiper is treated with 303, we only need one wiper, never need to replace it. I bought one bottle and treated my other SUV on the step bar and the rear bumper top (black plastic for loading/unloading). I thought it will make the faded black more black; it doesn't. For UV protection? That'll take long time to know
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Joined: Jun 2011
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From: Canada
A car
I second 303, although I don't bother treating anything in the engine bay...my main issue is salt (FFS), so this year the C is going to the dealership (yes, dealership) for an engine bay wash. Yes, I realize the perils, but the dealer has said they will take responsibility if anything bad happens, and the vehicle is still under EDW, so I'm fine with that. I'd rather get all the crap out.
Some people spray 303 on the tires and wipers. I haven't gone that far yet...seems a bit ballsy, but then again I did just replace my last set of tires b/c they were starting to crack, so maybe I just don't know what I don't know.
Some people spray 303 on the tires and wipers. I haven't gone that far yet...seems a bit ballsy, but then again I did just replace my last set of tires b/c they were starting to crack, so maybe I just don't know what I don't know.
