Author Topic: Engine bay drain holes  (Read 1617 times)

mauro12

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Engine bay drain holes
« on: December 16, 2022, 11:45:53 »
Hello guys , I realized many times that during rain or when I wash the car , I have a bit of water entering from the hole near the wiper motor . I believe that hole should be plugged . I attach here some photos , can you confirm me that these holes needs to be plugged ? I put a temporary plug in one of those but is made of plastic and is not sealing properly . Probably the hole marked in yellow is a real drain hole and should not be plugged .I hope you can help me . Thank you
Mauro Pisani
250sl 1967 5speed zf manual

BobH

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Re: Engine bay drain holes
« Reply #1 on: December 16, 2022, 13:20:42 »
Pawel put together a list of drain holes and plugs, see here

file:///C:/Users/Bob/Downloads/Water%20drains_amended%2009_04.pdf

On my car the hole by the wiper motor is plugged, i can't see a need for a drain here, as the cowl slopes down to the engine bay, so any water should run off, not sure why there is a hole in this position?

The other hole you circled in yellow, Pawel says it's a good idea to plug, as it leads to a box section, and then to the wheel well, where the drains may be blocked

Apologies, not sure where that link came from, luckily Gary has provided the correct link
« Last Edit: December 16, 2022, 20:47:37 by BobH »
February 1965 230SL Automatic
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GM

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Re: Engine bay drain holes
« Reply #2 on: December 16, 2022, 20:27:57 »
Here it is as an attachment
Gary
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mauro12

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Re: Engine bay drain holes
« Reply #3 on: December 17, 2022, 15:55:26 »
This picture can get you confused because is for British cars . Don't you have the same drain hole near the wiper motor ?
Mauro Pisani
250sl 1967 5speed zf manual

BobH

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Re: Engine bay drain holes
« Reply #4 on: December 17, 2022, 16:09:55 »
On my RHD car there is a plugged hole right next to the wiper motor, as i said the cowl that the motor sits in slopes down into the engine, so i can't see that water would collect there, but LHD cars may be different.  Consensus of opinion is that this hole should be plugged
« Last Edit: December 17, 2022, 16:17:56 by BobH »
February 1965 230SL Automatic
UK delivered RHD
Papyrus white, blue hard top & hub caps
Blue soft top
Blue leather

Pinder

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Re: Engine bay drain holes
« Reply #5 on: December 17, 2022, 17:34:22 »
I can confirm the the hole below the wiper motor should have a rubber plug. it will leak into the interior if it gets water there. so plug it up.
1970 280 SL Light Ivory DB 670. 4 Speed manual shift no AC Limited Slip Diff.

mauro12

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Re: Engine bay drain holes
« Reply #6 on: April 13, 2023, 21:18:55 »
How about the drain hole under the brake booster ? Should be plugged ?
Mauro Pisani
250sl 1967 5speed zf manual

Pinder

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Re: Engine bay drain holes
« Reply #7 on: April 15, 2023, 16:05:42 »
On my car directly under the brake boster there is a drain hole between where two sheet metals are welded. it drains to the ground in the wheel well.
1970 280 SL Light Ivory DB 670. 4 Speed manual shift no AC Limited Slip Diff.

mauro12

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Re: Engine bay drain holes
« Reply #8 on: April 15, 2023, 22:23:08 »
So is good idea to leave it free ? No plug ?
Mauro Pisani
250sl 1967 5speed zf manual