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Garage => Interiors & Exteriors => Topic started by: Rimas on 21 May 2013, 02:25 AM

Title: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: Rimas on 21 May 2013, 02:25 AM
Hi all,

well I've been learning the w116 ropes slowly and steadily of late. Some of you may know that I have found the typical 116 wet carpets recently and have started hunting for the problem. Here is what I dug up on Sunday.

My silly error was that everyone speaks about the common rust spot as being under the fuse box. My car is an Aus RHD car and I didn't think that most of the advice I was reading was coming from Europe/USA cars.  ::) :P The spot under my fusebox is super clean!  ;D

Having the car up on the jacks for the suspension work I got my first clue:

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2050_zps5f0830db.jpg)

HMMM, what's going on in here....

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2053_zps3afde8d6.jpg)

Ah, I see! Bear in mind the size of the hole was made worse because I really chipped away with a screwdriver and vacuumed the area out hard after I found it.

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2052_zps54d4a9dc.jpg)

Got some miracle paint and rust converter during the week. Ideally I would love to cut this out and start with fresh metal but to be honest my budget doesn't allow for that.

Will anybody hold it against me if I fix this with fibreglass and miracle paint?  :-\
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: TJ 450 on 21 May 2013, 02:31 AM
Yep, that's a standard rust spot on RHD cars.

One has to be very lucky not to have a hole there.

Tim
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: ptashek on 21 May 2013, 05:10 AM
Quote from: Rimas on 21 May 2013, 02:25 AM
Will anybody hold it against me if I fix this with fibreglass and miracle paint?  :-\

I won't, because that's similar to how I have fixed it for now, even though the hole in my car was nowhere near this size.
Once the body is properly restored I will be encapsulating this very area with epoxy anyway, just because it's a never-ending rot story in there.

In the meantime, keep it nice and clean, and make sure the drain hole is passable.
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: oversize on 21 May 2013, 07:14 PM
Unfortunately this is very common and getting access to fix it is problematic.  I'd even suggest it's the reason many cars end up being scrapped!  All but the very dedicated take the time to get it fixed.  The front guards are quite hard to remove because they're glued in place and the bonnet and dash need to be removed if you're welding otherwise you risk a nasty fire.

But get it fixed and you'll have a great foundation to enjoy.  After years of leaking you'll probably have a dry interior, rid the car of horrible smells and it'll be worth investing in a new set of carpets plus anything else to make the interior even more comfortable.
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: Rimas on 21 May 2013, 09:27 PM
Thanks Ptashek,
I'll make sure to be thorough in there to avoid these problems spreading.

Oversize I did think about taking the panels off, thanks for the forewarning about the glue! I'm probably going to take your advice and get some new modern insulation, (dynamat maybe? hopefully something that I can mould into shape with heat or something similar?) and then see how bad my carpets are.

Looking forward to tackling this on the weekend. I'll feel a lot better once it's all sealed.

Man it's frustrating how people have no idea to clean their cars in these areas over the years/they just don't care.

Not to call myself a hero or anything (lol) but at least this 116 has been plucked from certain wrecking.
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: oversize on 22 May 2013, 02:33 AM
I'd remove the engine bay insulation in the corners as it seems to be part of the problem.  Make sure the corner drain isn't blocked and if you don't have one then drill a hole (there's a couple of threads on this subject).  Protect the edges of any hole you drill with a rust preventer and paint.  Remove the glovebox to improve access from the inside.  Disconnect the bonnet cable at the latch end and pull it into the interior of the car.

Cut out anything that's rusted, removing all the daggy bits.  A Dremel might allow you to get into the tight areas without removing many parts.  Taking the bonnet and springs off might help and it's not that hard if you have someone to help.  Paint the exposed steel with an anti-rust agent to prevent it coming back.  Then I'd buy an oversize piece of sheet steel and bend and hammer it into shape (sounds easy doesn't it?!).  Drill and cut a hole for a new cable grommet.  Once happy with the new panel's shape and fit (test-fit lots) I'd paint it up nicely (both sides).  Then I'd GLUE IT INTO PLACE.  I'm not sure what's the best adhesive to use, but I'm sure there's something out there to suit.  Make sure all the edges are sealed and water tight.  You could then give it all a final coat of paint.  Put it all back together and you're done.  Keep it clean and dry and it should never happen again.

This process avoids the dramas of welding and should be far neater than fiberglass.  If you're not confident in metal working, take the car to an expert to make up the repair patch ONLY.  Doing the rest yourself should reduce the cost substantially.
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: Rimas on 22 May 2013, 05:04 AM
Thanks Oversize!

Great tutorial. I do however think that I'll wing it with some fibreglass for now. I think I'll cut a grommet hole the size of the hood release cable housing and then carefully work up the fibreglass to that. I'll see how I go.

I have a tin of miracle paint and a tube of rust treatment so I will lather the floors, firewall and rust hole in it.

Do you think gluing a piece of metal back in there could invite future rust when the glue perishes?
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: oversize on 22 May 2013, 04:05 PM
If all the metal edges are correctly treated and sealed the rust shouldn't come back.  The only problem I can see with the process I mentioned is that after cutting away all the rust, there may be nothing left to glue to, or provide a sufficient seal.  If water's able to get in-between the old steel and the repair patch then the rust process will start all over again
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: oversize on 22 May 2013, 04:07 PM
BTW do you have any pix from the inside?
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: Rimas on 22 May 2013, 04:12 PM
Hey mate,

yeah I'll get in and get a few good pics tonight. I was intending to get in there Friday morning before work to 'soak' the area in the rust treatment product I have. Apparently the stuff dries and you have to wipe of a residue that forms after the chemical reaction.

Cheers for following up on this thread, it helps me a lot!
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: oversize on 22 May 2013, 04:31 PM
I'd highly recommend trimming off the badly rusted areas first, because the rough, larger surface area means rust has a better chance of staying untreated and continuing to eat away at your lovely car!   :o
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: ZCarFan on 22 May 2013, 07:42 PM
One of my former 300SDs had a hole big enough to get you hand through there.  Was wondering why my leg was getting wet and cold. :)

My current 280 SE is rusted here too, but only a small amount.  Right now I have the cable and grommet out along with the carpet, insulation and drains.  Need to seal it up soon.

Don't get too discouraged there Rimas.  Just work on the items one at a time.  You need to take a long term approach and realize that after a year or two it will stabilize and you will drive more, wrench less.

Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: marku on 23 May 2013, 10:37 AM
Made me go and look at the 450. No hole!! but it has rusted out behind the ignition module. I have seen others with this problem.
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: Rimas on 26 May 2013, 03:48 AM
Thanks for the positive encouragement Zcar, I've started to feel better now that I've done some work.

Here are some pics of what it did to my floor:

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2102_zps622785bf.jpg)

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2105_zps354e6566.jpg)

I also decided to investigate why this rust had appeared on this side of the car too. The pic looks worse because I have hacked away at the rust a bit already and I treated it.

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2127_zps61f13fb5.jpg)

It was really hard to find how water could get through into this cavity, but I found that it was probably through the grommet near the ECU. I think it goes to the vacuum tank that sits in there (grey hose). This grommet sits right in the path of my waterfall caused by the main rust hole. I played around with a few ways to funnel some rust converter into this area through the grommet until it leaked out where the rust was. Glad I did this because hopefully it will buy a bit of time until I get the panels touched up.

I also decided to check in the fresh air vent and found an interesting sign of buildup and corrosion that everyone should take care with. It's obviously one that is hard to access but I'm glad I did. Will be including this area in my rust treatment/miracle painting.

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2122_zps3735290f.jpg)
(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2121_zps29d4411b.jpg)

And finally, after much scrubbing, vacuuming, treating with a rust converter and a fish oil blend I got the first delicate layer or fibreglass on with a good layer of Miracle Paint.

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2123_zps244af9ee.jpg)

It may look a little rusty coloured in the area, but this was the fish oil blend spray that I was getting into every nook and cranny.

Forgive if the fibreglassing looks a tad dodgy at this stage, it was just really difficult and important to span across the area. This first layer is mainly to create a surface to work with and refine next weekend. The stuff should be hard as a rock because it was already starting to set when I applied it.

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2124_zpscb1474ed.jpg)

It was surprisingly good to work with, I decided that bonnet/hood release grommet hole was too difficult to fashion so I will just seal this cable with the fibreglass and maybe a silicone next time I work on it.

Anyway that's what has kept me busy this weekend, I hope you all enjoyed yours!

Rimas
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: w116john on 13 June 2013, 06:23 AM
hi
I'm just after finding something just like that in mine , just under the bonnet release gromet.

I am just going to do what you did to repair it and hopfully keep it dry, did you repair the drain hole?

and if you did any tips ?  my car is lhd and the fuse box is next to that spot and any water build up goes under it,

I'll patch as best i can and later on in the year i have the rust sorted professionally

best of luck with your repairs

john
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: littlefin on 13 June 2013, 07:36 AM
Quote from: TJ 450 on 21 May 2013, 02:31 AM
Yep, that's a standard rust spot on RHD cars.

One has to be very lucky not to have a hole there.

Tim

I need to take a good look in that spot next time I'm under the bonnet  :o
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: oversize on 13 June 2013, 04:44 PM
Yep I think it's the major cause of death in most W116s.  I think many drains were blocked with sealant when they left the factory
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: TJ 450 on 13 June 2013, 10:58 PM
On all the cars I've seen, none of those drains have been clear, even though I know they are there. On rust free cars, it wouldn't hurt to make a new drain.

Tim
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: Rimas on 14 June 2013, 07:46 PM
Quote from: w116john on 13 June 2013, 06:23 AM
hi
I'm just after finding something just like that in mine , just under the bonnet release gromet.

I am just going to do what you did to repair it and hopfully keep it dry, did you repair the drain hole?

and if you did any tips ?  my car is lhd and the fuse box is next to that spot and any water build up goes under it,

I'll patch as best i can and later on in the year i have the rust sorted professionally

best of luck with your repairs

john

Hi John how bad is yours? Can we see a picture?

I found that I had to pull out the sound deadening in the floor wells, cut away the firewall insulation and 'dig' around underneath in the wheel arch to discover the true extents of the rust problem. I found that water was not only coming in through the gaping rust hole, it also created a smaller one just below it right behind the heater box. This was tricky to get to.

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2106_zps81553ce9.jpg)

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2130_zps66876505.jpg)

the first thing I did was vacuum the areas and pick away at the old rust with a screwdriver, wire brush and whatever else.

Then I applied these following products.

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2219_zpsd3ef3dd2.jpg)

The first one on the left is a tar/fishoil blend that works really well in sealing rusted areas that you can't reach. I found it useful to get it up under the dash where the firewall rust had started. Also I've used this product in my doors. Initially I was going to make the rust kill blend with diesel, fish oil and thinners but this stuff did the job.

Any exposed rust I then treated with a rust converter. The next step was to use the 'Miracle Paint' stuff, it's like a really hard resin that binds to rust and moisture helps it set. This is what I was able to do the fibre glassing with. The KBS stuff underneath is the same, just a cheaper Ausssie alternative brand. I'm going to do my whole floors and firewall again with this stuff just to be sure.

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2188_zps58137d8b.jpg)

I then finished over it with white enamel paint to try and seal it up.

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2190_zpsa4d3c3bd.jpg)

Here is the same process done except with the floor/firewall.

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2192_zps3cb80293.jpg)

Inside the wheel arch and under the floor I have sprayed under-body tar to make sure that the rust is sealed from BOTH sides.

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2222_zps6192b2d1.jpg)

Today I will be buidling up a silicone seal in lieu of the grommet, sealing it with the enamel paint and lathering the WHOLE of my floor in that rust seal stuff.

Tomorrow I will test for water leaks, drill a drain hole through the fibre glass and start putting this poor W116 back together and lay the dynamat to replace the old mouldy sound deadening (thanks Oversize for the product tip). Dynamat is expensive so I bought 4 sheets. One sheet fits PERFECTLY on the floor. Happy times. The other I have to do to the drivers side and I'll get up under the dash to replace the firewall insulation that I cut away.

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2218_zps6490ef1a.jpg)

Hope that helps!

PS, my work may look crude, but it's way more important to me to get this thing sealed and treated so that I can enjoy using the car again. This car is my go car, not my show car. I would love to delicately cut and replace rust with new welded metal but my budget/vision for this car doesn't allow me that luxury.

At this stage I'd prefer a mechanically perfect car with an 'honest' body/paintwork that I can enjoy rather than an immaculate car that I'm scared to park at shopping centres.

Rimas
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: TJ 450 on 15 June 2013, 03:12 AM
Nice work for sure!

Yes, the main thing is to stop the water getting in there and making the problem worse.

Tim
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: w116john on 15 June 2013, 12:30 PM
hi Rimas

nice job I spent the last few days doing the same job, but i had put in some sealer earlier to see if that would stop it so i had to take that all out again, and then sand treat and fill both sides.

before i filled it i inserted a piece of tubing to recreate a drain hole , its about 6 inches too long , i will cut it at some stage and so far so good its working,  rain is never too far away so its easy to test.

next the boot, the rear light is letting in lots of water.

new to photo bucket so see if this works

ok so pics in next post
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: w116john on 15 June 2013, 12:39 PM
(http://i1364.photobucket.com/albums/r735/w116john/IMG_1135_zpsc6ed45e6.jpg) (http://s1364.photobucket.com/user/w116john/media/IMG_1135_zpsc6ed45e6.jpg.html)
(http://i1364.photobucket.com/albums/r735/w116john/IMG_1132_zps51fd1240.jpg)[/URL[URL=http://s1364.photobucket.com/user/w116john/media/IMG_1120_zpsb674d31b.jpg.html](http://i1364.photobucket.com/albums/r735/w116john/IMG_1120_zpsb674d31b.jpg)[/URL[URL=http://s1364.photobucket.com/user/w116john/media/IMG_1118_zps4b68e900.jpg.html](http://i1364.photobucket.com/albums/r735/w116john/IMG_1118_zps4b68e900.jpg) (http://s1364.photobucket.com/user/w116john/media/IMG_1132_zps51fd1240.jpg.html)
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: w116john on 15 June 2013, 12:51 PM
hi

three posts where one would do, pics in last post

pic 1 is new drain tube, a little long but working
pic 2 is repair area beneath bonnet release
pic 3 original hole from inside

pics in this post

drain hole top and bottom

(http://i1364.photobucket.com/albums/r735/w116john/IMG_1118_zps4b68e900.jpg) (http://s1364.photobucket.com/user/w116john/media/IMG_1118_zps4b68e900.jpg.html)

(http://i1364.photobucket.com/albums/r735/w116john/IMG_1125_zps57406759.jpg) (http://s1364.photobucket.com/user/w116john/media/IMG_1125_zps57406759.jpg.html)

Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: oversize on 15 June 2013, 04:25 PM
Good to see these cars getting the attention they deserve!  Unfortunately many owners aren't aware they have blocked drains that're causing their cars to rust to the point where water comes inside.  The first time it gets noticed is when the carpets are wet and by then it's already a big problem to fix.

BTW you guys know that the inner wheel arches were originally painted in the body colour right?  With all the dirt they can look black, but they're not meant to be.....
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: Rimas on 15 June 2013, 05:53 PM
Quote from: oversize on 15 June 2013, 04:25 PM
BTW you guys know that the inner wheel arches were originally painted in the body colour right?  With all the dirt they can look black, but they're not meant to be.....
:o :o :o

Wow.

Hey John, yours isn't looking as bad as mine was however that hole looks like the rust could extend a fair bit further underneath the surface.

Guys I'm getting confused where the drain hole is actually supposed to be. Mine seemed to have no evidence of a drain hole at all?!

I assumed there wasn't one and was going to make one here so that it drains into the wheel arch:
(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2188b_zps50b80888.jpg)
I was thinking I'll put a pipe in so that it doesn't simply cascade over the wheelarch.

Cheers

Rimas
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: oversize on 15 June 2013, 06:53 PM
The hole should be at the lowest point to drain all the water away and keep it dry.  If you remove the deadener from the passenger side of the inner wheel arch, you should find a separation between the firewall and the wheel arch panels.  Probably the best way to do that would be bead blasting, but a scraper would do.  This is a very late W116 and I'm not sure if they're all the same or whether MB made a design change after identifying the problem.  Can you see the light?

(http://i1044.photobucket.com/albums/b448/Sixpointnine/Green%20Lantern/CIMG7457_zpsfb8ea40d.jpg) (http://s1044.photobucket.com/user/Sixpointnine/media/Green%20Lantern/CIMG7457_zpsfb8ea40d.jpg.html)

(http://i1044.photobucket.com/albums/b448/Sixpointnine/Green%20Lantern/CIMG7459_zps77821fd1.jpg) (http://s1044.photobucket.com/user/Sixpointnine/media/Green%20Lantern/CIMG7459_zps77821fd1.jpg.html)

(http://i1044.photobucket.com/albums/b448/Sixpointnine/Green%20Lantern/CIMG7463_zps03db87ad.jpg) (http://s1044.photobucket.com/user/Sixpointnine/media/Green%20Lantern/CIMG7463_zps03db87ad.jpg.html)
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: oversize on 15 June 2013, 06:55 PM
Aussie driver's side:

(http://i1044.photobucket.com/albums/b448/Sixpointnine/Green%20Lantern/CIMG7450_zpsd70f59f1.jpg) (http://s1044.photobucket.com/user/Sixpointnine/media/Green%20Lantern/CIMG7450_zpsd70f59f1.jpg.html)

(http://i1044.photobucket.com/albums/b448/Sixpointnine/Green%20Lantern/CIMG7453_zpsf3f91d64.jpg) (http://s1044.photobucket.com/user/Sixpointnine/media/Green%20Lantern/CIMG7453_zpsf3f91d64.jpg.html)
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: oversize on 15 June 2013, 07:00 PM
Note that I can't see the opening for the hole on the RHS near the fusebox and it's obviously been blocked for years and I think it's rusted through.....

(http://i1044.photobucket.com/albums/b448/Sixpointnine/Green%20Lantern/CIMG7449_zps3817a803.jpg) (http://s1044.photobucket.com/user/Sixpointnine/media/Green%20Lantern/CIMG7449_zps3817a803.jpg.html)

(http://i1044.photobucket.com/albums/b448/Sixpointnine/Green%20Lantern/CIMG7448_zps8e9c5ca5.jpg) (http://s1044.photobucket.com/user/Sixpointnine/media/Green%20Lantern/CIMG7448_zps8e9c5ca5.jpg.html)

(http://i1044.photobucket.com/albums/b448/Sixpointnine/Green%20Lantern/CIMG7447_zps150cdefa.jpg) (http://s1044.photobucket.com/user/Sixpointnine/media/Green%20Lantern/CIMG7447_zps150cdefa.jpg.html)
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: oversize on 15 June 2013, 07:01 PM
I might try to force through a screwdriver from underneath and see where it comes out up top.....  I'd say it'll be to the right of the fusebox
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: oversize on 15 June 2013, 07:09 PM
Looks like Rimas car is the same looking back at the first pic.  Obviously the drain was totally blocked and the insulation kept it all damp.....
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: w116john on 16 June 2013, 01:08 AM
hi
my fix is temp i will have to get it welded later in the year , it is a really awkward spot to work at especially lhd with the fuse box so close.
hopefully I'm dry for a while, but my floor matting is shot.

oversize i used a coat hanger to find the drain hole pushing up from below it looked just as yours does, then tried to scrap out as much as i could

rimas i was going to drill a new hole but firstly i put in a small tube and some sealant which did not work, so i then dug it all out and put in a larger tube from a garden hose, which looks as if its large enough to take the water.

drilling a new hole is a good idea find the lowest point, i also think putting in a tube is a good idea, you could fashion it from fibreglass?

now to fix the swimming pool in the boot.
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: Rimas on 16 June 2013, 04:56 AM
Quote from: oversize on 15 June 2013, 07:00 PM
Note that I can't see the opening for the hole on the RHS near the fusebox and it's obviously been blocked for years and I think it's rusted through.....

Thanks for the pics, I'll definitely have to check that side more thoroughly too. Yeah I had no evidence of a drain on mine, it was mostly just rust.

The strange thing was that it had also rusted a secondary hole into the firewall just underneath which would have been the end of the car had I not found it. I finished the work today, did a water leak test and no signs of leakage. I did however find a small amount later in the day in the rear of the car. I think my windscreen rubbers would have caused that because I gave them a big soak. So that was a bit of a let down.

I did however get to drive the car again for the first time in about 4 weeks, man was the lack of road noise great with the dynamat and, well, I guess the lack of a big hole in my car! By the way highly recommend dynamat for ease of use. It was great to work with.

Just hope like crazy that I found and properly treated all the rust, it would be a nightmare to pull up all those sticky sheets.

Quote from: w116john on 16 June 2013, 01:08 AM

rimas i was going to drill a new hole but firstly i put in a small tube and some sealant which did not work, so i then dug it all out and put in a larger tube from a garden hose, which looks as if its large enough to take the water.

drilling a new hole is a good idea find the lowest point, i also think putting in a tube is a good idea, you could fashion it from fibreglass?

now to fix the swimming pool in the boot.

Good idea, I was thinking about fitting a pipe with a flange end. I could drill the exact size hole and it would just sit in. Would have to make sure the flange is as flush as possible to the surrounding surface, maybe building it up with fibre glass or just silicone.

I think no matter what, we will make sure that these areas are clean on our cars from now on!

Cheers

Rimas
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: oversize on 19 June 2013, 02:10 AM
I just checked one of my cars (Moby) that appeared to have no rust in this area.  Despite it being an early car, the panels are the same design as the late car (Green Lantern) in the pics here.  I pushed a piece of wire (modified coat hanger) up through the opening from underneath but it wasn't coming through at the top.  So I peeled off the firewall pad around the bonnet cable grommet.  It appears the pads were installed first, followed by the grommet, so the pad is sometimes difficult to peel back.  What I found was that the pad was blocking the hole and as a result IT HAD RUSTED THROUGH THE FIREWALL!   >:( >:( :( :( :'( :'(  The drain holes were only small and it doesn't take much for them to block up.  Compare the size of these holes to the drains for the plenum below the windscreen and you'll see what I mean.

So the moral of the story is that if your car still has the firewall pad in place, it's likely to have rusted out the firewall and allow water into the car.....  If you're installing a new pad; CUT OFF THE EXTREME ENDS BY AT LEAST 100mm or risk a rust disaster later.  Not happy Jan....
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: oversize on 19 June 2013, 02:14 AM
Oh and if you intended to fix this problem professionally with a steel replacement panel, I reckon it'd be best to pull out the whole dashboard and attack it from the inside.....
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: Rimas on 20 June 2013, 02:57 AM
Oh no!

Pics?

Are you talking about the 'pad' on the engine bay side? This is what I peeled back to discover my problems..

Taking the dash out for that is highly recommended, I chose the "paint brush covered in rust seal, splatter all behind the dash blindly" approach. I hope I got it all!

What will you do about this one?
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: oversize on 20 June 2013, 04:14 AM
Moby is a low priority as he needs lots of work.  But the dash has already been pulled by one of the POs and it wasn't even put back completely so ripping it out again shouldn't be too hard....  I'm just thinking how I'd redesign the panels and drain area so it'll never happen again
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: TJ 450 on 20 June 2013, 07:21 AM
Also, the contact adhesive used probably holds moisture in behind there, causing further problems. The rust appears to spread out in a radius, suggesting to me that the adhesive acts as a wick.

Removing the dash opens up a whole can of worms, one in particular being not destroying it in the process.

One needs to be prepared for the left hand corner of the dash to be damaged during removal, if it is brittle.

Tim
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: oversize on 20 June 2013, 04:09 PM
If you dash hasn't been replaced recently, it's probably ready to crack too (if it hasn't already).  You'd have to plan for a new one, or recovering it during the job.

I'm starting to think the whole insulating pad should be removed, as I'm worried about rust and not concerned about a bit of extra engine noise....  But I'm sure it'd be an engine out process if you wanna do it properly
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: TJ 450 on 20 June 2013, 09:02 PM
Yes, I don't like anything that hides sheet metal like that. The only problem is that it almost certainly doesn't look original without it. Mind you, it could be painted black. 8)

You wouldn't need to remove the engine, just all the mechanisms and clips attached to the firewall, including the accelerator linkage.

The remaining contact adhesive will be a PITA to remove though.

Tim
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: oversize on 23 June 2013, 05:52 AM
I really don't know why they didn't have the deadener on the inside only....  When repairing this area I'm seriously considering completely redesigning the drains and some of the sheet metal.  Having the inner guard meet the firewall in a downward curve is madness and a natural water trap.  Long term even seam sealer won't stop it from rusting due to the harsh environment
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: oversize on 23 June 2013, 06:00 AM
I'm also thinking there must be a better way to protect the firewall during inner wheel arch duties than just coating it with bitumen deadener....  I'm thinking moulded plastic with deadener on the back to prevent excessive noise and drum
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: Rimas on 24 June 2013, 02:27 AM
I guess as long as moisture or oxygen are removed from the equation, rust won't occur. Bitumen should be fine.

I've found a really good sticky product that dries hard and is a blend of fish oil and tar. Fergusons Knock-Out: http://www.knockout-rust.com.au/information.html

Seems to get into all the hard to reach spots. I did all in my fresh air dam, smelling quite chemically driving to work this morning.  :P
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: ripley on 13 July 2015, 02:59 PM
Hi guys,
could someone send me a MIRACLE PAINT to Lithuania? :) seems like a good stuff.
I could pay extra for helping...
Thanks.
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: gurrier on 28 December 2021, 02:07 PM
Hi. I can't view the pictures. Anyone have an idea what I can do


Quote from: Rimas on 21 May 2013, 02:25 AM
Hi all,

well I've been learning the w116 ropes slowly and steadily of late. Some of you may know that I have found the typical 116 wet carpets recently and have started hunting for the problem. Here is what I dug up on Sunday.

My silly error was that everyone speaks about the common rust spot as being under the fuse box. My car is an Aus RHD car and I didn't think that most of the advice I was reading was coming from Europe/USA cars.  ::) :P The spot under my fusebox is super clean!  ;D

Having the car up on the jacks for the suspension work I got my first clue:

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2050_zps5f0830db.jpg)

HMMM, what's going on in here....

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2053_zps3afde8d6.jpg)

Ah, I see! Bear in mind the size of the hole was made worse because I really chipped away with a screwdriver and vacuumed the area out hard after I found it.

(http://i1306.photobucket.com/albums/s572/rimas280/Photobucket%20Desktop%20-%20Rimos%20MacDaddy/280SE/IMG_2052_zps54d4a9dc.jpg)

Got some miracle paint and rust converter during the week. Ideally I would love to cut this out and start with fresh metal but to be honest my budget doesn't allow for that.

Will anybody hold it against me if I fix this with fibreglass and miracle paint?  :-\
Title: Re: A nasty rust surprise. A huge hole near the bonnet/hood release cable grommet.
Post by: daantjie on 28 December 2021, 02:43 PM
Best start a new thread and post pics of what you are facing.