Page 1 of 1

Mk1 Protecting them rear quarters

Posted: Tue Dec 25, 2012 1:52 pm
by flea
After recently cutting out the tin worm from the rear quarters & welding in some new metal i had time to have a good look of how these cars were put together in this area.
I noticed that there is no way you can treat the part of the inner rear quarter that has this rusting problem so i got to thinking how we can cure this or at least help to protect it more.

Capture.JPG
Capture.JPG (34.85 KiB) Viewed 2771 times



First off i noticed that by removing the plug under the wheel arch & getting the wax oil probe in there does NOT get to the problem area no matter how hard you try. I had a go while it was in bits. Its not even on the right side of the inner frame where the problem lies.

So here goes.

I have put a white line inside the arch so you can see where the metal plate goes & the existing hole. As you can see its on the wrong side of the plate. The rust is a problem on the left of the line & the damn hole is on the right.

IMG_5224.JPG
IMG_5224.JPG (44.33 KiB) Viewed 2771 times



So you'll need one of these, Yes a simple rubber bung :handgestures-thumbup:

IMG_5225.JPG
IMG_5225.JPG (45.01 KiB) Viewed 2771 times



Then take a drill & drill out a hole (about half way between the white line & the outer sill/wing aslo about the same distance up from the bottom of the sill) that your rubber bung fits.

IMG_5227.JPG
IMG_5227.JPG (51.64 KiB) Viewed 2771 times



Make sure you remove any burs of metal from your hole. If you notice through the hole you can see the bit thats never reached :whistle: Now don't forget to apply a few coats of primer where you have drilled the hole. I done this once it was finished but i made sure there was no wax oil on the bare metal so the paint adhered properly.

IMG_5228.JPG
IMG_5228.JPG (37.25 KiB) Viewed 2771 times



Now take your wax oil probe. It will go all the way to where the front wing meets the sill just to the front of your door. Make sure that you twist the probe just before you remove it from the hole so it gets to the section that you have drilled your hole in :handgestures-thumbup:

IMG_5231.JPG
IMG_5231.JPG (46.83 KiB) Viewed 2771 times



Then all you need to do is fit the rubber bung.

IMG_5234.JPG
IMG_5234.JPG (39.45 KiB) Viewed 2771 times



Job done :wink:

Here's a drawing i done to explain the construction of the rear wing & sill quarter. The red line shows where the inner section meets the wheel arch.

drawing rear wing structure.JPG
drawing rear wing structure.JPG (91.89 KiB) Viewed 2743 times

Re: Mk1 Protecting them rear quarters

Posted: Mon Feb 02, 2015 9:14 pm
by chris32
Photo10.jpg
Photo10.jpg (155.48 KiB) Viewed 2196 times
Just for Interest I found this and a few other pictures some years ago. Someone had cut the whole cross section out of an MX5 in the US. This view is looking straight down. I think it shows where to get the probe. I did it at the time on my 1990 Mk1 but details have faded.

Re: Mk1 Protecting them rear quarters

Posted: Mon Feb 02, 2015 9:49 pm
by flea
Well done :handgestures-thumbup:

Re: Mk1 Protecting them rear quarters

Posted: Tue Feb 03, 2015 9:34 am
by nedski
:text-coolphotos: Well done. I have two sill jobs lined up. oh the joy :handgestures-thumbup:

Re: Mk1 Protecting them rear quarters

Posted: Wed Feb 11, 2015 12:47 pm
by chris32
Hi Flea do you happen to remember what size hole you drilled. The smallest grommets I could find in Halfords were 9mm and I found I needed a 10mm hole in an old piece of steel to get a fit. It seems quite a big hole to drill in my little car! I thought I had done this about 6 years ago with the rest of the car but when I checked, I must have simply used the big existing "grommeted" hole. I do remember at the time that wax oil dripped out the bottom of the horizontal seam, so it went to many places.

Just a thought: I checked the spot welded join between the wing and the wheel arch and found that between the welds in places there was a definite gap. In fact in one place I found that I could get a hypodermic needle all the way through the gap. (No, I am not a user, it's one I use to refill ink cartridges). Taking the opportunity, I have just got three barrel loads of wax-oil in. If this seam is a point of entry for water then the wax-oil might follow the same path and protect the affected part. The gap will be sealed whatever afterwards.

Re: Mk1 Protecting them rear quarters

Posted: Wed Feb 11, 2015 1:21 pm
by flea
I phoned Autolink & they kindly sent the rubbers I asked for. Give them a call & I'm sure they will have smaller ones there? I seam pasted the gap between the arch & the wing as I believe that is where most of the water can get in

Re: Mk1 Protecting them rear quarters

Posted: Sun Mar 01, 2015 4:24 pm
by chris32
Re: sealing the gap between the spot welds round the wheel arch. I bought some edging strip called "clear body guard" it fits perfectly over the join although it's really for door edges

Re: Mk1 Protecting them rear quarters

Posted: Sun Mar 01, 2015 4:31 pm
by flea
Good idea if it keeps the water from getting in :handgestures-thumbup: How about some pictures to see how it looks

Re: Mk1 Protecting them rear quarters

Posted: Sun Mar 01, 2015 5:29 pm
by Mazda Mender
chris32 wrote:Re: sealing the gap between the spot welds round the wheel arch. I bought some edging strip called "clear body guard" it fits perfectly over the join although it's really for door edges


It will not do what you think it will buddy.
M-m