MKX-420G Front QTR Vent seals

(tony) #1

On the upcoming schedule is replacement of the front NDV seals on my 420G

After consultation over the years, the balance of advice is the NDV seals sold to fit our cars do not fit correctly.

I have been advised by one very expert person the best option is to modify MK2 items

So I obtained them, they are much less costly than the advertised items for 420G,
which is also a bonus

attached is a picture, with the 2 sections I must excise highlight in yellow

the profile matches, and the vertical height is the same
the cut sections will be butt glued with isocyanite

speak now or forever hold your peace

(Andrew Waugh) #2

I’m not sure I would bother gluing them before installation. Once they’re in you can probably open the gap and bond them together then.

I wouldn’t use a hard isocyanate, I’d cut them so they press against each other, then spread them apart and apply some bicycle patch cement. If you end up with a gap, the PU gasketing compounds are pretty good at bonding, they stay flexible, and they’re black.

(tony) #3

good feedback already, cutting but not gluing till final fitment is prudent

cant decide on glue.

Isocyanite is recommended for strong quick bond of “unknown” rubber type, however I would be just as happy with a black glue, so long as I know it will work.

I hope my cuts are sharp enough to be near gap free, but figured any gap could be backfilled with a black silicone or poly

you dont happen to know what sort of rubber the seals are? nitrile, butyl

(Andrew Waugh) #4


Avoid backfilling if at all possible if there is any kind of a lip, it’s bloody hard to do without a huge mess, and nigh to impossible to do invisibly.

Hard to tell what material your seals are, but if I’m not mistaken you’re removing a small section, so you’ve got a piece to try. If you clean really well you can put a tire patch on a CV boot and it will stay (I did one about a year ago as a temporary measure and it’s still holding).

To get a clean cut, you can make a miter guillotine with a couple of bits of wood, some Al angle, a fresh Olfa blade, and a screw through the hole in the blade. Mark your cut line with a pastel marker (comes off easily) and scriber, Put the rubber in the freezer overnight, and chop it while cold.

(tony) #5

Thx Andrew great advice, its been waiting a while now, so I wont rush it

Feedback welcome here for owners needing to do this job

Has anyone successfully fitted a MKX-420G front NDV seal ?

Over the years I have communicated with several owners who tried various sources with no joy, yet I see well restored cars?

George C, a reknown poster and 420G owner stated many years ago he had fitted SNG items, and had no issues

(Mike Eck) #6

I use this tool to accurately cut o-rings
and other such material:

Mike Eck

New Jersey, USA

'51 XK120 OTS, '62 3.8 MK2 MOD, '72 SIII E-Type 2+2

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(tony) #7

rang the fellow that did my rear windscreen seal, been doing auto glass 30yrs

He advised Loctite 406 is the best product for gluing rubber seals

They even advertise it as being suitable for “emergency o-ring repair”

on its way from Singapore for $2.39

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(Micah Wellman) #8

I’m not sure what seals are being sold now. Ten years ago, I replaced mine with a reproduction set. They had one flaw, a thin lip was missing. It was the crucial piece that made the seal. Fitment in the corners could have been better. I wrapped sections of the vent in vinyl tape. I then used a urethane window sealant to fill the gaps. It did not stick to the tape. Let it set for a week, pry it apart and do another section. This gave me a custom seal around the vent glass and its frame. They seem to be water tight and I don’t get wind noise.


(tony) #9

So I removed the front vent glass and seal from the spare door shown pictured in the 1st post

made a partial test fitting of the loose seal & can report that the “profile” appears correct
it has a foot that fits tightly within a chrome lip.
Not easy to install, and no glue will be needed to hold it in place

It will slightly complicate my installation, in that there will be no room for error in cutting
however, if I get that right, pretty confident it will look and be as near to factory as possible

much better than the present ruined thing

my informant, owning at least 6 MKX over many years, reported similar situation to yours Micah

Just waiting on my special glue to arrive now!

(Paul Wigton) #10

I used the same technique to repair my next-to-impossible-to-get NDV seals, on my Rover.

(tony) #11

So I thought I might take out the QTR vent window to clean it up, (even though the glue hasnt arrived yet)

The 1st pic is a spare frame I have, and the QTR vent frame is retained by a collar with a roll pin

with the frame out, this is easy enough to punch out, but with the frame still in the door, access to the pin is restricted.

presumbaly there is no alternative but to punch the pin out from the inside of the door & somehow trap it from dropping down into the door ?

edit; answer is yes…I eased a small magnet up behind to stop the pin falling down

(tony) #12

MK2 seal modified and successfully installed…comments later


Even though the job turned out very well using MK2 seals from David Manners Part num
BD17048-9 for 15GBP each,

they also do advertise the MKX set as available BD17459/60

at 85GBP for the pair, we would like a report on whether they do fit?, perhaps they are perfect

at any rate, I am ~98% pleased with the job, the cuts are virtually invisible

I had a surprise issue with the top corner, think this can probably be rectified by cutting in a slightly different spot, will see on the PS side.

cutting must be done in situ, not freezer.

at the base, there is a hole the window post goes thru…looks like a cut in my pic, but that bit is perfect, the post must go thru that hole, and the seal is formed around it

(The Jag Man) #13

Nice work and thanks for the pictures


(Robin O'Connor) #14

Tony, just a tip, when you upload the pictures if you space between the uploads it give the pictures a gap between when they post, makes it a little bit easier to digest, also you can then add text to each photo if required.
Just make sure that you include the ! At the stat of the link :slight_smile: saves you going back into the post (ask me how I know)

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(Paul) #15

Perfect timing!

I have just discovered why the wood veneer on the passenger side is a little worn in a particular area - the window seal leaks.

I was wondering why there was a spare new seal in the boot of the car when I bought it. :smile:

No idea if it is an MK10/420G one or a Mk2. I’ll measure tomorrow and see if I can emulate the tricks here to make it fit.

Cheers for all the pointers!

(tony) #16

dont think many people know about the MK2 trick, although I do see seal advertised to fit both!

the MKX horizontal section is ~1" shorter, so its easy to tell, by offering it up.

I will post a pic later showing some important minor details about where I cut

directly below the qtr vent is a vinyl covered panel on the front top inner door shut.
when I removed it, the door is rusted underneath…I advise you to check this area.

its a common rust area, hard to detect, (and hard to fix)

(Paul) #17

I took the wood cappings off the door and can see the lock nut. As mine are 420G rubbers I’ll attempt to remove the window and fit the rubber without cutting it.

I guess I’ll need lots of vaseline and a tub of hot water to make it slide in easily :wink:


(Paul) #18

Right, that did not go very well…

I undid the lock nut and managed not to lose it in the door, only to lose the second one as I was concentrating on not losing the washer and spring. It is a standard 8mm nut, so I will find another one.

BUT, then I hit a snag. The pin is connected to a thick washer/ring that is secured with what looks like two grub screws. They are round and have a small hole in the top, but it is so small I cannot see if it is a hex opening or not, and my smallest allan key is way too big. I tried unscrewing with some pliers, but that didn’t work.

Any ideas?


(tony) #19

bro, you have not been paying attention ! :grinning:

go back to my post of ~14days ago, this issue is covered

it is a roll pin…you will need to knock it out front to back…the right size punch is needed,
de-point a nail if you dont have one

it is possible to carefully knock the pin back till the collar is free, but i strongly advise either a magnet, or assistant to hold it with curved needle nose pliers.

any item that drops into the door cannot usually be recovered.

(Paul) #20

Thank you.

Sorry, so many issues and so many questions… I really appreciate your patience!