My door seals are melting!

[SteveUK]

Hi guys,

I have just been down to my '85 M1009 and check things are okay (and scoping out the dodhead conversion). It is stored in a barn which is generally dry.

Just closing the truck door I felt that the door seal - the one on the body - was sticky!
I am talking about the textured moulded plastic/rubber part, not the tubular section rubber that forms the actual seal when the door is closed.

It appears to be 'sweating'- or actually decomposing. I checked the drivers seal, which is off the vehicle and that is also going sticky.

Now this is definitely NOT to do with heat - this is the United Kingdom and while we have not experienced the snow and ice in the US, the beginning of March in the UK is usually cold and wet.

What is causing it and how do I stop it? As far as I can tell the seals are stock, and apart from being dirty at the bottom edge, looked to be in good shape.

I could do without having to replace these seals.

 

[61sleepercab]

I have seen the same thing happen on old rubber parts that either gets dry, cracks and gets brittle or turns to a tar like goo that gets soft. For dry rubber you can try rubber treatments like Armor All over here. There are stuff on EBay as well.

I do not know any treatment for rubber stuff that has turned into goo . This is what natural rubber used to do before vulcanization was invented. Remember the seals may or may not be rubber as a lot of "rubber" stuff today is man made. Our county has a plant that makes synthetic rubber since WWII days. Ozone gas and sunlight also eats rubber. You might try some graphite powder to keep the seal from sticking where you do not want it to.
Remember your truck is approaching 30 years old and the seals just may have given their all. Mark

 

[DieselBob]

Pretty much once rubber and plastic starts to decompose you can’t recompose it. Sounds like new seals are in your future.

 

[3rdaavbn]

Talcum powder will buy you some time. (not corn starch)