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Discussion Starter #1 (Edited)
Looking into repairing the top engine cover on the 2.4... I'm missing 2 of the little rubber grommets for the pins on the engine (71747919) these are cheap enough and not too hard to get hold of.

The fun bit is repairing the pin that is supposed to be cast onto the cover itself located on the O/S/F of the engine. It has been snapped off by a 'cautious' previous owner/garage. :irked:

I'm thinking of buying some nylon rod/nylon nut and bolt to repair this. The reason Im choosing nylon is because by the looks of it the cover is also nylon (has the letters PA embossed on the underside, below the part number, which is Polyamide I.E. Nylon) its flexible which is nice because of the vibration of the 5cyl diesel lump.

My question is what would be the best Nylon adhesive/cement to use?
I want it to be permenant, rigid but not brittle, and suitable to use in the engine bay (somewhat heat, vibration and fluid resistant).

as always all suggestions welcomed.
 

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Nylon is notoriously difficult to glue but you could try JB Weld PlasticWeld.
 

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Discussion Starter #3
Nylon is notoriously difficult to glue...
what about a heat process? is it possible to 'weld' nylon successfully? theres still a small 'pod' left of the old pin.
 

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Discussion Starter #4 (Edited)
After a bit of research and without wanting to get into heating techniques or industrial adhesives i think I'm looking at either Loctite - Epoxy Plastic Bonder (which seems to be rather hard to source in the UK) or JB Weld - Plasticweld

Would someone be able to measure the length and width of the pin for me (as mine is missing)?

Edit:- after doing some more research... the above 2 are a little low on their operational temp thresholds of 80*C... i have now decided to go with this... Permabond product. all i need to do now is find a gun
 

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On motorcycles I have quite often had to rebuild or replace plastic pegs that hold bodywork panels and fairings in place. Have to really, given a panel can cost a fortune for the sake of a flimsy broken peg. ABS is easy - plastic welding, epoxy, Plastex, all work fine. But nylon and polythene/polypropylene cannot be plastic welded, and adhesives don't tolerate its 'greasiness' well.

Golf tees come in all sorts of shapes and sizes, you may be able to re-purpose one to form a peg, upside down. IE a small hole through the engine cover and a spring clip washer to hold it in place, cut off the excess 'spike' and cover with a blob of sugru or epoxy putty. Or use a black numberplate bolt through a hole, clamped with a nut underneath, and build up a shaped peg on the threaded part with epoxy putty.

It's strangely enjoyable mending stuff like this...
 

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Discussion Starter #7
I hadn't really entertained a 'loaded' epoxy, its not something i would have immediately thought of to repair a plastic. It's made the short list though, so thanks.

... nylon and polythene/polypropylene cannot be plastic welded, and adhesives don't tolerate its 'greasiness' well... It's strangely enjoyable mending stuff like this...
the glass reinforced varients seem to fair a little better with regards to adhesives, a lot of documents i have found state that it is MUCH easier to get a reliable bond on GR rather than 'pure' forms of Nylon. also the GR adds to the materials strength and heat resistance from what i can make out (i'm 98% sure the engine cover is GR). ive found an application gun for the permabond stuff at a decent price if thats the way i decide to go. My next challenge is to find GR nylon rod in the correct diameter and length once somebody can supply me with measurements for the 2.4 JTDm. i wanted to steer away from drilling the engine cover for obvious reasons, i quickly shut down that idea when i was thinking about what to do about it.

Success seems to be in the prep work numerous places suggest drying out at 60°C for several hours or even overnight. it seems to be advisable to abrade the surface to allow extra mechanical bonding then a degrease with isopropanol. whilst 2 part and premix epoxies are better than cyanocarylates (basically super glue). MS polymers (sikaflex type bonding), Polyurathanes (carbon-fiber and GRP bonding) and Structural Acrylics seem to be favoured. Acrylics seem to have the best of all the desired qualities temp ranges, vibration/heat/fluid resistance, colour choice and cure speed.

Yes it is lots of fun ;)
 

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Discussion Starter #9

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A better excuse than mine: I just hate junking stuff that shouldn't have broken in the first place. Which is why I will be busy with this car forever.
 
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