Warning-Diesel Filter cap leak

[chalkyaj]

Hi all, My wife came home in our MY14 2014 3L CRD and there was diesel trail up our driveway.
Checked underneath and there was a pool of diesel under the filter housing. I got her to start it momentarily to identify were it was leaking. It was spraying with some force out of the rear filter cap. I removed the rear filter and replaced the cap from one of my spares. It had a hairline crack around the base of the moulded hex part for the socket.
I have bought Genuine from the states, Ryco, Wesfil and Sakura in the past and only reuse the caps no more than once. I installed a Ryco on the last service and reused a cap as the Ryco don't come with them. As i said i usually fit new caps and occasionally reuse.
I always use a torque wrench also so were not overtightened.
We were lucky it let go just as she got home and not sixty K's away.

[Troutman]

Yeah I'm a big believer of use once on these plastic nuts and buy the Wesfil filters with the caps for peace of mind.

That one of yours could have taken a hit from underneath the vehicle too mate.

[Mudguard]

as they may take a hit while off-road I made a cover plate for mine from 6mm Aluminium

[chalkyaj]

Yep, Hindsight is a wonderfull thing. You could reasonably expect it to be fine for at least one reuse and if the ABS plastic is not that good you could put a new one in and have it fail. Also the oil filter cap is the same plastic and gets screwed on and off every service, mine has been reused 18 times now.
I like the idea of guards and i have the Transfer/case fuel tank etc covered but there is still so much exposed gear underneath you cant protect every thing.
I first though i had hit something but both of us don't recall clunking on anything and i think it would have gouged it. From looking at it it is neatly cracked around the moulding and looks like a flaw. I dont know what brand the cap is it could even be one of the Mopar ones or Wesfil they all are exactly the same only difference is the o/ring colour
Anyway its just a warning to others to be aware of the potential problem.