No Sump Gaurd?

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No Sump Gaurd?

Post by SethY » 18 Aug 2005, 22:48

How ‘essential’ is the plastic tray that sits under the engine (the sump guard I suppose)? I ask as I found mine flapping around under the car being held on by just two bolts yesterday. It seems to have cracked around all of the other supporting bolts, so I reoved the last two and took it off completely. Do I need to find another one from a scrappy or will the car be fine without it?

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Post by j_roc » 18 Aug 2005, 22:59

I took the plastic guard tray off the car (on both my Xantia TD and my Mondeo) and it makes no diffrence to the car whatsoever. I think that the manufacturer puts these guards on to protect rubber pipes/exposed sections of subframe/manifold downpipes and cat converters and also to stop us who like to tamper with cars i.e to make it more difficult to get access to components. P.S the technical name for it is the "undertray". Hope this helps - Alex.

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Post by JohnD » 18 Aug 2005, 23:19

I disagree! I took mine of one winter to do an oil change and because I was in a hurry - and because it was b***** cold, didn't bother to put it back on. Because the lower edges of the wing liners weren't held by the sump guard, they flapped about and broke away from the other fasteners. I had to do a repair with bent ali and pop rivets - before refitting the guard.

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Post by j_roc » 18 Aug 2005, 23:34

Is that a Xantia you are talking about? (john). The tray does help though if you are looking for a oil leak. You take off the tray and go "oh, I have a oil leak".

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Post by Kowalski » 19 Aug 2005, 03:20

One of my Xantias has an undertray, the other doesn't, it makes very little difference. The undertray tends to have oil dripping onto it, which gets dirt stuck to it and the whole lot gets heavy and can start to sag, I'm not really a fan of them at all.

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Post by mattpc » 19 Aug 2005, 03:20

mm my last Xantia was missing this and it was the cooked headgasket that killed it not the missing tray.

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Post by j_roc » 19 Aug 2005, 03:27

John's car must have had a loose archliner, as I took the undertray off my Xantia and it has had no negative effect infact, I think it improved the car as it allowed more air to circulate the enginge and exhaust thus cooling it ever so slightley. The problem is the sponge/foam attatched on the Xantia tray (soaks up water/oil/annything) whereas the Mondeo is plain plastic and can be washed in petrol/degreaser when it gets grubby.

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Post by Robin » 19 Aug 2005, 03:37

Permission to be pedantic and geek like?
No, well I am going to be anyway[:D]
The undertray serves three primary functions hence it's fitment.
First, and possibly the least important is that it reduces noise bouncing off the road mainly when stopped.
Second, it reduces the amount of spray and salt laden spray at that from circulating around the engine bay.
Third and most important, it improves the air circulation and aerodynamic of the car at speed.
The front of any car lifts as the speed increases due to the increase in air pressure under the front, hence spoilers etc on 'sports' saloons. This increase in air pressure reduces the natural flow of air through the radiator and can in exceptional circumstances prevent it totally. The undertray separates the positive pressure area under the car from the engine bay and allows the air to flow through the radiators and away via the back of the engine where the air pressure is changing from positive to negative.
I fully concede that the aerodynamic argument is a weak one in the UK with national speed limits at 70 max. However if you think that you are heading into a 40mph headwind travelling at 60 then the aerodynamic effect is that of you doing 100 in still air! On a hot day this can cause premature overheating, just because the undertray is missing. Food for thought perhaps[?]

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Post by Homer » 19 Aug 2005, 12:49

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by SethY</i>

Do I need to find another one from a scrappy or will the car be fine without it?
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
I doubt you'll find one in a scrappy since most Xantias are missing them anyway.
Niether of mine had one and they suffered no ill effects, and they regularly had a more than 100mph "airspeed".[;)]

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Post by SethY » 19 Aug 2005, 13:53

OK, I'll see how it go without it for now then. Thanks people.

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Post by davek-uk » 19 Aug 2005, 13:57

I have the same problem with my undertray - the bolt holes are cracking/split. All I did was to fit very large washers to the bolts and this helps catch the plastic and spread any stress. Once done up tight I never have any problems.
The undertray is a pain at oil change though. With the mileage I do, I do an oilchange every other month. The little flap is fine to drain the oil and it is placed pretty well. You still have to drop the front of the tray to catch the drips from when you remove the oil filter though - if it wasn't at such a stupid angle it wouldn't empty as you undo it!
Out of interest - and I know this is a bit off topic - was the Xantia ever used for rallying? I was wondering about the possibilities of obtaining a metal undertray. And wondering what other underbody protection they may have had. Any ideas?

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Post by adzbaby » 19 Aug 2005, 19:58

Most cars lose their undertrays after a service/work at a garage/maindealer, they remove them and never other to put em back, wastes valuable working minutes!!
The xantia undertray fixings always corrode especially if they haven't been removed for awhile and when they do need to come off, argh its horrible, rusted PITA mess!

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Post by j_roc » 20 Aug 2005, 02:20

Dave - why not have a go of making one up out of a sheet of Galv or Allu? Go to u local scrappies and cut the side out of a Transit/Traffic/400 panel van. They would prob only charge you £10 - £15 for it. Cant be that hard to cut it to shape. If you decide to go ahead and give it a go, let us know to follow suit.