Removing threaded screws from undertray

[JimClark49]

Hi all,

I need to remove the undertray from my car to change a hose. Their are three screws with threaded heads. What is the simplest way to remove them?

I have already tried putting a rubber band and duct tape on screw to fill the space, but they still would not budge.

[Pie with sauce]

Screwdriver?

[CAPP0]

Can you elaborate, or provide pics? I'm not able to visualise what you mean when you say "threaded heads"?

Most undertrays I have encountered are held on by screws which go into spire clips, or similar. Or there may be Dzus fasteners. Have you tried gripping the edge with mole grips?

[JimClark49]

I am using a phillips screwdriver!

By threaded I mean that they have a phillips head which no longer has the cross as the innards of the screw head has been sheared off. They are very rusty.

The car is a Mk3 Mondeo ST.

They are too rusty and stiff for mole grips to work...i did try.

[Pie with sauce]

CAPP0 said:

Have you tried gripping the edge with mole grips?

^^^ Listen to this man.

[Sensibleboy]

I'd buy some new screws before you remove the old ones.

[RichB]

JimClark49 said:

Their are three screws with threaded heads.

Threaded? You just mean the heads are knackered! Just drill them off and replace with new screws and fixings when you replace the tray.

[CAPP0]

Tap them hard with a hammer to try and break any rust grip, then you are going to have to persevere with the mole grips.

If you really can't get them with that, I can only think that you are going to have to grind the heads off. Bear in mind that you will then need to get the whole clip/screw off once the tray is out of the way (shouldn't be too difficult, you should be able to flick them off with a screwdriver, or cold chisel if they are really persistent) but you'll then have to replace them, and possibly put a penny washer under the new screw heads depending on whether you damage the undertray in the process.

Spire clips readily available on eBay but I *think* Halfords also do a box kit.

[JimClark49]

Problem is the car is lowered and I dont have a ramp. Its hard to get a hammer or a drill underneath the car with limited space.

Mole grips didnt appear to work....I was wondering if their are knackered head screw extractor thingys I can buy?

[dickbastardly]

Hope this helps

http://www.screwfix.com/p/screw-extractor-5-piece-...

They also have bolt removers.
Cheers
Andy

[robinessex]

dickbdly said:

Hope this helps

http://www.screwfix.com/p/screw-extractor-5-piece-...

They also have bolt removers.
Cheers
Andy

Won't work. These will:-

http://www.toolstation.com/shop/p38732?utm_source=...


And then replace with stainless steel. Available in Halfords super stores.