A simple oil change nightmare

[Vectrolosys]

Hi all,

Decided to complete a simple oil change on my 300TE, only to have the sump bolt round off!! Anyway, I left it for a few days and looked up online how other people have overcome the problems. Below is a quick youtube video I uploaded with how I resolved the problem on my W124.

Thought I'd share this with you all, as I had it happen to me whilst trying to complete a simple oil change.

http://www.youtube.com/watch?v=ekwpCgVAgFE

Rounded sump bolts are a pain and can seriously hold up an otherwise simple oil change. Don't panic, most of the time, they can be removed easily with some simple tools and minimum fuss.

- Remove any undertrays
- Cover the bolt in a good penetrating lubricant
- Leave to saturate for 20 minutes

- On your return, file the edges of the bolt so they are flat on two sides.
- apply some mole grips, tightly and exert some force.
- The bolt should begin to loosen.

- For severe cases, leave to saturate overnight
- Acquire a blow torch and apply heat to the bolt, then try molegrips.

You'll need.....

- Molegrips
- Penetrating lubricant
- New sump bolt
- Sump bolt washer
- Correct amount of engine oil for your car
- Oil filter
- Patience!

Hope this helps someone in the same situtation, or someone searching in the future.

James

 

[Will]

Top tip:-

When buying the oil filter and sump plug washer for the first time on a new (to you) car, get a new sump plug too.

Chances might be that you don't need it, but best to be prepared. They cost peanuts, and if the old one is slightly damaged you'll be pleased to be able to refit a new one

People often overtighten sump plugs - perhaps because some people don't remember to buy a new crush washer for refitting. The sump is aluminium and the washer is copper, no need to overtighten - I can't recall the torque spec off hand but it's not a lot, 15 or 22Nm or something.

Will

 

[Will]

Last thing - it's good practice if possible to use a proper six-sided socket on the plug and make sure you are square on it. Don't be tempted to try removing it at an angle if access is difficult etc. Open ended or 12-sided sockets won't give you such good purchase if you think it's going to be difficult to remove (!)

 

[Vectrolosys]

I learnt the hard way!! I neglected to use a proper, hex headed socket, even though I have one. I suggested the use of one in the video . Seeing as the sump bolt was a couple of pounds, tops, I'll be changing it each time, in the future.

 

[Ian B Walker]

Whenever I find a sad looking sump plug I go straight to the Erwins and remove it with those. A new sump plug is not expensive to purchase. Another tip. On old and new copper washers, anneal them first before fitting. It makes for a better seal. BTW the torque figure for fastening them up is 25nm.

 

[Will]

I learnt the hard way!! I neglected to use a proper, hex headed socket, even though I have one. I suggested the use of one in the video . Seeing as the sump bolt was a couple of pounds, tops, I'll be changing it each time, in the future.

Honestly, they should last for years - they only get nipped up.

I expect that it was quite worn due to being overtightened/removed carelessly in the past and you got the short straw today.

Just clean the threads and fit a new washer, and if you don't overtighten it, it should last a lifetime

Will

 

[ringway]

There is also the possibility that the previous owner never removed the sump plug and instead sucked out the oil with a Pela-style pump.

This could mean the plug had been in the sump for years.

By the way.. I change my oil by sucking out with a pump.

 

[SilverSaloon]

I changed my oil yesterday on my 124.

my bolt is looking a bit tired and next change i'll be replacing it.

agreed, you need a good socket on the bolt rather than an open ended spanner etc, which will just chew it a bit.