Forums banner
1 - 3 of 3 Posts

Starlight Silver MG TF 135
36 Posts
Discussion Starter · #1 ·
I noticed black dirt in the top of the screen-wash bottle, and already felt that the supply of screen-wash to the screen was feeble, so I decided o tackle the problem.
First, I CAREFULLY removed the plastic shield covering the bottle. 2 plastic covered nuts on the left:

circled in red above
Then one screw near top right above the brake servo:

Two studs right at the bottom of this plastic panel appear to have had nuts similar to those top right, but none fitted on my car, or perhaps penny-pinching at Longbridge decided these were "not necessary".
The panel can now be removed VERY CAREFULLY. Remember this is at least 15 year-old plastic, with much less plasticiser and far more brittle that when it was young!

The wash bottle was then pulled upwards to release from its clip. The pump can be pulled gently away from the bottle, withdrawing the pick-up spout from the hole in the bottle. The pump with it's wires and the feed hose to the screen-wash nozzles can be parked complete on the top of the subframe, whilst the bottle was cleaned.
The muck creating the problem was now evident:

I decided to use chippings (as purchased by the ton to make paths round our house). With a couple of handfuls of these, warm water and Tesco Multi-Surface Cleaner (other brands are available), I covered the pump hole with a finger and held the top closed with the palm of my other hand, I did a "cocktail-shaker" agitation of the bottle. Eventually, I arrived at the result below:

Some of the chippings used are included in this photo. A stolen (from my kitchen) washing-up sponge cleaned-up a few remaining bits of muck clinging to the underside of the bottle neck.
Unblocking Jets:
There is a device at the top end of the tube feeding the screen-wash fluid shown below:

I suspect that this is a Non-Return-Valve, but whatever it is, you need to disconnect it. at both ends. If you have more sense than me or are prepared to learn from my mistake, you will mark which way round it was fitted. There are no obvious markings, but if fitted the wrong way, screenwash will not flow.
I recommend that you point the feed-hose overboard:

I now re-filled the clean bottle with dilute multi-surface-cleaner, and re-installed with the pump fitted. Operate the screenwash several times. After each pump operation blow fluid back into the bottle until bubbles appear. Moving the pipe as above makes it easier to apply mouth to pipe. I was amazed how much muck there was in the pump and pipework. Either put a bowl on the garage floor, so that you can invert the bottle to get rid of this blown-back muck, or do the whole job somewhere where the water etc. will not cause problems.

Unblocking Jets;
I did this by closing the bonnet and directing a jet-wash at the jets. I tried to line-up with each of the jets, to direct a high-velocity stream of water into each nozzle, to back-flush muck down the disconnected pipes. No photos of this, I did not want to get my camera wet and I need two hands to properly aim the jet-wash!
The end result after re-connecting the Non-Return-Valve the right way (eventually!) was four nice jets of clean screen-wash.

Avoiding Re-occurrence
I am sure I read somewhere that washing-up liquid eventually bio-degrades. Perhaps this is the source of "food" for the black muck I had to get rid of. According to the comprehensive records which came with this car, the ONLY time it failed an MOT was "washer jets blocked". I suspect that the previous owner did not use proper screenwash fluid AND the garage who charged for unblocking jets did not bother to do all the cleaning that was necessary.
The moral is: Use the proper stuff with alcohol Iso-propanol and/or Methylated spirits?? and flush-out occasionally.

262 Posts
Milton also works, just leave it in the washer bottle for a 10/15 mins then rinse out. I put a new (standard) pump in as the original one was a bit tired. I can now wash the upstairs windows with it.

17 Posts
I think household dishwashing liquid has salt in it, so not recommended for windscreen washers despite the lovely bubbles!
1 - 3 of 3 Posts