image of Holts Radflush 2-Step (2x250ml)

Item: 777607

Holts Radflush 2-Step (2x250ml)


(Unit price: £0 per 100ml)

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  • Holts Radflush 2-Step

    Holts Radflush 2-Step unblocks your radiator quickly to prevent overheating, It comes in two easy to use parts for maximum results.

    Holts Radflush 2-Step Extra Info

    • Suitable for use with all engines
    • Flushes blocked channels
    • Lasts for up to 12 months
    • Part 1 rapidly removes limescale and rust particles
    • Part 2 protects with a neutralising and anti-corrosive action
  • Rated 3.2 out of 5 by 9 reviewers.
    Rated 5 out of 5 by well worth it Had a problem with heating system on the car, was told to try this. I normal take my car to a garage to get repaired. Folwed the instuctions on both bottles and to my shock all this matter of gunk drain from my water system after letting it run for about 30mins. wow i thaught that dont look good. So i emptyed the 2nd bottle in to the syslem with fresh water. after she had cooled down. This time when i emptyed the system it was realy clean. If you love your car then i would say do this at least once, its worth every penny. 22 December 2011
    Rated 1 out of 5 by Blocked heater element This product fails to remove the blockage in BMW heater elements. The cause of which is build up from old coolant (BMW lifetime fill!). It didn't even remove the scale on the pipework viable from the expansion tank. I'm not sure this product actually does anything. Instructions do not state never to add cold water to a hot system. Luckily I already know this. 16 December 2013
    Rated 4 out of 5 by Radflush Does what it says on the tin! Works perfectly well. 12 July 2013
    Rated 5 out of 5 by Good product I had a dirty enough radiator it had some limescale & (I think) a bit of algi (Due to a fishy smell when I opened the cap and the green color.) The product worked very well to clean it out, the coolant was a very dark green when I drained it out. It's easy to use if your radiator drain plug is easy to get to (Which mine fortunately is.) I'm very impressed with the difference it has made to my engine and overall driving experience. 04 February 2013
    Rated 1 out of 5 by get a better one did exactly as it said ,and it made little difference,i even tried to ring holts to complain, but its a non speaking automated rubbish fake helpline,, if you need to clear your engine simply pay more and get a better one 28 November 2012
    Rated 1 out of 5 by Didn't do what I expected of it I wasted half a day using the radflush to prepare the system for wondarweld. I may as well have flushed my money straight down the drain instead as it didn't remove any gunk in the system. To be fair my headgasket had gone and I was expecting it to remove the oil in the rad - it would be helpful if it made it clear on the package that it wasn't capable of this 01 April 2012
    Rated 5 out of 5 by Radflush Heater Matrix Clean out Does as it says although the small print instructions were difficult to read! Beware the instruction to flush engine with cold water, use warm/hot to prevent damage to engine. Got rid of the sludge leaving a clean system. 20 December 2011
    Rated 2 out of 5 by Instructions need to be checked/rewritten The product may work but beware that using a chemical flushing agent can lead to leaks, perhaps because the removed limescale was blocking a hole but more likely because it can damage the bond in aluminium- plastic radiators. The instructions are long, quite confusing and probably incorrect in so much as the instructions for part 1 if followed to the letter would have you draining the flushing agent when hot (dangerous) then flushing the hot engine with cold water from a hose (good bye head gasket). The instructions for part 2 then ask you to add cold water to a hot engine, drain again when hot and flush the hot engine with cold hosepipe water once again. Surely that's not what's meant but it's what it says. The fact that part 2 must be used "immediately" after part 1 also implies that you should not let the system cool down. No mention is made in the instructions about the danger of draining hot fluids nor of the potential damage to the engine through thermal shock. All this means I feel unable to use this product and regret buying it. Another query for me is the strength. Stated to be suitable for 10 to 70 litres coolant capacity. What car has a coolant capacity of 70 litres? Even 10 litres is a large system (my Volvo V70 takes about 7 litres). This suggests to be me that half or even a quarter of a bottle is enough and using a full bottle may do more harm than good. 22 May 2011
    • 2016-09-23 T09:02:08.401-05:00
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Some of the parts we sell here at Halfords have been reconditioned. These will carry a Refundable Deposit or an extra surcharge amount. When you add one of these reconditioned items to your basket, we'll add this extra cost automatically.

Once you've sent us your old item we'll check it over, and then refund you the full surcharge as long as everything is ok.

Before you return your old unit please make sure it's in re-serviceable condition. So if you're returning caliper casings, you'll need to double check they aren't badly damaged or broken. If the part you've sent is found to be unserviceable, we reserve the right not to refund the surcharge.

Please note that if you're returning your old unit to our National Returns Centre then this will be at your own expense.

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Holts Head Gasket & Exhaust Repairs

Holts Radflush 2-Step (2x250ml)

£6.99 Prevent overheating and protect your radiator with Holts Radflush.