Radiator flush tips please?

[sami 13/60]

I fitted a thermostat to my 13/60 the other day, as it appeared to have been removed after an overheating issue prior to my ownership.  Having finished, I went to top up the rad, and saw how much gunge etc was showing in the tops of the tubes of the rad, which may explain the overheating in the past.  I want to flush the rad through effectively (with the rad removed) and will also flush the rest of the system as much as possible.

Any tips on how to really do the rad thoroughly please?  We do have a jet washer that could be put to use in some form I expect, and I also have an air compressor........or are there good chemical solutions to use to soak out the rubbish in there?  Any suggestions appreciated.  Many thanks,

Samantha.

[JohnD]

I fear a jet washer is more likely to damage the radiator than clean it!  Compressor, ditto.   The rad isn't built to take more than about 15psi.   Your airline may be usefull to blow out flys etc from the matrix, and a device called a "radiator comb"

To clean it out, with the radiator removed, partly fill it, block the openings and shake it! Turn it to and fro to churn the water inside.  Repeat, until what comes out is clear.   Reverse flush it, that is put the water in from the bottom hose connection, until again the effluent is clear.    The standard click-together hose connector may be a nice fit inside the pipe.

Best to use a radiator flush after doing this, as there will be less  crud for the cleaner to work on.  But repeat with a removed radiator, as the cleaner may loosen bits that won't come out of the drain tap.

Don't forget to flush the block as well, and heater, in reverse direction  - see workshop manual)  I can't recommend a particular cleaner,no doubt someone will.

John

 

[dougbgt6]

Samantha.

following advise on here, from a guy who had tested a few chemical cleaners, I used household washing soda! It worked very well, although the packet said don't use on aluminium. The only ali bits are the thermostat housing and inlet manifold and these aren't delicate mechanisms, so unaffected by the washing soda. I drained the system and put a packet of Waitrose best in and topped up with water. Ran the car for a couple of days got it hot, did 20 miles maybe. Then drained and flushed engine and block with the hose. 

I took out the block's water jacket drain plug and scrapped out a load of crude blocking free flow, however I don't know if there is a block drain plug on your engine.

Doug

 

[AidanT]

Hi 

Agree with Doug on this but it does depend on what "gunk" you have. Is it white calcium carbonate or just brown rust particles?

Aidan 

[Pete Lewis]

i advocate cheap as chips washing soda before you go mad on spending £££s   3 cupfuls should dissolve most crud.

flush the heat matrix  and valve with a hose  as a separate  job when flushing the radiator

its ok to use a garden hose but you wont get the full flow for the size of a rad hose , unless you get lots of plumbing waste pipe and a 20 gallon reservior

up near the roof of the house ( not really usefull but we had to do that to test radiator flow on truck rads )

you can safely leave the soda mix in for a week but no longer 

Pete

[dougbgt6]

Pete, no, use Waitrose Washing Soda! Reassuringly expensive. 

[Pete Lewis]

Is that posh soda ??

[dougbgt6]

Posh soda for posh people! Our beloved leader, Mrs May shops there and I'm sure has a packet under her sink. So, government approved! 

[Pete Lewis]

Ready for a cabinet flush then .

[Clive]

I don't remove the rad to flush them, but do disconnect hoses, usually just at one end. 

And that means all the water hoses on the engine. A garden hose is near enough the same size as the small hoses, so can be pushed an but may need to be held in place. Flush with he garden hose in both directions through the rad, and also go around the engine, not forgetting the block drain plug, which is near the back of the engine below the manifolds. Often completely blocked, and needs a coathanger and other bits of wire/pokey things to get it moving. Don't forget to remove the thermostat....

 

Then as above reconnect all the hoses and add chemical cleaner. I have usually splashed out a few quid and bought holts speedfush or similar, and take the car for a good run to get it hot. Chemicals work MUCH faster when hot, at 80 degrees approx 100x faster than 10 degrees (rule of thumb, speed doubles for every 10 degree rise in temp).The thermostat should be fitted for this so he engine can get hot. You may need to blank part of the radiator with card or tinfoil too to get the car hot, but keep an eye on the temp gauge!

This needs to be followed by a thorough flush,and then fill with water and see if it looks/woks better. If so, drain and fill with 30% blue antifreeze and job done.

This time of year it is no fun though, cold weather and wet hands are not a great combination. Maybe break out the marigolds! 

[sami 13/60]

Thanks guys very helpful, this will be the next job when I can get the car inside out of the weather .....garage full of a friend's "stuff", mid house move ATM, so it may be his hands that will suffer, he he.....a favour for a favour 

Samantha

[Chris A]

I have been watching this thread carefully as I want to flush the system on my 13/60 in spring, so thanks from me too for all the pointers, some of which I knew but some tips I didn't.

I also plan to replace the drain tap on the radiator as it doesn't want to open, or at least without a little serious persuasion, for the cost of a new one why worry too much. Hopefully it will actually unscrew from the radiator . I also have a replacement heater valve on standby as the heater doesn't..heat, again on the basis that while I have the system drained I don't want the car off the road longer than necessary. I have to build in delivery times to France from the UK for some (most) parts.

in passing I will add that I'm going to stick with good old fashioned anti-freeze not this new fangled stuff