Classic cars forum & vehicle restoration.

[jp928]

With welch plug hopefully fixed, now looking into radiator performance. Timing is now closer to the mark, so its heating up slower, but still going higher than I would like - book says 140F (65C) cruising at 25mph, but I am seeing mid 70s idling. There is a fan fitted to this model, and it is pulling air through. Checked water pump (separate item on front of chain casing, input from rad lower, feeding into the block) and its fully hot, as is radiator shell and lower tank, but lower third of the core is very cool to the touch (~25C). Had the engine idling 20mins with some throttle blips , saw water temp at top in low 70sC, with lower core almost cold. Looks like the hot water from the top is going down the sides of the rad to the bottom outlet. After letting it sit to soak the core comes up in temp, but I think thats just conduction.
Any suggestions on how to clean/flush the core appreciated. Have run some Penrite flush through it once.
thanks
jp 26 Rover 9

[colwyn500]

Bob, old mate of mine, recommended Oxalic acid on my Austin 10. You can get the crystals off eBay. I made a solution of this and ran it through the radiator and block for a few days and then flushed through, having removed the radiator.
Worth Googling?

[BigJohn]

The radiator on my Standard Flying 12 was clogged with lime due to the previous owner using fresh stream water in it, he lived in limestone country. I left two sachets of Aldi dishwasher descaler in it for a few days, over a week if I remember correctly. I then flushed out what appeared to be a breeze block in liquid form.

[jp928]

Bigjohn - following your post, am trying some scale remover - having checked its mostly Citric acid. I think there is some improvement in the temp in the lower part of the core, so persisting with leaving the mix a few more days. Then I will pull the radiator and back flush it with a hose to try to remove more sludge.
Apparently flushing with citric acid is a std , regular process in some models of modern MB engines, so it shouldnt do any harm anywhere. Some descalers I saw said dont expose aluminium for long, and one said not good for cast iron!

thanks
jp 26 Rover 9

[BigJohn]

I was given a Clarke parts washer for a present which also had a gallon of fluid with it, it was just dilute citric acid. I seems to kill algae on my drive as well. I intend to buy the crystals from Ebay when required and dilute my own.

[Penman]

Hi
My mother used to live in a hard water area and I always used citric acid to clean out her kettle, I felt it was much safer than the commercial de-scalers with their dire warnings about making sure the appliance had been thoroughly cleaned after de-scaling.
_________________
Bristols should always come in pairs.

Any 2 from:-
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V8 V10

[lowdrag]

Block off the bottom hose and buy a few litres of white vinegar if your problem is limescale. Fill the radiator and leave overnight then flush. Cleans everything at a very modest price. We live in a hard water area and use it on the kettle, washing machine, coffee machine and anything that moves. Correct that - the toilet doesn't move, but is shiny white!