The Triumph Dolomite Club - Discussion Forum

I've got some concerns that the radiator isn't cooling as well as it should, though it's only in the hot weather that it gets really worrying, and only when in very slow traffic. I've flushed it with Wynns rad flush, and that's not made any big difference - as the weather is getting cooler, it's getting less of an issue anyway.

It was re-cored in May last year, and I've been back to the firm that did it to ask about possible upgrades, etc. They've suggested I first put two dishwasher tabs in for a couple of days, to fully descale the system. But I'm concerned about the caustic soda acting as an electrolyte between the alloy head and block.

So I just wondered if anybody had tried this, what effect they saw, and what alternatives anyone might suggest?

Graham

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The 16v Slant 4 engine is more fun than the 3.5 V8, because you mostly drive it on the upslope of the torque curve.

Factory 1977 TR7 Sprint FHC VVC 697S (Now all of, but still needs putting together)
B&Y 73 Dolomite Sprint UVB 274M (kids!)
1970 Maroon 13/60 Herald Convertable (wife's fun car).

Have you checked your VS output? If that's wrong then no amount of descaling will make any difference. I don't think you'll do any harm with the dishwasher tablets but I can't see this doing any better a job than the proper rad flush.

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Mark

1961 Chevrolet Corvair Greenbrier Sportswagon
1980 Dolomite Sprint project using brand new shell
2009 Mazda MX5 2.0 Sport
2018 Infiniti Q30

What's the "VS output"?

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The 16v Slant 4 engine is more fun than the 3.5 V8, because you mostly drive it on the upslope of the torque curve.

Factory 1977 TR7 Sprint FHC VVC 697S (Now all of, but still needs putting together)
B&Y 73 Dolomite Sprint UVB 274M (kids!)
1970 Maroon 13/60 Herald Convertable (wife's fun car).

25 years ago my 1942 Jeep was over heating, so i went to replace the thermostat only to find there wasn't one fitted. So I used Holts rad flush, I left it in for a month as as I drove round I could see the temperature gradually reducing, when the temp barley got above 50C I flushed it through and fitted a thermostat.

Malcolm

Mark is referring the the voltage stabilizer which provides an accurate reading for the fuel and temperature gauges. It is located on the bulkhead above the fusebox.

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Toledo Man

West Yorkshire Area Organiser & forum moderator
Meetings take place on the first Wednesday of the month at 8.00pm at The Old Brickworks, Wakefield Road, Drighlington, Bradford, BD11 1EA

1972 Dolomite 1850 auto (NYE 751L - Now for sale)
2003 Volvo XC90 D5 SE (PX53 OVZ - The daily driver)
2009 Mercedes-Benz W204 C200 CDI Sport (BJ58 NCV - The 2nd car)
1991 Toyota Celica GT (J481 ONB - another project car)
Former stable of SAY 414M (1974 Toledo), GRH 244D (1966 1300fwd), CDB 324L (1973 1500fwd), GGN 573J (1971 1500fwd), DCP 625S (1977 Dolomite 1300) & LCG 367N (1975 Dolomite Sprint) plus 5 Acclaims and that's just the Triumphs!

Check my blog at http://triumphtoledo.blogspot.com
My YouTube Channel with a bit of Dolomite content.

"There is only one way to avoid criticsm: Do nothing, say nothing and BE nothing." Aristotle

I've used cheap Vinegar with good results. I filled the radiator and left it for a few days.

Sorry yes he's right. The voltage output measured should be 10.2v or near as damn it from memory. If for example you get 12v then your gauges will massively over read, under then they will under read.

You'll need a multimeter to test the output, easy job. If it's an original type, and it probably is then I can pretty much guarantee that it will not be giving an accurate output. There's no point in doing loads of unnecessary work when actually it's just a faulty component. My Sprint used to give a high reading. I needed a new rad anyway but the real difference came when I changed the VS.

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Mark

1961 Chevrolet Corvair Greenbrier Sportswagon
1980 Dolomite Sprint project using brand new shell
2009 Mazda MX5 2.0 Sport
2018 Infiniti Q30

Okay, no, I've not checked the stabilizer. But I've checked the temperatures with an IR thermometer, and it's definitely running a bit hot. There was another thread on this before, but I thought the specific question about dishwasher tabs warranted a new one. The rad inlet temp is about 98C and outlet's about 90C with the 80 Watt fan on. That's after being left to idle for about 20 mins, the fan coming on from full cold in about 10. The last time I tested, the fan would not go off with the car stationary at an ambient temp of about 22-23C, though it had done before I did the pump, when the air temp was a little lower. It does go off after about a minute at 30, and only comes on when stopped or moving slowly in traffic. I hope to do that test again tomorrow – Saturday being the only day I don't have to drive it first thing.

The reason I worry about using dishwasher tabs is that there's a widely repeated recommendation not to let aluminium touch steel in the dishwasher, and I had an old Boot's Sabatier with a s##t metal (zinc-aluminium alloy) ferrule attached to the blade that dissolved over a few years.

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The 16v Slant 4 engine is more fun than the 3.5 V8, because you mostly drive it on the upslope of the torque curve.

Factory 1977 TR7 Sprint FHC VVC 697S (Now all of, but still needs putting together)
B&Y 73 Dolomite Sprint UVB 274M (kids!)
1970 Maroon 13/60 Herald Convertable (wife's fun car).

Dishwasher tablets are highly alkaline, so they will have no effect on limescale.
Radflush is the stuff to use as it will be a developed product by the manufacturer. Don't forget to use the part 2 can of neutraliser after the main treatment.
Tony.

Holts rad flush contains the following active incrediants
Ethanol 1-5%
SOLVENT NAPHTHA <1%
SODIUM HYDRO <1%
PHOSPHORIC ACID <1%
METHANOL <1%
DIETHANOLAMINE <1%

Not very strong but may be worth leaving it in longer, all dishwasher tablets have an acidic content as well, some worse than others.

malcolm

Central heating cleanser, X400. Brilliant stuff leave it in, drive around a while then flush it while hot. Amazing what is suspended in it.

Most dishwasher tablets are salts, even more de-greasers, a load of protein converters with a sprinkling of perfume and a little citric acid. You can get citric acid cheaply in Boots (mix with sodium metabisulphite for a great disinfectant) and put that in as put in a dishwasher tablet, but as has been said, you would need to neutralise that acid to stop galvanic corrosion afterwards; that's probably why the Holts heavy duty Radflush comes in two bottles.

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Current fleet: '75 Sprint, '73 1850, Daihatsu Fourtrak, Honda CG125, Yamaha Fazer 600, Shetland 570 (yes it's a boat!)

Past fleet: Triumph 2000, Lancia Beta Coupe, BL Mini Clubman, Austin Metro, Vauxhall Cavalier MK1 & MK2, Renault 18 D, Rover 216 GSI, Honda Accord (most expensive car purchase, hated, made out of magnetic metal as only car I've ever been crashed into...4 times), BMW 318, Golf GTi MK3 16v x 3

Radflush have an H & S data sheet on ingredients here.

http://www.partinfo.co.uk/files/RK3R%20 ... 20MSDS.pdf

Summary : Part 1 is 10 to 30% citric acid. That makes sense for limescale.
Part 2 is Sodium Silicate. Not sure what that does. Any chemists on here ?

The ethanol / methanol listings may help with oil residues but not limescale.
Tony.

I used white vinegar...cheap as chips and leave it in for a few weeks then flush.
If you need to do another flush it costs next to nothing to pop down to Tesco's and get some more.

Saying that however....if the rad it blocked, then no amount of flushing will fix it. Its WELL worth dropping to a rad specialist and they can rod it to clean any blocked tubes and give it a general service and paint.
Surely though...the cost of the replacement/alternative radiators from Saabs and Vectras and the like is so low (especially over there in the UK) that wouldnt it be worth just getting a new one for peace of mind?

The sodium silicate might serve a few purposes other than as the assumed neutraliser of the citric acid, seems it's a sealer:
It also has clumping properties when there are fine particles in water, as well as being the key ingredient of exhaust sealer/lubricant paste!

The alternative rads such as the typical SAAB one do need some bodywork alterations though don't they? I think this might put people off, it does me, I don't mind reversible mods but I balk at doing any hacking about.

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Current fleet: '75 Sprint, '73 1850, Daihatsu Fourtrak, Honda CG125, Yamaha Fazer 600, Shetland 570 (yes it's a boat!)

Past fleet: Triumph 2000, Lancia Beta Coupe, BL Mini Clubman, Austin Metro, Vauxhall Cavalier MK1 & MK2, Renault 18 D, Rover 216 GSI, Honda Accord (most expensive car purchase, hated, made out of magnetic metal as only car I've ever been crashed into...4 times), BMW 318, Golf GTi MK3 16v x 3