Flushing out a radiator off the car

[pauloliver]

I managed to get an hour spare to pull apart my cooling system on the Porsche. Flushing out the engine has not shown any noticeable poop, however flushing the radiator has in the form of limescale looking stuff and some grime, however it is now running nice and clear after flushing in every hole there is. Is there any reason why I can't fill the rad with white vinegar to break down the crud whilst its off the car and then flush it all out? It certainly looks cleaner inside but I'm guessing those little tubes behind the fins will look like heart diseased arteries. Ideally a radiator recore would happen but I can't afford it right now. The rad looks to be in good condition and I think is fairly new (past 10 or so years) so I'd rather try and get it useable for the summer ready for a fresh rad/rebuild when I have the money.

[taurus]

retrorides.proboards.com/thread/153722/cleaning-radiators

Cheap coke does a good job

[pauloliver]

Excellent, thank you! I did wonder about coke too! Hopefully this will tide me by before I get a recore.

[colnerov]

Hi, don't go too mad with it because removing that build up may mean you end up with pinholes in the tubes where they have corroded through.

Colin

[ChasR]

I am going to be Mr. Boring and Unconditional here after having far too many cooling issues in a few cars and trying various things.

IMHO I would go out and buy a new radiator. The above may work but they may very well also show up shortcomings in the radiator in addition to never being able to fully clear it out. The only true way to ensure a radiator is very clean inside is to rod the radiator but this is a tricky process on cars where the radiator tanks are plastic ; they are prone to splitting ; with the cost of new radiators as well it is also unfortunately a dying art ; I think I was quoted £80 for it to be done when a new radiator for my Stag was £120, and that was without the hassle of having an unmoveable car.

On one of my cars (Mondeo V6) where clean water ran out of the rad with it externally looking great I was gutted when I found the plastic tank had cracked. With a new rad later the car ran cooler than it ever had done for over a year ; no more fan staying on for ages, the car cooled down alot more when I left it alone to go to the shops etc. ; I did learn my lesson with that car from the previous car (another Mondeo V6) I had with a plethora of cooling issues ; no shortcuts worked in the long term (i.e more than a couple of months, although at times it was a week or two (yes, I really did drive it thinking 'how long will the car work for ; WOW, a week, I'm doing good! Maybe I can make it two...)).

On pretty much any car I have fitted a new radiator to despite flushing them like mad the old rad did not come close to keeping it cool. It was the difference between the fan staying on for a few seconds, not minutes. After that, I would buy the best quality antifreeze you can afford (Glytasyn G48 is pretty good IME if you don't fancy trying out something like an OAT). The cheaper blue ones IME tend not to have the best anti corrosion properties meaning that you go back to square one within a few years (i.e a silted radiator).


For a 924 they are not massively pricey either ; on a 944 they are around £300 a rad! I can appreciate cash is tight but it beats being sat at the side of the road (something I got very used to doing with one or two cars at one point) or worse still taking out something more awkward or pricier to replace (a head gasket).

I can appreciate it is not what you wish to hear but I have become sick of almost always working on cars, and the hassle of an unreliable one.

[pauloliver]

Thanks for all the feedback guys, especially ChasR. I decided to take the radiator to be flow tested as it was only a few quid and at least I would know where I stand with it. As expected it was fairly blocked and therefore a new core is needed. I'm getting a quote for Monday, the guy said it would be between £100-200 and the new core would be better than what my car would have come with (and of course better than what I have right now!). I have been taking apart as much of the cooling system as possible to clean it all out, I have a new waterpump to go on and a new thermostat and radiator fan switch.

To add to that I need a new condensor and a recharge for the AC on my Astra, my bank account is going to hate me....