Flushing radiator...

[Jim]

If I was to flush out my radiator good and proper, could this cause any problems? My dad mentioned that if the radiator is old then a harsh flushing could cause any cracks or weak parts that are currently being "sealed" or whatever by sludge etc to become worse? Anyone had any experience with this? Should I carry on as planned or not flush it out as well or what?

Also, any other tips while we're on the subject of flushing out the radiator?

Thanks...

 

[Ed]

If you believe its blocked, (which if it is will also mean the rest of the system is in a serious state) then your best bet is to just change the rad. However there is no harm at all in taking a dirty rad out washing it and doing the same for the cars waterworks if they are just dirty.

One way to do this is to just empty the water out fill with clean water, run for a couple of mins then repeat this after its cooled down a few times untill its clear. Then drain again and fill with antifreez (VERY IMPORTANT). All will be well then.

Ed

 

[Jim]

Ok thanks Ed, I guess if it doesn't get a flush then there will be more to worry about with it getting blocked! I'm hoping it'll sort of my slight over-heating issues as I only have to be stuck in traffic for a couple of mins and the gauge will rise to 3/4. Fitted a new stat and it still happens so I'm hoping its this!

 

[Ed]

If you are stuck in traffic and you hear the rad fan cut in and then cut out again. All is fine. You have nothing to worry about.

Ed

 

[Jim]

yeah the fan does cut in, but temp still remains between 2/3 and 3/4. it doesn't rise any more than that so either the fan is doing its job or i'm not in traffic long enough to find out! the fan doesn't make it go back to half way though... don't know if this is a problem or not?

 

[Rusty]

the fan doesn't make it go back to half way though... don't know if this is a problem or not?

Mine does exactly the same thing. Has always done I think. Doesn't seem to cause a problem.

 

[Andrew]

When your going along, you get 30mph + of wind going through the radiator. The second you stop, you don't... it's not overheating, it's just the way the car is designed. Unless the temp gauge sits right at the top, or rapidly moves about for no apparent reason, you've got nothing to worry about.

What Ed says about antifreeze is so important on a mixed metal engine. You get horrible corrosion effects between the alloy block and iron head, and it fills the cooling system with a horrible sludge, and extremely quickly. The old generator project only had plain water in a for a few weeks (not running at all), and that came out a really unpleasant colour.

 

[Arnold]

yeah the fan does cut in, but temp still remains between 2/3 and 3/4. it doesn't rise any more than that so either the fan is doing its job or i'm not in traffic long enough to find out! the fan doesn't make it go back to half way though... don't know if this is a problem or not?

Open the window and turn the heater to do the windscreen, use fresh air and wack it on full! After a minute or two, you'l soon start to see the dial drop!

 

[Jim]

Open the window and turn the heater to do the windscreen, use fresh air and wack it on full! After a minute or two, you'l soon start to see the dial drop!

yeah that works a treat...only my heater has broken! haha..

 

[Andrew]

Thing is, it isn't overheating though, it's just warm. There is no need to worry unless it is right at the top... 2/3 to 3/4 is normal....

 

[Jim]

what sort of temperatures is it at 1/2 way anyway? and at 3/4? about 80°C?

 

[Andrew]

I don't know really - it's just a general rule of car temp gauges that there is nothing to worry about until it is hitting the top. IIRC, the thermostat opens at about 88ºC and the fan switches on at 90ºC, so at a guess:

0% = 50 degrees
25% = 65 degrees
50% = 80 degrees
75% = 95 degrees
100% = 110 degrees

Water boils at a higher temperature when under pressure (as in a sealed cooling system). Boiling is really, really bad for cooling though, because steam doesn't conduct heat away from the metal nearly as well. That's why it goes above 100 degrees. I doubt the gauge is that linear as the figures above though.

 

[Slim]

k10's will more or less run smack on 1/2 on the gauge kin any condition

HOWEVER - if you have super S dials - they tend to read higher than any other ones. sounds stupid, but its true

 

[Andrew]

k10's will more or less run smack on 1/2 on the gauge kin any condition

HOWEVER - if you have super S dials - they tend to read higher than any other ones. sounds stupid, but its true

From the recent swap I witnessed on these, they have a different arrangement with the voltage regulator for the instruments. That would probably be the cause of it. Or maybe the Super S dials make the car perform better and get hotter

 

[Jobe]

Had a similar problem and was worried...ended up deciding to hardwire the fan to acc power so its running at all times the engines on...

Maybe nows not the best times to ask, but aside from maybe burning the fan motor out faster, will there be any other problems?

 

[Arnold]

Had a similar problem and was worried...ended up deciding to hardwire the fan to acc power so its running at all times the engines on...

Maybe nows not the best times to ask, but aside from maybe burning the fan motor out faster, will there be any other problems?

well when the fan is on, the rpm of the engine goes up.. so maybe in the longterm, it'l use more fuel thus costing more to run the car! How much exactly i dont know, probably very little.

 

[James]

That's an interesting comment about the Super S dials, cos I only noticed my K10 was "overheating" after I fitted the Super S dials. That's ok then cos when I sell the K10 the Super S dials won't be on it probably