Radiator flush

[chris240]

a few weeks ago I removed my radiator and gave it a big reverse flush, as well as the block , I installed the radiator then ran the heater for a few minutes then drained again, did this about 3 times to ensure there was no sludge or crap left behind. Somehow the flushing has caused the water pump to  lose its seal against the block, basically, debris from the flush caused a pinhole or tiny gash in the waterpump gasket, thus causing it to dribble water/coolant everywhere !! talk about bad luck....

I checked this with a friend who is a decent mechanic and he confirmed my suspicion that its not totally uncommon for this to happen on older blocks when flushing them out. Anyone else had this sorta happen or am I the first !!

chris

[Zedman240®]

I've heard of it happening before. You are right, the flushing dislodges crap that was covering a hole and then you are left with a leak. It's good to find it now rather than on a 38' day in the middle of peak hour with all your frozen foods in the car....

[Zeddophile]

As zedman says - you disturb sludge or rotting gasket/rust etc that was previously holding together your gasket/metal pipe/insert important part here, and voila you suddenly have a leak that wasn't there five minutes ago.

 

As the old saying goes "If it ain't broke, don't fix it."  The number of times you wish you'd adhered to that rule rapidly mount up when you're doing your own work on cars.

[sco_aus]

a few weeks ago I removed my radiator and gave it a big reverse flush, as well as the block , I installed the radiator then ran the heater for a few minutes then drained again, did this about 3 times to ensure there was no sludge or crap left behind. Somehow the flushing has caused the water pump to  lose its seal against the block, basically, debris from the flush caused a pinhole or tiny gash in the waterpump gasket, thus causing it to dribble water/coolant everywhere !! talk about bad luck....

I checked this with a friend who is a decent mechanic and he confirmed my suspicion that its not totally uncommon for this to happen on older blocks when flushing them out. Anyone else had this sorta happen or am I the first !!

chris

And we are on tight water restrictions Chris!!!

 

Yeh sounds right, at least its easy and cheap to fix and as said, better now than later.

[chris240]

I should get out of it ok...

new water pump = $59

gasket = $5

labour = 2 blokes 1 hour + 6 crownies

[620Z]

My understanding is that the coolant additive actually thins the water. So if you only had water in it before then change or add coolant to your radiator then it might find a minute whole that normal water particles couldn't make it through. I had a similar problem when I added coolant to when I only had water in the radiator. You forgot to add $50- for another bottle of coolant assuming you might have to drain it again changing the water pump. Pain in the butt. Better to sort it out now than on the road though.

[C.A.R.]

If I could make a recommendation; instead of using the normal green 'Ethylene Glycol',

Poor in a bottle of "Redline 'Water Wetter' ".

 

This stuff is FAR superior to the old Ethylene Glycol, as it doesn't raise the boiling point of the water,

it INCREASES the cooling capacity of the water when its added = cooler running engine.

 

Retails from 'Bursons' for around $25.

HIGHLY recommended!

[chris240]

The car did have plain water prior to flushing, and I foolishly added a a heap of Glycol concentrate which was exactly when the leak started (bit more than suggested actually....) arrr its all making sense now ! No more green diswashing liquid.

[HELLFIRE!]

I feel for ya Gonzo240, but like the others have said, the timing is in your favour. Once you have this sorted you can drive with confidence.

 

Awesome and informative thread. That redline stuff sounds interesting. I am about to sort out my radiator soon so will keep these comments in mind, probably should get a new gasket before I start.

 

Question: How many of you have bought a Z and looked in the radiator only to find crappy water?

 

3 times so far for me. I think it's a consequence of the Z's not having an overflow container. ie any "coolant" that goes out the pipe is gone, never to come back.

[Zedman240®]

While we are talkin about radiators and cooling systems, I just want to know if its just me or if it happens to all Z owners, my current 240Z and previous two 260Z's always without fail, when topping up coolant to almost the top, would spit out almost the same amount of coolant, and stick to a particular level. Not enough to over heat, but the next time I check, enough to make me add more water and start that cycle again......

[lightmaster240z]

Me too plus add in atrip to natrad. To tell me it was all fine

[620Z]

That's why man invented the overflow bottle. When you turn off your motor the water heats up expands and overflows onto the ground. If you have a bottle it would go into that and then it gets sucked back in when the car is driven again and heats up to normal temperature. You only need a small bottle. I slid mine beside the radiator using an nice black bottle that used to be for polish. Drilled a hole in the top for the hose to slide in. The problem is finding a nice bottle shape to suit your space. I looked in Supercheap around all the plastic bottled stuff like polish etc. Bought it for $6- or os and jobs done. Oh make sure it is a stick plastic. I did this after searching wreckers and not finding the shape I wanted.

[chris240]

if anyone is looking at flushing this weekend......remember to turn the heater on for a few minutes then drain the radiator (allow) to cool a bit, amazing what comes out. Or disconnect heater hose(s) and run water from garden hose thru the heater hose geeeently, while also running the heater to get the gunge out from the heaterbox.

The heaterbox on zeds is the lowest point that holds water and is always forgotten when flushing the cooling system.