Thread: Defender Radiator Maitainance?

I'd disconnect the heater and flush the radiator and block, then flush the heater seperately with lower pressure.

At a minimum disconnect the hoses and inspect for splitting or bubbling.

Get all the residual coolant out and put some corrosion inhibitor in. Unless you NEED antifreeze, avoid the glycol stuff, as the pH of that is dependant on the concentration, and you could cause damage with dilute amounts.

I put antifreeze (GREEN) in mine, but next time I'll just stick to the corrosion inhibitor, it's better for the environment and poses less risk to the engine. The ant-freeze cost me about $30 for a flush and fill at the radiator place, but recently we did Minnimoochas and BrendanBs Defenders with Penrite anticorrosion (RED) and that was only $12 for a 500ml concentrate to do the whole system.

I would get it flushed and rodded for piece of mind by a radiator specialist. Worth it for piece of mind. Better to do it on your terms than 150kms from nowhere and cook an engine. The price of radiator if you shop around is quite good.
A mate ballooned his 100 series radiator last week, Toyota $1500, Local ARB shop $600, Coventry $600 then $540 when fronted with other price, Natrad $650.

Originally Posted by Michael2

I'd disconnect the heater and flush the radiator and block, then flush the heater seperately with lower pressure.

At a minimum disconnect the hoses and inspect for splitting or bubbling.

Get all the residual coolant out and put some corrosion inhibitor in. Unless you NEED antifreeze, avoid the glycol stuff, as the pH of that is dependant on the concentration, and you could cause damage with dilute amounts.

I put antifreeze (GREEN) in mine, but next time I'll just stick to the corrosion inhibitor, it's better for the environment and poses less risk to the engine. The ant-freeze cost me about $30 for a flush and fill at the radiator place, but recently we did Minnimoochas and BrendanBs Defenders with Penrite anticorrosion (RED) and that was only $12 for a 500ml concentrate to do the whole system.

Hmm, dare i suggest you pose less risk to the engine by using the correct anti-freeze, anti-boil at the correct concentration ?
As well as changing the freezing/boiling points, it also does other useful stuff like minimising/eliminating cavitation erosion, which is a particular problem with diesels.

Maintaining the correct ratio is easy if you have it right at the start, and the correct ratio is just as important with any corrosion inhibitor, either as part of the additive package of the coolant, or added as a stand alone inhibitor.

Just been through this myself - '95 Defender

Had no overheating problems, but had new waterpump, thermostat, hoses and coolant just in case.

I ended up with a rising temperature gauge climbing cunningham's gap boxing day.

Took the rad out to get rodded and found that the fins were starting to crumble. Had it recored. Old one was quite blocked.

I'd suggest getting your's rodded. Taking it out can reveal it is in worse state than you thought.

Thanks Fellas, think i will get it done and replace hoses as well, Ya making me neeeeeervvvoouus!!.

Cheers
Sumo

Just one quick one. When flushing the radiator don't let the water pump dry out. When I last did the radiator and the timing belt I had to replace the water pump both times, because the seals dryed out and the pump leaked.

Regards

Originally Posted by sumo

Thanks Fellas, think i will get it done and replace hoses as well, Ya making me neeeeeervvvoouus!!.

Cheers
Sumo

No need to get nervous, but if the radiator is original you need to realise it is 12 years old. It all depends on how it is looked after as well. If correct grade coolant has been run and it has been flushed and relaced at regular intervals then all may be good. But as with other parts radiator cores have a finite life. Radiator specialist recomend a power flush and rodding every 5 years, I think this may be excessive especially if you know the history of the vehicle and its maintenance schedule. I would get mine done after 10 year and then every 5 as prventetive maintenance. Make sure you find a radiator mob you can trust.

Originally Posted by rick130

Hmm, dare i suggest you pose less risk to the engine by using the correct anti-freeze, anti-boil at the correct concentration ?
As well as changing the freezing/boiling points, it also does other useful stuff like minimising/eliminating cavitation erosion, which is a particular problem with diesels.

Maintaining the correct ratio is easy if you have it right at the start, and the correct ratio is just as important with any corrosion inhibitor, either as part of the additive package of the coolant, or added as a stand alone inhibitor.

Hi Rick,

I thought the same, but both the Natrad Radiator guy who did my radiator service & coolant and the Penrite factory guy, both strongly recommended using just the inhibitor.

They didn't think that changes to boiling temp were significant, and only recommended the anti-freeze if I were going to the snow.

Many (17) years ago I used a Green coolant from Penrite (hasn't been available for many years) and that dropped the operating temp of a diesel by 8 degrees C. So I had always thought the Coolant was better than the Inhibitor.

My reasons for changing to the inhibitor with the next radiator service are :
1. I don't stay at the snow overnight. (If I could afford that I'd be taking a RRS).
2. The glycol contaminates ground water easily and should be disposed off properly, the inhibitor can just be drained out.
3. The inhibitor's concentration is not critical to its function.

I would have thought the Penrite racing inhibitor would have dealt with the cavitation issues you mention, but I don't know enough about this stuff, so tell me more - or I'll raise it with the experts next service.

Thanks for the ongoing education.