How to Flush out a Mack 237 Radiator & Block?

Hi Fellas.

Just wanted to ask all you smart and knowledgeable blokes what is the best way of flushing and cleaning the coolant/water out of the radiator and engine block.

I have been told to get it hot flush the old water out, fill it up again with some radiator cleaner get it hot again then flush it out and fill it up with the mack premix lime cordial, i can get the Mack cordial at cost so that heaps, also i would think that it would also be a good idea to put in a new water filter.

-Monty

Monty
GuddayM8
Wot we do
when we get round 2 do n it
is after the truck has cum in off the rd
while tiz still hot we drain water from bottom of radiator tank
make sure heater controls R on (so it will also drain)
then remove any plugs B low the thermostat in engine block the lower the better to drain off all water
Th@ B the simplest way with out taking thermostat out
Wait till donk is cold B fore filling with soft clean water
U can also reverse flush the core by connecting hose to bottom of radiator n it will then flow out radiator filler
if the water still looks dirty keep the water flowing till it clears
give the truck a few days work n repeat the above procedure
till the water looks clean th@ U dump from truck
repeat as many times U like
(The BAD news is Mack 6 cylinder engines R prone to electrolisis B tween #2-#3 cyl)



Cya

[ch9786]

Thanks swish man, as always you are a fountain of knowledge

-Monty

Cleaning your cooling system
I uas Fleetguard Restore. it is one of the best cooling system cleaners
i have used. You could also Washing soda cheap at the corner shop.

I use Castrol anti freeze anti boil the glycol helps in the heat transfer.
I use 30% and a 20 litre drum might cost, but it is worth it in the long run.
The amount of chrystals in the Mack water filter is a joke.

As for Electrolysis.It occurs when an electrical current tries to find
a path to an electrical ground.

I will take swishy to task as a mack block is prone to electrolysis between 2 and 3.

I have earth straps fron radiator to ground
From block to ground and the big trouble with the air to air
engines is the air to air box must be grounded as well
Mack air start engines don't have a earth lead from starter
the radiator is rubber mounted. the engine is rubber mounted

I have seen plenty if air boxes eaten through. put a ground lead on and it will never happen

MY Mack engine is 86 year, Rebuilt in 6/96
and last rebuild in Jan 7/07 The block and air box is in perfect condition Electrolysis Nil.... Mark

Thanks Mark, i take it the earth straps go from the engine to the chassis and the same with radiator.

I take it that you have used the mack filter and the mack coolent then, is there another filter that is better like a fleetguard ?

dont have a air to air so i am safe.

thanks Mark. so i take it that you still you still use the old flintstone/ R Model ?

-Monty

Monty
i just use old battery cables or whatever is laying around.
I have seen a lot of air to air box's eaten out over the years
with electrolysis it usualy eats disimilar or the softer metals first
All i can say is the engine on mine is perfect. Using a good coolant
even after 8 or 9 Years the inside if the block is just shiny metal. The last rebuild even the engine recoditioner commented how clean the
inside of the water jacket and the heads were. He asked me if i had it hot tanked
as for filters i only use Mack
, I just buy a six pack and 3 drums of oil

There is two types of water filters. ESI usualy small filter with two spin on oil filters.

ESI plus, bigger water filter with 3 spin on oil filters
Fleetguard filters are ok

Just flush it out and use a good coolant. I just use castrol anifreeze anti boil as i use it in every thing else

The coolant mix, not enough a waste of time. too mutch and it can become acidic
And yes the old Mack is still going all day every day........Mark

Mask spring specials
Coolant for Monty



www.mack.com.au/Content/Attachment/MackMart_Spring2009.pdf

the thing about good coolant
intercooler no cavitation no eletrolysis
Yep old mack failed again

water Rail clean as

inside Head