Mack E7 Etech what to do as tap water was run rather then coolant

[Gorilla]

Hi Everybody,

Previous owner ran water rather then coolant and its a nice rusty hue and i am planning on doing a flush of the cooling system consisting of:

*drain water out

*put in fresh water, run engine then drop again after 20 minutes

*if dirty water coming out then repeat previous process

*if clean then put in coolant system flush with fresh water and follow instructions

*flush system out of with fresh water

*put in distilled water to flush out all/most of the fresh water and run engine for a 20 minutes

*Put coolant concentrate mixed to highest level with distilled water

 

This will be fine BUT i have a concern and that is the heat exhanger tube for the oil, i know they can fail and have been toying with the idea of removing it and cleaning it before i put in fresh coolant.  Also tossing up taking the radiator to a radiotor place to get it reconditioned as a precaution.  What is everybodies thoughts?

Thank you in Advance,

Chris

[Joey Mack]

Without seeing the issue up front, can you run several cycles of dish washer powder until its clean. We use Cascade in the states. There are other brands to use. 

[fjh]

8 minutes ago, Joey Mack said:

Without seeing the issue up front, can you run several cycles of dish washer powder until it’s clean. We use Cascade in the states. There are other brands to use. 

Put premixed coolant in save your buying distilled water!

[Geoff Weeks]

Coolant filter, add one if it doesn't have one!

[Gorilla]

would you guys be concerned about the state of the radiator or heat exchanged ?  Im building the truck to do long runs and it gets hot here (40+ degrees celcius) and concerns are running in my mind as to weather to just replace the radiator and heat exchanger?

 

[Gorilla]

5 hours ago, fjh said:

Put premixed coolant in save your buying distilled water!

works out cheaper to use distilled water with concentrate

[Gorilla]

4 hours ago, Geoff Weeks said:

Coolant filter, add one if it doesn't have one!

if it does not have one can you retrofit them to the etech? 

 

[Joey Mack]

Yes. There are some small steel lines needed to bleed air, do have pictures of the front if the engine, including the left front corner and the water pump, and the right front  corner including the lower corner. 

[Geoff Weeks]

8 hours ago, Gorilla said:

if it does not have one can you retrofit them to the etech? 

 

Yes, they just get plumbed from the pressure side to the suction side of the waterpump.  Most bigger filter mfg sell the spin on filter heads.

If I were you, I'd install the filter and run it for a while. If you have overheating problems change the radiator. That way you give the filter a chance to work, and not put a bunch of crap into the new radiator from the rest of the cooling system.

Coolant filter are a bypass type filter, meaning they can plug and cause no running problems. If you notice the filter is cool after running, the filter is plugged and you need to replace it. (doing its job). Once the crap is out of the system, the filter will keep new stuff from building up..

[Gorilla]

11 hours ago, Joey Mack said:

Yes. There are some small steel lines needed to bleed air, do have pictures of the front if the engine, including the left front corner and the water pump, and the right front  corner including the lower corner. 

Ill take some pics tomorrow when im at the truck, very little information online on the Quantum and its unique to both renault and macks so fun times  hahaha ;)

[Gorilla]

11 hours ago, Geoff Weeks said:

Yes, they just get plumbed from the pressure side to the suction side of the waterpump.  Most bigger filter mfg sell the spin on filter heads.

If I were you, I'd install the filter and run it for a while. If you have overheating problems change the radiator. That way you give the filter a chance to work, and not put a bunch of crap into the new radiator from the rest of the cooling system.

Coolant filter are a bypass type filter, meaning they can plug and cause no running problems. If you notice the filter is cool after running, the filter is plugged and you need to replace it. (doing its job). Once the crap is out of the system, the filter will keep new stuff from building up..

Going to look into it today, although i dont have overheating problems just coolant is either really old and rusty or its water and im not game to taste it and see if it is coolant hahaha.  Plan is to put a camera into the radiator once ive cleaned it to see what its like inside and then decide weather to replace the radiator.  Truck is not overheating as such, more so preventative maintenence.

[The Heinz]

I had the same issue with my pickup, still having it actually. Previous owner put water in and I never knew until I checked recently. I pulled the lower radiator hose and flushed it using a garden hose until it was completely clear. Did the same with the heater core, which we knew would eventually clog being the highest point in the cooling system on my truck. It eventually plugged so solid that no heat at all would come out of the vents, so that ended in a heater core replacement. I plan to keep flushing like that every once and a while, because I know it's still nasty in there, but I've been afraid of running anything through it other than water. Think Cascade powder is good to use? 

[h67st]

I remember the old timers used to use vinegar to remove rust in the cooling system, but I don't know the ratio to use with water.

[Gorilla]

On 4/8/2025 at 12:11 AM, The Heinz said:

I had the same issue with my pickup, still having it actually. Previous owner put water in and I never knew until I checked recently. I pulled the lower radiator hose and flushed it using a garden hose until it was completely clear. Did the same with the heater core, which we knew would eventually clog being the highest point in the cooling system on my truck. It eventually plugged so solid that no heat at all would come out of the vents, so that ended in a heater core replacement. I plan to keep flushing like that every once and a while, because I know it's still nasty in there, but I've been afraid of running anything through it other than water. Think Cascade powder is good to use? 

On a really rusty looking coolant reservoir/ plastic overflow bottle i used the following: vinager, bleech, CLR (worst crap ive ever used i must note), boiling water, dish washing detergent, and baking soda two types of laundry powder and can report vinegar was the best, CLR was by far the worst and im pretty sure boiling water did more.  Trick i found was to use cat littler (non clumping type) into to container an shake it about which did losen the crud quite a bit but 30 flushes and about 6 hours and i must say ive only got to the point i can make out the water level without taking the cap off............win?  Not sure.

 

[Joey Mack]

Hell of an effort.. 

[Gorilla]

Update:

one radiator hose was recoverable, rest were too close to failure so replacement, given the amount of crud i found in the system i am tomorrow taking the radiator into a radiator specialist and most likely going to rebuild it with new core and while im at it will add a few more cores as my view is can never have too much cooling capacity.  Also noticed the truck has a pneumatically activated radiator fan.......... so looking into converting to a 24v electric fan, not a fan of engine driven fans, they rob power, prone to failure and never had an electric one fail in any application yet.  Found one that does 10,000cfm which i suspect is ample for the application, waiting on the company to get back to me, their made in USA.......  mob is called "electric fan engineering" image of a comparison to a standard thermo fan

[Gorilla]

3 minutes ago, Joey Mack said:

Hell of an effort.. 

when a new plastic tank is 300 bucks........ i figured id try.

[Geoff Weeks]

Nothing is free, that electric also loads the engine. It turns at a single speed, and can't be mechanically locked to be drive all the time like most engine driven clutches can. When the electric fails, it is done and you have no fan.

Your choice, but I would never use an electric in that application.

I have had two electric fan clutches, both worked well. One Facet and one OEM (on a car) Both had ways to "lock" them mechanically .

The old Bendix spring applied, air released clutch is my #1 with the old Horton air applied #2  Had more air leaks on the Horton than the Bendix. 

[Gorilla]

54 minutes ago, Geoff Weeks said:

55 minutes ago, Geoff Weeks said:

Nothing is free, that electric also loads the engine. It turns at a single speed, and can't be mechanically locked to be drive all the time like most engine driven clutches can. When the electric fails, it is done and you have no fan.

Your choice, but I would never use an electric in that application.

I have had two electric fan clutches, both worked well. One Facet and one OEM (on a car) Both had ways to "lock" them mechanically .

The old Bendix spring applied, air released clutch is my #1 with the old Horton air applied #2  Had more air leaks on the Horton than the Bendix. 

I understand nothing is free, and yes it goes at a single speed irrespective of the engine or alternator output..... thing is i have four 920ah batteries so that will buffer it.  As for the electric fan failing, i know it can happen but these fans are made in usa and brushes are easily replaceable while its on the truck and short of that nothing really can go wrong unless i abuse it (which i wont).  Reason im looking this way is that i believe i have a horton air operated clutch and it needs a seal kit put through it as is leaking, i cannot understand how it can be 100% leak proof as its a rotating assembly so it must leak by its nature and i hate air leaks. 

 

[Geoff Weeks]

"thing is i have four 920ah batteries"

That I got to see! I had 4 155 amp/hr batteries for a total of 620 amp/hrs and they all are bigger than the std gp 31 truck batteries.

Deep cycle gp 31's are 135 amp/hrs, cranking gp31's would likely be a bit less.

I think you are confusing CCA with amp/hrs, they are not the same thing.

When an electrical load is placed on the truck, the alternator will take up that load up to the capacity of the alternator, then the batteries start depleting. Converting from rotational belt to electrical and back to rotational is not an efficient process.  Fixed RPM means that load is fixed. It also means it can't reduce draw at lower loads and can't increase when needed, like pulling a hill. So when a fan is needed to pull air across the condenser, you'll have only one choice, with an electric fan, where as an engine driven fan can turn slowly at idle,using very little power.

A/C compressor use "face seals" to hold in a fix amount of refrigerant at pressures exceeding those of the trucks air system. The older Hortons anyway, not sure on the new stuff, also use face seals for the air. They also use O rings for the piston seals.  I find moisture in the air causes most problems, be it with the fan clutch or elsewhere.

No mfg of a truck or bus engine relies on an electric fan, that should tell you something right there. On motor coaches where direct belt drive for the fan is not practical, hyd drive is used.

Your money, your choice, but wouldn't be mine.

Edited Monday at 01:43 PM by Geoff Weeks

[Geoff Weeks]

Thing I'd want to compare is the free-air CFM of the factory (at rated speed) and the CFM of the electric. I'm not sure where you would obtain the spec's but that is what is important.

[Geoff Weeks]

My air ride truck and trailer would go 45 min running down the hiway between compressor cycles. I am not stranger to eliminating air leaks. Anything less then 15 mins while running down the hiway between cycles and I was looking for leaks.

few trucks I have been around can meet or beat that, and mine had air fan clutches, just saying.

[Joseph Cummings]

The electric fan thing is doomed to failure. You are talking about at least 25 HP to run a fan. The motor on that fan in the picture is nowhere near 25HP.

25hp x 746 watts / 24 volts = 777.083333333 amps. And that is not even allowing for losses. 

[Geoff Weeks]

2 hours ago, Joseph Cummings said:

The electric fan thing is doomed to failure. You are talking about at least 25 HP to run a fan. The motor on that fan in the picture is nowhere near 25HP.

25hp x 746 watts / 24 volts = 777.083333333 amps. And that is not even allowing for losses. 

They only list a max Hp of 1.25 Hp for their fan motor.

I've pull heavy over the Big Horn mts, 3/4 of an hour wide open at less than 25MPH, Glad I had a mechanical fan drive and didn't find 1/2 way up that the electric couldn't cut it.

That is a hard test of any equipment.

There is just no way a 3 bladed fan can move the air of a 7 or 9 blade of the same diameter. Now most have a "ring" on the ends of the blades to prevent the air being thrown off the ends of the blades, and the hole shooting match is in a shroud to duct the air flow.

This is the place that he is talking about:

https://www.electricfanengineering.com/turbine-electric-fans/over-the-road-truck-tractor/

As I stated, no way I'd go down that road.

[Joseph Cummings]

54 minutes ago, Geoff Weeks said:

They only list a max Hp of 1.25 Hp for their fan motor.

I've pull heavy over the Big Horn mts, 3/4 of an hour wide open at less than 25MPH, Glad I had a mechanical fan drive and didn't find 1/2 way up that the electric couldn't cut it.

That is a hard test of any equipment.

There is just no way a 3 bladed fan can move the air of a 7 or 9 blade of the same diameter. Now most have a "ring" on the ends of the blades to prevent the air being thrown off the ends of the blades, and the hole shooting match is in a shroud to duct the air flow.

This is the place that he is talking about:

https://www.electricfanengineering.com/turbine-electric-fans/over-the-road-truck-tractor/

As I stated, no way I'd go down that road.

And going from mechanical to electrical, and then back to mechanical from electrical is two extra times entropy is going to rear it's ugly head

It's just adding more I2R and friction losses to the system;

If you go down the line of thinking that you can make energy appear out of nowhere, or make energy disappear, you end up believing in things Like Stan Myers "it runs on water" or this rediculas thing of Mr Yoon's