Hi, I've got all the components off the front of my engine(440) and its still in the car. My question: With the water pump housing off, could I flush the engine by using a garden hose on one opening and the contaminated antifreeze would come out the other hole on the front of the engine?

yep, absolutely! messy, but effective. You could also crack open the petcocks on the sides of the block.

do the heater core too if it has a manual water valve as apposed to vacuum.

You should remove the water-jacket plugs on the sides of the block so the lower part of the cooling system flushes as well. Good time to replace those plugs with actual petcocks, maybe adding drain tubes as I do on the hot rods & race cars.
Also remember that anti-freeze has an attractive taste to animals, but is deadly to them.

yes but do the pair of block holes on each side as they are isolated (the top ones on each side come together into the center at the stat housing). You are thinking it is partly plugged so as said I would pull the freeze plugs & blast it out with a car wash wand but that would entail towing it there. EDIT & it'd be a good idea to stick the wand in the upper hole on each side to back flush

I agree with topside and RapidRobert: open the drain plugs on each side of the block to be sure of flushing all of the old coolant from the engine.

When I got around to seriously flushing my own block, I discovered that the drain on the block was completely plugged. After reading up on rad flushes, I ended up running 1 kg of citric acid through my engine to remove rust and scale. Citric acid is safe for iron, brass, and aluminum and my cooling passages now look like they were freshly cast.

I did a write up about this for members of my car club: Cooling System

Since you are doing a thorough flush from the above advice. Follow it up with an impurity free fill.

Since the block will be left with garden hose water in it. Fill it with distill, drain and repeat a few times. This leaves the block for of distilled instead of garden hose water, even after a drain.

Then determine the capacity of your cooling system. Divide that capacity by 2. Add that amount of concentrated coolant to your system. This will then be a true mix of 50/50.

Sometimes the drain plugs are rusted in place and if the engine is in the car they can be hard to deal with. You can also suck most of the water out of the block when the water pump is off by using a hand vacuum pump.

Or a wet / dry shop vac.

When you flush it out, be on the look out for sand or sand type material. When I pulled my engine and popped the freeze plugs out the area behind was packed solid with sand. You can search here or other forums about the sand left in the blocks from the casting. I didn't keep the sand but as we broke the engine down there was literaly more than 2 cups of crud or sand flushed out of the block.

If the system is that dirty, go through with your flush (including block drains). Then, put the pump back on it and dump half a bottle of dishwashing detergent in the radiator. Top with water. Cap it and run the engine for 20-30 minutes.

The cap will prevent it from becoming a soap suds monster.


Drain and fill with your usual coolant mix.

Robert ,
I see you as a beneficial member of this site, helpful
and very knowledgeable.

That said I must add;
This is not exactly what I would consider a conscientious suggestion.
Car wash owners hate this.
So does the next person wanting to clean their car.
It leaves greasy crud on everything.
A large part of the reason so many have closed around here is the oil and grease contaminating the plumbing.
Home use pressure washers are cheap and very handy to have.

Alright, I wont recommend it again. (I had no idea that was problematic for the owners).

I always install one of these screens in the upper hose on these old cars, otherwise your radiator WILL get plugged up.

LINK TO GANO UPPER HOSE SCREEN

If you're going to throw a kitchen strainer in there to plug up your hose you might as well install the proper thing.

WOW Feets, you are wrong, the set up I use works great.
Typical

that is a bypass filter, what happens to the unfiltered coolant with rust chunks to plug up the radiator.