Pipe from radiator and enigine block

Need More Information, what is the pipe connected to
is it on the overflow tank.

That there are deposits (probably from using tap water in the coolant system instead if distilled water) which have built up. They are built up in the entire cooling system including the radiator and heater core as well as the cooling passages inside the engine. The entire system needs to be flushed...it may take multiple times to completely clean it out. Then the system needs to be refilled with coolant and distilled water

Someone has been using tap water in the radiator and the minerals have deposited. The coolant system needs to be flushed before replacing the water pump.

flush the radiator out means take it off. flush out swapping end to drain it, keep doing this until there is no rust water and runs clear. if it is red really red colour you should change the radiator. also you should flush out the internal heater as well this can be done with hose pipe swapping hose pile from one pipe in to out pipe. and just keep doing it till it is clear.. flush engine out put hose in on hole and block up other pipe that have been taken off e.g radiator and heater change side of engine until clean running water you may want to take the thermostat off and clean that out to. if and black sludge comes out it has been blocking up for awhile and not had a regular clean out. 2 to 3 years is fine with atop up of antifreeze every year.after all clean put parts back on. fill system run engine till hot keep topping up until all the air is out squeeze all accessible pipes you can and get the are out when the fan comes on. turn engine off if fan don't stop pull the fan fuse will be in the engine bay fuse box. and leave engine to cool down leaving the top off the bottle. top up when cold put in the antifreeze mix/summer mix. and one cap of strong bleach just one. this will stop it blocking up so quickly.. only one cap any more will make air in the system. should be fine after this.

Hi Eric, Before you back flush have the pressure radiator cap inspected together with the cooling fan operation. A defect there will result in over heating. To back flush, detach the cabin heater pipes and open the radiator return pipe and adjust the cabin climate control to fully hot. Attach a hose pipe so that water runs opposite to the normal circulation and turn on the flow. Afterwards when refilling remember to open the air bleeder, replace coolant and run water into the system until all air is expelled from the system. Close up and test run. Keep in mind that air in the cooling system will also cause overheating. Regards John

I Have a 94 Rodeo,3.2l v6 I had the same problem...Yes it is a drain hole..You might have a coolant pipe running under your lower intake if so it's the "O" ring on that pipe..It runs from the upper radiator hose to rear of block...50 cent part. If you are doing it yourself check the other heater hose metal pipe O ring also. towards the front under the thermostat housing. I just fixed mine.I had antifreeze coming out the inspection plates on the trans took off the upper plenium and lower intake and the rubber O ring was shot.Clean out flange use a wire V shaped wheel. make sure the Ring fits Snug on the coolant pipe,dry fit in the flange.( Got assorted sizes at NAPA) put a good coat of Black RTV silicon on O ring,And some in the hole itself press pipe in hole and install the bolts.Allow to set for 3hrs. Again this is on a 94 Isuzu Rodeo 3.2 L V6 5spd. Hope that helps you

IF YOU SEE WATER PUMP WEEP HOLE LEAKING COOLANT.RADIATOR AND ENGINE BLOCK NEEDS FLUSHING.A FAULTY EGR VALVE WILL MAKE CAR OVERHEAT.HAVE VECHICLE SCANNED FOR EGR VALVE FAULT CODE MAKE SURE EGR VALVE PIPE NOT STOPPED UP WITH CARBON AND EGR VALVE STILL CONNECTED.

follow the bottom pipe of the radiator to the engine block. the thermostat is close to that.

a good idea would be to flush your system (get a bottle radiotor flush from a motor spares shop and follow instructions. It makes sense since you are going to be draining the system anyways and clearly you have an overheating problem so you are killing two birds with one stone

make sure the engine is off and cooled down. Hot radiator fluid is higher than boiling point.

remove the cooling system cap to ensure there is no pressure in the system.

loosen the hose clamps of the above mentioned pipe. remove pipe, from engine block and radiator.

Look for bolts on and close to where the radiator hose connects. there should be two ir three.

Loosen and remove. gently remove the housing. Be careful when removing the old thermostat and new thermostats do not come with the rubber seal you see around the thermo.

Replace with identical thermo. when replacing the housing remember to apply gasket sealant. this takes 8 to 12 hours to harden / cure.

replace the radiator hose to be one the safe side. tighten clamps, fill up radiator with anti-freeze/summer coolant and water.

You should be up and running in a day or two

CHECK THE HIGHT OF THE HEATER MATRIX IN THE CAB , IF ITS HIGHER THAN THE FILLER/EXPANSION TANK. THEN ITS AN AIR LOCK, LOOK FOR THE HIGHEST PIPE AND SEE IF THERE IS A BLEED VALVE, IF NOT TAKE BOTH PIPES OFF THE MATRIX FEEDS AND FLUSH OUT TO SEE IF IT IS BLOCKED, AND RECONNECT LOWEST PIPE FIRST AND FILL SYSTYM TILL WATER APPEAR FROM TOP AND RECONNECT RUN MOTOR, AND KEEP TOPIN UP.

2.4 enigine is the harder of the 3 enignes. it will need a timing chain to be removed and a coolant tube in the back of the engine to be removed. this job on the book calls for almost 7 hours.

if its 3.3 or 3100 its alot easier.

3100 is just 4 10mm pulley bolts and 5 or 6 small 8mm water pump bolts.

3.3 is alittle more work, but same concept as 3100 engine. more owkr only cause its in a tighter area.

good luck,
michael