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Overheat after water pump job


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Car was running perfectly fine prior to this, I just did a tbelt/oil pump/water pump job as PM.

 

Replaced the water pump and thermostat and have burped this thing all morning long and it's still wanting to overheat. As usual the lower hose is air temperature and the upper hose is hot.

 

With the car running, radiator full, and the radiator cap off, water just won't start to flow.

 

Could I have installed the thermostat improperly?

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is it a OEM t stat?

if not, thro it away and get a OEM from the dealer

oh yes, I only use OEM t-stats. i even just boiled it to make sure it works, it does.

 

i guess i'll burp it again, i know they're difficult, but i've never had this kind of trouble burping an EJ motor.

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Gary, do you have the bleeder plug on the passenger side out? I take the plug out and fill thru the opening where the cap goes. I keep filling until fluid comes out the bleeder hole. I then run it with the cap loose until it gets to op temp (Tstat open) I take the plug back out the cap off and top it off again until fluid comes out the plug hole.

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no i didn't know there was a bleeder screw on the passengers side of the radiator. looks like this one is finally figured out, but doing the same work to my grandmothers legacy too and my wife's impreza is due as well for a thermostat so i'll be sure check that out on those.

 

i burped it again (after pulling and checking the Tstat) and finally it's back to normal. Got heat in the cabin and it's running normal temps. that's odd to me, i've done numerous EJ jobs before, did this one the same way and it was much more difficult to get all the air out. wonder what the difference was.

 

thanks guys.

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I recently had a stubborn 2.2. Someone was helping me and filled the rad and not through the top hose. I'd gotten by that way with 2.2's before but not this one. Drained and refilled through top hose cured it.

 

The 2.5's I always do throught the top hose figuring they can be tricky.

 

Between filling through the top hose and elevating the front of the car they usually burp well for me.

 

Glad it's sorted out.

 

Dave

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i recently did the radiator on my 96' EJ22 and that thing was just as stubborn...so finally i just took it up to like 6k RPMs for a second and let off...and said good bye to the air bubble....sometimes it works sometimes it doesnt....also im not sure what year this car was but the newer ones like 05+ have the heater core higher up in the dash so they love to get air pockets...we usually just raise the front of the vehicle off the ground to make sure it flows through the heater core w/ no air pockets...

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All wrong for EJ series motors.. take the top hose off the radiator, full the block full of coolant first. Then follow this procedure

 

it fills the block first (takes out the huge air pocket u get by filling through the rad). When running to ge tthe t stat to open put a big funnel in the rad cap hole so the coolant sits higher than the heater core.

 

do it this way, theres no need to let the car sit or any of that.

(I work at a radiator shop.. pro at bleeding all cooling systems :banana:)

 

 

 

 

I've never had an issue like most. Whenever you open the cooling system, remove and clean out the overflow tank.

 

1- Remove radiator cap

2- Open bleed valve in radiator

3- with engine running, add coolant SLOWLY (this allows for air to escape)

4- wait for T-stat to open (will surge fluid out the radiator)

5- SLOWLY top off fluid.

6- Fill overflow to hot line

7- Install cap, let car cool for an hour or two.

8- Check coolant level. Take car for a test drive. Watch temp gauge. Sometimes the car will run hot (will be obvious). Top off cooling system.

 

Then you are good to go.

 

nipper

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All wrong for EJ series motors.. take the top hose off the radiator, full the block full of coolant first. Then follow this procedure

 

it fills the block first (takes out the huge air pocket u get by filling through the rad). When running to ge tthe t stat to open put a big funnel in the rad cap hole so the coolant sits higher than the heater core.

 

do it this way, theres no need to let the car sit or any of that.

(I work at a radiator shop.. pro at bleeding all cooling systems :banana:)

 

Well then I've been doing it flawlessly wrong for 6 years now!:banana: Like I said I've never had a air bound issue with a soob.

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Well then I've been doing it flawlessly wrong for 6 years now!:banana: Like I said I've never had a air bound issue with a soob.
i've always thought all the burping threads were odd since i've never had a problem before today either. thing is - i work on far more subaru's than most, not just my own. so not just a handful, but dozens of different vehicles over the years and no problem. did the same thing today and it was a beast??
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The service manual says to use the bleed port, fill radiator method, but I am going to go against the majority here. The top hose method is not necessary on a normal car, with a top thermostat, but on the EJ motors, the thermostat is positioned in the lower hose. I have found with experience that the top hose fill method on a simple drain and return, allows me to put nearly every drop back into the system, presuming I then add the remainder to the radiator. Just putting the coolant in the radiator alone leaves a lot of liquid left in the bucket while the motor is idling and heating up. It takes 30 seconds to pull the top hose off the radiator and pour some liquid down into the engine, and considering the sensitivity of the EJ25’s at least to overheating, I don’t see a cause for argument here. So long as the thermostat opens before the engine overheats, there’s no advantage to backfilling the motor, but if I avoid engine overheating even once, it’s worth the moments spent. If these cooling systems are not special in any way, why does everybody here (including me) insist on using only a Subaru thermostat?

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it's not a big deal, do it anyway you want that gets the coolant out eh? i didn't do it either way and it worked. go figure.

 

If these cooling systems are not special in any way, why does everybody here (including me) insist on using only a Subaru thermostat?
compare a typical stant to a subaru t-stat. stant looks like a painted cardboard kids toy and the Subaru looks like NASA material.
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