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96 OBW 2.5 108k

 

I am worried about a possible air pocket somewhere in the coolant system (no symptoms, but still worried). It sounds like if there's a chance of having an air pocket, it NEEDS to be removed, or the HG will blow.

 

I could do the burp on my own, but I would much rather have a subaru master help me with it, so I can be sure the air is out.

 

Is there anyone in the Beaverton area that could help me out? How much would it cost to have someone do it for me? I'm not technically challenged, I just want to be SURE that I don't have an air pocket near the HG.

 

Thank you for the help.

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I'm NOT a master but this worked for me and I did have an air bubble. But I took off the TStat housing and hooked a garden hose to the top of the engine and flushed it out and put everything back together. When I just drained the radiator previously I didn't have any problem.

The shop guy told me to just leave the radiator cap off and run the engine for a long time 15-20 min monitoring the fluid level and toping off as necessary. I did the hose squeeze thing but the bottom hose was still pretty cool so I knew things were not flowing properly. Once the hot water worked its way down to the Tsat and it opened the bubbles released. I think as long as the cap is off bubbles will move around easier. Like I said I'm Not a mechanic. But it worked for me.

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So I should park the car on a steep uphill slope, remove the rad cap, start the engine, run it with the heat on...

do i rev the engine during the process? should the reservoir be open as well?

Do I need to add coolant as I do this?

and what is the hose squeezing trick? I have not heard of this yet (i don't think...)

 

Thanks for the help.

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Try this:

 

Having replaced coolant on my boxers many times, I have been searching for the right way to get all the old fluid out and getting as much new fluid in, without having to burp the system for a week after I'm done. I think I have finally cracked it!

 

Draining

 

Drain the radiator as far as possible with the little "faucett", and then detach the lower hose from the radiator. (If you are like me, replace any coolant hoses that you remove, and use stainless steel clamps on the new ones)

Even more fluid will drain from the radiator, and some will drain from the engine block. Detach the upper hose from the radiator, and run clean water through the rad until it comes out of the bottom clear in color.

 

Now, I do not contest that the best way to flush the engine block is by unscrewing the two drain plugs, but these are often seized and could turn into a source of trouble if you strip the threads or if they won't seal tight when you screw them back in. SO, I jack up the rear of the car until the engine block is tilting slight forward, ie. wheels about 6 inches off the ground, unscrew the thermostat housing, and let the old fluid run out through the thermostat opening. (Needless to say, I replace the thermostat gasket)

Run clean water in through the upper hose until clear water comes out of the thermostat opening. Leave the car in this position until it stops dripping water.

 

Remove the expansion tank and flush it, there will be plenty of "snot" in the bottom of it! Rinse the hose too. Install the tank again and fill to the FULL mark.

 

 

Filling

 

Close up the bottom end of the cooling system, ie. thermostat and lower hose. If possible, perform the next phase on a slight incline, car pointing upward.

Get a funnel with about 10 inches of half-inch diameter hose on the end of it and slide this down the upper hose in toward the engine block. I do this because bending the upper rad hose causes it to collapse and that makes pouring coolant into it impossible. Pour your preferred coolant directly into the engine block. Pouring slowly, and pausing along the way will help keep air from being trapped inside the block. It should swallow at about two litres before it starts to rise and threaten to come out of the hose. At that point, attach the upper hose to the rad and continue to fill slowly through the rad cap hole. Once it seems full, start the engine, let it run for twenty seconds and shut it off again. This will dislodge the few air pockets that are unavoidable and the fluid level in the radiator should drop a little after the burp, top it off.

Start the engine again, and let it run until the radiator fan starts running, be patient! When then fan starts running, top off the level in the rad and install the radiator cap - and bleed screw if there is one. During the warm up, a small amount of coolant will spill over the rad filler neck, have a cloth to absorb it.

 

Take the car for a shortish run, just a few miles to get it fully warmed up, and park it on level ground. Check hoses for leaks of course, and let it cool. This will take a number of hours, overnight is good.

In the morning, note the level in the expansion tank, it will probably be a little lower than FULL. Fill to the FULL mark, and you're all set.

 

Obviously, you should check the level in the expansion tank for a few days afterward, but there shouldn't be any problems. Resist the temptation to open the rad cap, this will only interfere

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i dont know i never had a problem.Fill the cooling system with the car off. Start the car with the cap off and waited untill the thermostat opened up. Then i would slowly fill the radiator with a premix. In 5 subarus, i've never had an air pocket.

 

 

nipper

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This is for replacing coolant. What I've always done on all my Subarus, even the old ones.

1. Open rad cap and start garden hose at low pressure.

2. open bleed valve and adjust flow so that water is going in the system at the same rate as it is exiting, e.g., the rad doesn't drop or over flow.

3. Start engine and with heater on, let it idle for at least two beers, drunk at a relaxed pace.

4. Turn off heater and engine, shut drain plug and remove hose.

5. Open draincock very slightly and as water drains add a gallon of anti-freeze at the same rate. Clean out the overflow while you are doing this stuff, so you keep your hair and hands out of the fan and belts while engine is running.

6. Shut draincock again, and restart engine and heater for another beers worth of idling, rad cap off.

Recap and drive for two years ... repeat.

 

To add to this ... it's what I learned far too many years ago dealing with Ford Flathead V-8's which were prone to blowing HGs and cracking heads. And regular vapor-locking ... but that's another story.

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This is for replacing coolant. What I've always done on all my Subarus, even the old ones.

1. Open rad cap and start garden hose at low pressure.

2. open bleed valve and adjust flow so that water is going in the system at the same rate as it is exiting, e.g., the rad doesn't drop or over flow.

3. Start engine and with heater on, let it idle for at least two beers, drunk at a relaxed pace.

4. Turn off heater and engine, shut drain plug and remove hose.

5. Open draincock very slightly and as water drains add a gallon of anti-freeze at the same rate. Clean out the overflow while you are doing this stuff, so you keep your hair and hands out of the fan and belts while engine is running.

6. Shut draincock again, and restart engine and heater for another beers worth of idling, rad cap off.

Recap and drive for two years ... repeat.

 

 

but i dont drink beer ....... so one beer is how many cocktails :)

 

 

nipper

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