Toyota 5S-FE (2.2L I-4) bleed cooling system

[92saturnsl2]

Just got done refurbishing a '99 Camry w/ the 2.2L 4 cylinder. Timing belt kit, water pump & housing, oil pump reseal, trans fluid change, new radiator & hoses, whole bunch of stuff done. As I prepared to fire it up (filling fluids), the coolant system has me scratching my head how the new coolant will make its way to the water pump.

New radiator, plus I used the engine block drain so I suspect the system is mostly empty. But the lower radiator hose goes straight to the thermostat, so I don't see how the coolant can enter the engine/water pump from there unless the coolant is at thermostat opening temp. The upper radiator hose goes to a manifold of sorts on the driver's side of the cylinder head, but being at the top of the radiator, can it fill the engine / give the water pump something to pump from there? The design sort of has me baffled, I'm used to the thermostat being on the upper radiator hose.

Anything I should know about initial fill / bleeding on this engine?

 

[supton]

Not really. On mine, I did drain the radiator at least 4 times (two swaps, two timing belts). All I recall doing was filling to the brim, squeeze the upper hose a few times, starting and letting idle a bit, topping off the overflow tank. Following day would need a top off on the tank.

Maybe I waited until the engine would burp on that first start, before putting on the radiator cap. Honestly I did not put much thought into it.

Don't forget, there are two hoses. As you fill, if one hose is blocked by the thermostat (I think it's got a small hole in it?), coolant can go the other way around. If you have one of the fancy funnels that seals to the radiator, you can fill above the cap line and it will run down in the top hose too.

 

[mattd]

Vacuum fill it would be easiest

 

[zzyzzx]

Anything I should know about initial fill / bleeding on this engine?

No. As long as it has the OE style thermostat in the right way (with the little hole in it) you will need to do nothing special to bleed the system.

 

[The Critic]

Vacuum fill it would be easiest

This. The cap style ones are ideal, but even the cone style ones will work well enough for this application.

 

[92saturnsl2]

I didn't think of vacuum filling, I even have that as part of my coolant pressure test kit. In the end the Lisle funnel is what did the trick, the coolant wouldn't go from the radiator to the engine on its own. I still had to squeeze the upper radiator hose at times to get it moving. I got an additional gallon in; 1-1/2 gallons total, which seems about all she'll take. Cooling fan kicks in at about 204F (measured with a scan tool) and within seconds shuts off and temp drops to 190-195F, repeat.

 

[slacktide_bitog]

I didn't think of vacuum filling, I even have that as part of my coolant pressure test kit. In the end the Lisle funnel is what did the trick, the coolant wouldn't go from the radiator to the engine on its own. I still had to squeeze the upper radiator hose at times to get it moving. I got an additional gallon in; 1-1/2 gallons total, which seems about all she'll take. Cooling fan kicks in at about 204F (measured with a scan tool) and within seconds shuts off and temp drops to 190-195F, repeat.

That total seems about right. And yeah, the Lisle coolant funnel is awesome

 

[lbhsbz]

At the dealer (in the days before the vacu-fill things), we'd pull the upper hose off the radiator and fill the block through that, then put it back on radiator and top it up. I used one of the radiator neck funnels and let it idle for a bit until one of the hoses got pretty warm, then put the cap on, top of the reservior, and send it. After it made some pressure it would burp and suck what it needed outta the reservoir, putting the level about perfect.

 

[92saturnsl2]

At the dealer (in the days before the vacu-fill things), we'd pull the upper hose off the radiator and fill the block through that, then put it back on radiator and top it up. I used one of the radiator neck funnels and let it idle for a bit until one of the hoses got pretty warm, then put the cap on, top of the reservior, and send it. After it made some pressure it would burp and suck what it needed outta the reservoir, putting the level about perfect.

It's funny you mentioned that, I seriously considered removing the upper radiator hose to fill the block from there, but the radiator was chock full and I didn't want to make a mess / waste expensive coolant. If I had to do it over again, that's the approach I'd take, or I might make an attempt at vacuum filling.

 

[michaelluscher]

The service manual doesn't have an ornate bleeding procedure
A spill free funnel or vacuum filler would probably be easier
Warming the engine, then topping off the radiator + overflow (being careful of boil over) works
Spill free funnels are under $20 now, I guess by today's standards it's a DIY essential tool

Even Toyota in training documentation for the ZZ series engines, the procedure is very simple

 

[lbhsbz]

It's funny you mentioned that, I seriously considered removing the upper radiator hose to fill the block from there, but the radiator was chock full and I didn't want to make a mess / waste expensive coolant. If I had to do it over again, that's the approach I'd take, or I might make an attempt at vacuum filling.

If the radiator is full, just push down a bit on the arch of the top hose, and it'll fill the block....slowly, with what's in the top tank. I usually do this a handful of times anyway while it's sitting there warming up.

I've sort of made a habit out of filling the block as I reassemble things...

A lot of vehicles now have the t-stat at about the lowest point in the cooling system (engine coolant level, not radiator/plumbing), so I just put the stat in and fill it from the top till it's mostly full, then hook up the rest of it and fill the radiator.

Old small block chevys and such with the stat up on top, I'd pull it, fill the engine through the hole in the intake manifold, which would also fill the radiator up to that level...install the stat/housing/upper hose, top it up, put the cap on and slam the hood. It's as full as it's gonna get at that point.