Most times cabin heat blowing cool or just warm. Is due to low coolant level. Obstruction is less common.
OEM hose is best. Most times, I only replace the first 90 degree hose from engine DS to plastic Tee. Very import, to not, put side pressure on pipe coming up from engine (rear water bypass) this hose attached to. Doing so can result in a leak were pipe pressed into rear water bypass. I do not replaced any of the other,of the 6 hose, unless damaged or swollen. If replacing any others. Be warned, the pipes at fire wall (heater core pipes), are very thin walled aluminum. As such crush very easily.
I always place OEM clamps, back in there impression in the rubber hose, is same orientation. With the new hose I place clamp, in any orientation but same distance from end of hose all are.
Here the first 90 degree hose. I replace it, because plastic breaking off in it. Tends to fall into engine side, where I can not blow out.
Dawn dish soap and water, is recommended o-ring and hose install lube.
I avoid tap water, it will damage the coolant system. I use as Toyota recommends, distilled water as a flush medium with or without chemical flush or to mix with Toyota LL (red) 50/50 1998-03. I use compressed air ~15PSI, to back flushing. Flushing into a catch can, for inspection. If I find, my pictures of this type blowing out, I'll post them up. Meantime here's a video, in this thread below, where I use pump to back flush heater cores.
forum.ih8mud.com
Most times cabin heat blowing cool or just warm. Is due to low coolant level. Obstruction is less common.
Top coolant and bleed off air from system:
Note, of must haves:
Once system topped with coolant, while cap off. Run engine to warm up and add more coolant mixture to radiator as you see it draw down. As soon as you see coolant move/flowing, as seen while looking through top of radiator. Fill to neck and replace radiator cap. You cannot remove cap again, or hot coolant will blow out open radiator.
Run engine (short drive if you like) until at normal operating temperature. Bring RPM up to at least 3K for a few minutes. Shut down engine and park until full cool down. About 8 hours. Air, travel to high point. So, park level or even better, with front end higher than rear of vehicle. That way air pocket is at top of radiator (high point)
After complete cool down, before OAT (outside air temp) raises. Remove radiator cap and fill radiator to top and add to reservoir full line if needed.
Continue doing this each morning, until one day after no more coolant can be added to radiator.
Note coolant is very susceptible to heat expansion. As such the reservoir (expansion tank) level changes with temperature. But the radiator should also be full to the very top. Never open the radiator cap when engine hot, as coolant blows out explosively as it’s under pressure do to heat expansion of coolant. Even removing cap, in the morning after OAT begins to climb, if topped, will come out the cap area. Never remove the cap while doing this topping procedure, until full cool down and ready to top. Doing so, system will lose its vacuum created by contraction/cooling coolant.
Tip: old piece of carpet makes a nice surface to lie on.
Tip: After 8 hours or more of engine cool down. In winter level in reservoir will drop on very cool mornings. I like bring up to low line (cold line) when very cooled. In summer raise above low line, this is ok, just level it. I mark position with tape and note ambient temperatures, then keep eye on throughout the year for loss. Any loos should be investigated as to why. Remove radiator cap once and a while after cool down to check as well, it should always be full when you look in
OEM hose is best. Most times, I only replace the first 90 degree hose from engine DS to plastic Tee. Very import, to not, put side pressure on pipe coming up from engine (rear water bypass) this hose attached to. Doing so can result in a leak were pipe pressed into rear water bypass. I do not replaced any of the other,of the 6 hose, unless damaged or swollen. If replacing any others. Be warned, the pipes at fire wall (heater core pipes), are very thin walled aluminum. As such crush very easily.
I always place OEM clamps, back in there impression in the rubber hose, is same orientation. With the new hose I place clamp, in any orientation but same distance from end of hose all are.
Here the first 90 degree hose. I replace it, because plastic breaking off in it. Tends to fall into engine side, where I can not blow out.
Dawn dish soap and water, is recommended o-ring and hose install lube.
I avoid tap water, it will damage the coolant system. I use as Toyota recommends, distilled water as a flush medium with or without chemical flush or to mix with Toyota LL (red) 50/50 1998-03. I use compressed air ~15PSI, to back flushing. Flushing into a catch can, for inspection. If I find, my pictures of this type blowing out, I'll post them up. Meantime here's a video, in this thread below, where I use pump to back flush heater cores.
Scored 00LX w/557,333 Km, Emerald! No start condition. needs a ton of work. No Problem!
I've been on the look out for a fender for 3 months now, plus I need a couple interior pieces. Trust me when I say I cannot find a parts rig anywhere near Memphis. How would you inspect the slip yoke for wear or play? Just excessive movement laterally? Thanks 2001! Any play twisting or...
forum.ih8mud.com
Most times cabin heat blowing cool or just warm. Is due to low coolant level. Obstruction is less common.
Top coolant and bleed off air from system:
Note, of must haves:
- Good thermostat (OEM) properly installed jiggle valve at top, which functions as air bleeder.
- A good radiator cap (OEM).
- No obstruction in reservoir hose or its cap.
- Reservoir hose must drop straight (must not be curled) to bottom of reservoir. End of hose, must be submerged in coolant during cool down and normal operation. Or it will suck air into coolant system.
Once system topped with coolant, while cap off. Run engine to warm up and add more coolant mixture to radiator as you see it draw down. As soon as you see coolant move/flowing, as seen while looking through top of radiator. Fill to neck and replace radiator cap. You cannot remove cap again, or hot coolant will blow out open radiator.
Run engine (short drive if you like) until at normal operating temperature. Bring RPM up to at least 3K for a few minutes. Shut down engine and park until full cool down. About 8 hours. Air, travel to high point. So, park level or even better, with front end higher than rear of vehicle. That way air pocket is at top of radiator (high point)
After complete cool down, before OAT (outside air temp) raises. Remove radiator cap and fill radiator to top and add to reservoir full line if needed.
Continue doing this each morning, until one day after no more coolant can be added to radiator.
Note coolant is very susceptible to heat expansion. As such the reservoir (expansion tank) level changes with temperature. But the radiator should also be full to the very top. Never open the radiator cap when engine hot, as coolant blows out explosively as it’s under pressure do to heat expansion of coolant. Even removing cap, in the morning after OAT begins to climb, if topped, will come out the cap area. Never remove the cap while doing this topping procedure, until full cool down and ready to top. Doing so, system will lose its vacuum created by contraction/cooling coolant.
Tip: old piece of carpet makes a nice surface to lie on.
Tip: After 8 hours or more of engine cool down. In winter level in reservoir will drop on very cool mornings. I like bring up to low line (cold line) when very cooled. In summer raise above low line, this is ok, just level it. I mark position with tape and note ambient temperatures, then keep eye on throughout the year for loss. Any loos should be investigated as to why. Remove radiator cap once and a while after cool down to check as well, it should always be full when you look in
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