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Discussion Starter · #21 ·
so no luck with anyone knowing where these wires go opposite the ecu i rhought i found rhem in the frunk but just earily simular i think i was doin something else so probly did not give it the attention it deserved. also still over heating or boiling over if it relatively cool out side and i keep the load low babying her i can ride but soon as i jump on her evwn a little that idle starts to jump up and Down at which point ive been opening valve on radiator ans lettin coolant boil out for a second but when i open that valve i hear a little blast of air i just cant really tell if its suckin in because the system has gone into vacumm or if its out. not destinctive enough. but after a few seconds the idle will mellow out still not seeing any irregularities with the coolant or oil. how would it behave if i removed the t stat entirely id assume that would be a good way to evaluate further . and last thing if i used all distilled water and no coolant or antifreeze what could i expect it to do
 

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The stat is what is known as a dual-poppet which controls the bypass loop along with the radiator circuit. Do not remove it! removing it will actually reduce your ability to cool the engine because the bypass circuit will never close when you want it to (at peak load and engine temps).
 

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so no luck with anyone knowing where these wires go opposite the ecu i rhought i found rhem in the frunk but just earily simular i think i was doin something else so probly did not give it the attention it deserved. also still over heating or boiling over if it relatively cool out side and i keep the load low babying her i can ride but soon as i jump on her evwn a little that idle starts to jump up and Down at which point ive been opening valve on radiator ans lettin coolant boil out for a second but when i open that valve i hear a little blast of air i just cant really tell if its suckin in because the system has gone into vacumm or if its out. not destinctive enough. but after a few seconds the idle will mellow out still not seeing any irregularities with the coolant or oil. how would it behave if i removed the t stat entirely id assume that would be a good way to evaluate further . and last thing if i used all distilled water and no coolant or antifreeze what could i expect it to do
pure water will start rapid corrosion throughout the cooling system and reduce the life of the water pump seal (coolant helps lubricate the ceramic face0seal).
 

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If multiple bleeding (by the book) isn't helping and you still have the problem with coolant blowing out the fill tank, you either have a bad water pump (unlikely), a bad thermostat (possible) or a leaking head gasket (likely from your description).
Dave
 

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Discussion Starter · #25 ·
If multiple bleeding (by the book) isn't helping and you still have the problem with coolant blowing out the fill tank, you either have a bad water pump (unlikely), a bad thermostat (possible) or a leaking head gasket (likely from your description).
Dave
thanks dave im slowly coming to the realization that that must be the case sadly with less than a thousand miles since rebuild really blows.
 

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Discussion Starter · #26 ·
whats gonna be the sure fire way to know for sure dave i did just change t stat but not with toyota but going to go to toyota today and see if i can find one then a leak down test and likely check the compression. i have read here th hg can be rather elusive
 

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whats gonna be the sure fire way to know for sure dave i did just change t stat but not with toyota but going to go to toyota today and see if i can find one then a leak down test and likely check the compression. i have read here th hg can be rather elusive
there are coolant chemical tests kits to check for the presence of combustion gasses in the coolant. A leakdown tester, done on a warm engine might show bubbles in the coolant, but it might not because the leakdown test only applies a fraction of the peak combustion pressure. The final determination is that if you have a known good pump and stat, and the cooling system is filled; when the coolant tank overflows after about a minute of high load, then it must be the head gasket.

Dave
 

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Discussion Starter · #28 ·
there are coolant chemical tests kits to check for the presence of combustion gasses in the coolant. A leakdown tester, done on a warm engine might show bubbles in the coolant, but it might not because the leakdown test only applies a fraction of the peak combustion pressure. The final determination is that if you have a known good pump and stat, and the cooling system is filled; when the coolant tank overflows after about a minute of high load, then it must be the head gasket.

Dave
i pulled the radiator today and as best i could tried to flush it out and i got some promising developments although in the end i think the radiator needs replacing only left to do after that will be assume its the head gasket. after flushing today i saw improvments a really big peice of i dont know what anout the size of a golf ball maybe just a tad smaller. years ago before i parked her and did the rebuild i recall trying to use some head sealer crap ( this was before i knew better obviously) it almost appears to me to be remnantz of that stuff in the radiator i used two types that i can remember k12 and blue devil liquid glass that was a little over seven years ago. With any luck its not traveled through the entire system now after rebuild clogging it all over again. i am almost certain its the radiator that needs replacing definately surges in the cooling system when i apply a good amount of load on it driving i see the temp guage go way down and then slowly creep back up and if hit the gas a littld harder i see it go down a bit quite a bit actually. head gasket is the final option so im leave it for the fjnal fix if its needed may be wishful thinkjn but there is no oil in the coolant and vice versa and with all this biz of overheating everythjng else has had to made as close to perfect ie timing idle plugs wires blah blah anytjing at all that may cause it to over heat has been dialed in its got great power though i think my tvis is acting up a bit probly jealous cuz all tge attsntion the cooling system is getting. so new radiator any suggestions on unit to purchase?
 

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My only replacement recommendation is make sure that the replacement has the same venting feature that the OEM does, so you can get all the air out. Some of the Spyder aftermarket radiators have not purge feature and they are almost impossible to purge of air.
 

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years ago before i parked her and did the rebuild i recall trying to use some head sealer crap...

... i am almost certain its the radiator that needs replacing definately surges in the cooling system when i apply a good amount of load on it...

... driving i see the temp guage go way down and then slowly creep back up and if hit the gas a littld harder i see it go down a bit quite a bit actually....

head gasket is the final option so im leave it for the fjnal fix if its needed may be wishful thinkjn but there is no oil in the coolant and vice versa and with all this biz of overheating everythjng else has had to made as close to perfect ie timing idle plugs wires blah blah anytjing at all that may cause it to over heat has been dialed in its got great power though i think my tvis is acting up a bit probly jealous cuz all tge attsntion the cooling system is getting. so new radiator any suggestions on unit to purchase?
Are you trying to tell us that you put stuff on your head gasket last time you assembled the engine?

What makes you think that you need a radiator? The simplest test for a radiator is whether it gets hot. If the radiator gets hot and has airflow, then it is not the problem. What do you mean by "surges in the cooling system?" Remember that we are not mind readers, and you have to describe what is happening.

Is this happening just after the engine warms up, or does this also happen after you have been driving for many miles? This is important because the temperature will often drop sharply when the thermostat first opens. Once the coolant in the radiator loop has mixed in, then it won't happen again.

Reading your posts is a headache, literally. Here is some advice:
1. Write in sentences.
2. Don't ramble so that everything gets mixed together. Finish one thought before you start on another.
3. If you can't edit what you write to make it into English, then keep it simple. Just the facts.
 

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Discussion Starter · #31 ·
t

ok so when i stop the car at a stoplight it heats up when i drive if i drive right it cools back down in an incredibly rate. The reflects that fast rate. maybe im just an ass but only way i can describe that scenario is surges in the cooling system
 

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Discussion Starter · #32 ·
Im no guru like some of the greats here that why i come to learn but im fairly certain of one thing my car keeps over heating that im certain of. Everything else not so much ok so i believe i need a new radiator due to having done all else i can do which certainly wouldnt be all but all i know
Correct timing
Have bled coolant by the book
Replaced plugs and wires
Flushed radiator and discovered golf ball sized glob in their of what looks like head sealer
Because years ago i reckon i used that head sealer and there was some still in the radiator because prior to the build i did not flush radiator before reinstallingi just pust the hoses on and filled her up not thinking at all hindsight always. Anyway i think that **** is still in the radiator.
moving on i replaced the filler cap with a 13psi rating
I switched the two hoses around on the overflow just in cAse i had them reversed i have read about a couple people having problems.
see i dont have facilities to work on my car so i gotta do what i can when i can how i can so there has been no leakdown test done or chemical tests no pressures test no actual real data has been gathered but…….before looking at the water pump then last the head gasket i can easily swap out the radiator and qui kly mind you and i can pick up for about 150. See if i do that its a win win sure i may not know all the ways i got there but if changing the radiator fixes it then great and if not thats ok too because this one without doubt needs replacing
And that is why i think i need a new radiator but but i am very open minded veryw
 

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Discussion Starter · #33 ·
Well have an advil man im sorry if my grammar offends you truly i am i think it all , but doesnt come out the same and dont like typing if it gives you a headache i suggest not reading my threads because i dont want to give you a head ache ill try to write a lil beddar whens i is scribing my problems. Might seem ungrateful but my gratitude really goes deep with you guys just freaking teach me about the car
 

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If your main problem is that the temp rises when you stop the car (like in traffic) and the temp returns to normal when you get moving, you radiator is fine, but your radiator fans are not coming on. There is a procedure to check out the electric circuits for the fan(s) in the shop manual, though you should probably check the fuse for the fan first.
Dave
 

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Discussion Starter · #35 ·
Are you trying to tell us that you put stuff on your head gasket last time you assembled the engine?

What makes you think that you need a radiator? The simplest test for a radiator is whether it gets hot. If the radiator gets hot and has airflow, then it is not the problem. What do you mean by "surges in the cooling system?" Remember that we are not mind readers, and you have to describe what is happening.

Is this happening just after the engine warms up, or does this also happen after you have been driving for many miles? This is important because the temperature will often drop sharply when the thermostat first opens. Once the coolant in the radiator loop has mixed in, then it won't happen again.

Reading your posts is a headache, literally. Here is some advice:
1. Write in sentences.
2. Don't ramble so that everything gets mixed together. Finish one thought before you start on another.
3. If you can't edit what you write to make it into English, then keep it simple. Just the facts.
The stat is what is known as a dual-poppet which controls the bypass loop along with the radiator circuit. Do not remove it! removing it will actually reduce your ability to cool the engine because the bypass circuit will never close when you want it to (at peak load and engine temps
id like if you could elaborate a little please
 

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Discussion Starter · #36 ·
If multiple bleeding (by the book) isn't helping and you still have the problem with coolant blowing out the fill tank, you either have a bad water pump (unlikely), a bad thermostat (possible) or a leaking head gasket (likely from your description).
Dave
so bought and installed after market radiator seems identical sensor after removing and installing on new only big difference is the bleed valve they are there seem to me to be about the same size without using calipers or anything only difference is just a thread butterfly type of plug and i did not see an easy way of using the old valves on the new radiator pthey did not appear to my untrained eye to be removable so can i buy them somewhere ? yes pleaze tell me where and what you reccomend.
 

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Discussion Starter · #37 ·
If your main problem is that the temp rises when you stop the car (like in traffic) and the temp returns to normal when you get moving, you radiator is fine, but your radiator fans are not coming on. There is a procedure to check out the electric circuits for the fan(s) in the shop manual, though you should probably check the fuse for the fan first.
Dave
thanks dave i have indeed done all that they come on and function normally
 

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id like if you could elaborate a little please
Every modern engine has 2 circuits for coolant. One is the bypass circuit that circulates coolant through the engine and the heater core. The heater core always has coolant flowing through it, even when there is no demand for heat. If you have an oil cooler and a little circuit to prevent the throttle body from icing up in cold weather, they flow in-parallel to the heater core. Also the coolant fill-tank is in the bypass circuit and is there to allow for expansion and de-aeration of the cooling system (any bubbles of air or steam that go in the top of the tank get separated in the tank and only liquid gets returned to the engine. When you start a cold engine this bypass circuit allows a good amount of coolant to flow throughout the engine to let the engine to warm up evenly and limits thermal stress in the hottest parts of the engine (like around the exhaust valve seats. The other circuit is the radiator circuit with a path that includes the whole engine, coolant pump and the radiator, The dual-poppet thermostat controls the flow between the radiator circuit and the bypass circuit. It completely closes the radiator circuit when the engine is cold (to minimize warm-up time) and completely closes the bypass circuit when things are very hot to maximize the coolant flow to the radiator. If you run with no stat, the bypass circuit acts like a partial short-circuit to the radiator circuit, because the pump can only move a certain amount of coolant. Hope this helps!

Dave
 

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Discussion Starter · #39 ·
Every modern engine has 2 circuits for coolant. One is the bypass circuit that circulates coolant through the engine and the heater core. The heater core always has coolant flowing through it, even when there is no demand for heat. If you have an oil cooler and a little circuit to prevent the throttle body from icing up in cold weather, they flow in-parallel to the heater core. Also the coolant fill-tank is in the bypass circuit and is there to allow for expansion and de-aeration of the cooling system (any bubbles of air or steam that go in the top of the tank get separated in the tank and only liquid gets returned to the engine. When you start a cold engine this bypass circuit allows a good amount of coolant to flow throughout the engine to let the engine to warm up evenly and limits thermal stress in the hottest parts of the engine (like around the exhaust valve seats. The other circuit is the radiator circuit with a path that includes the whole engine, coolant pump and the radiator, The dual-poppet thermostat controls the flow between the radiator circuit and the bypass circuit. It completely closes the radiator circuit when the engine is cold (to minimize warm-up time) and completely closes the bypass circuit when things are very hot to maximize the coolant flow to the radiator. If you run with no stat, the bypass circuit acts like a partial short-circuit to the radiator circuit, because the pump can only move a certain amount of coolant. Hope this helps!

Dave
im ztill a little unclear about the absence of the tstat i get that potentially the motor may not reach optimal temperature hence optimal running conditions but with our cooling system so overdone as is often stated here what can we assume if the temp stills climbs to boiling and finally overheats. i did manage to pull a very large air pocket off of the engine bleeder that is sbove tstat housing and tbat helped immensely but i tbe end it still ovefheated on me. dave i guess the best question i could ask is this, at what point while suffering so and so symtoms caln i be absolutely sure its the head gasket despite no oil i1n coolant and vice versa no noticable dropin compression and no power loss complications at what point do i just say yup thats the head gasket whats onw thing i can find that holds true always with the hg and is a dead giveaway if there is one at all
 

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My point about the stat, is that if you remove it you reduce that maximum flow the pump can force through the radiator, because it short-circuits in the empty stat housing. This will not cause overheating at low power levels, but is likely to at high power levels. I suspect that you head gasket is leaking between the cylinder sealing ring (fire-ring) and the cooling jacket. This will not result in any oil in the coolant and is not an unusual failure. There are 2 things you can do now: 1) get a test kit to test for traces of exhaust gas in the coolant. If it is positive, you have your answer. If it is negative, you still might have a head gasket problem because the tests are not that sensitive. 2) Go over the procedure in the shop manual for system fill and bleeding. Follow this exactly, with the engine off, the car level, and take your time slowly filling. Take it for a short drive to get it up to normal temp without going above moderate power level. After the system thoroughly cools off, recheck and/or adjust the coolant level in the tank. You now have a full system with not air bubbles if it didn't overheat on the short drive. If at this point you can drive easy without overheating, but the system overflows when driven hard, you have a head gasket leak.

Dave
 
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