BRZ overheating

[Notso]

Originally Posted by mav1178

Wow... you didn't even wait for a reply.

Again: I ask why you think it's overheating. I am not speculating on leak source, I am asking why you think it's overheating and how it is diagnosed. If you can't describe how you reached the overheating conclusion, you aren't telling us the whole story and no one can help you, not even Subaru.

Leaks in the coolant system are from any of these sources:

- heater core
- radiator
- hoses
- leaking head gasket
- water pump
- radiator cap


Overheating is from any of the following:
- actual overheating
- air trapped in system
- bad radiator cap
- leaks
- faulty coolant temp sensors

If you are having an overheating issue but you can run the engine with no visible leaks, then you simply need to bleed the system better.

Best $25 you'll ever spend:
Amazon.com: Lisle 24680 Spill-Free Funnel: Automotive

-alex

Sorry, when i said "around here" i meant the auto shops in Boise, sorry for the misunderstanding. I appreciate everyone on this forum. I'm not sure what your asking about as far as diagnosis. other than it says it's running really hot. It redlined to "h" the other day and the check engine light came on, so i turned off the car and coasted the rest of the way home, obvious smell of coolant, hood is extremely hot to the touch after driving 5 miles etc... I did bleed the system, maybe I need to do it again/better, but that still doesn't solve the leaking problem.... it's leaking right around the thermostat housing which the waterpump is directly above it, so i'm thinking waterpump? all the hoses around there look good

[Notso]

Originally Posted by WolfpackS2k

FYI in the future I'd strongly urge not letting a car sit for an entire year unused. That's hell on the car. I understand your license was suspended but ask a friend to drive it around every once in a while (if that ever happens again).

I'd also recommend lifting the car a little bit; otherwise it sounds like no shop will ever work on your car in the future.

it's funny, I wouldn't let anybody drive it, including my gf that lives with me because it is so damn low, if you don't take a speed bump at the wrong angle boom... and I have been looking into some spring rubbers to bump it back up around an inch

[Bowen]

Originally Posted by Notso

it's funny, I wouldn't let anybody drive it, including my gf that lives with me because it is so damn low, if you don't take a speed bump at the wrong angle boom... and I have been looking into some spring rubbers to bump it back up around an inch

Lowered on springs?

[Notso]

Originally Posted by Bowen

Lowered on springs?

yes

[86kahl]

@Notso Rent a coolant pressure tester and take it up to 1.3bar, and start looking. Once the system is leak free, put the drivers side front up on a jack stand so the thermostat is at a higher point, run the car with the rad cap off and the tool Mav1178 suggested installed and filled with coolant, run it for about 20mins or until the lower rad hose is warm, turn on the heater full blast and let it run for another 30mins or longer. You should see bubbles, that's a good sign.

[mav1178]

Originally Posted by Notso

Sorry, when i said "around here" i meant the auto shops in Boise, sorry for the misunderstanding. I appreciate everyone on this forum. I'm not sure what your asking about as far as diagnosis. other than it says it's running really hot. It redlined to "h" the other day and the check engine light came on, so i turned off the car and coasted the rest of the way home, obvious smell of coolant, hood is extremely hot to the touch after driving 5 miles etc... I did bleed the system, maybe I need to do it again/better, but that still doesn't solve the leaking problem.... it's leaking right around the thermostat housing which the waterpump is directly above it, so i'm thinking waterpump? all the hoses around there look good

If you continue to drive the car in this fashion, you will need a new motor soon.

I ask about diagnosis because overheating is caused by simple things. I am assuming when the car was in storage, it was operated from time to time to keep things properly lubricated... we can assume the water pump is leaking from what you are saying, but if a qualified mechanic can't find a leak, then 1) they are giving you BS, or 2) you don't actually have a leak from the water pump.

At this point, your coolant system needs to be pressure tested before any other assumptions are made.

-alex

[Notso]

Originally Posted by mav1178

If you continue to drive the car in this fashion, you will need a new motor soon.

I ask about diagnosis because overheating is caused by simple things. I am assuming when the car was in storage, it was operated from time to time to keep things properly lubricated... we can assume the water pump is leaking from what you are saying, but if a qualified mechanic can't find a leak, then 1) they are giving you BS, or 2) you don't actually have a leak from the water pump.

At this point, your coolant system needs to be pressure tested before any other assumptions are made.

-alex

It hasn't been driven since i tested it with the thermostat being taken out. and a mechanic hasn't been able to find a leak, because no one is willing/able to get it on a car jack to look at it. thats why I came here, to gather info and do it myself, but i know there is a leak, i cleaned the skidplate before i put it back on. nothing leaks when it's sitting, but when i last drove it around the block there was blue coolant (not a lot) but some sitting on the skidplate just under the thermostat housing and water pump. I'll pressure test it when i get back in town on Monday. Whats the diagnosis if it's not up to preasure? the pump? Thanks again Alex, I appreciate your input

[mav1178]

Originally Posted by Notso

I'll pressure test it when i get back in town on Monday. Whats the diagnosis if it's not up to preasure? the pump? Thanks again Alex, I appreciate your input

Pressure testing your system for a leak is not measuring pressure. It's introducing pressure to your coolant system to simulate the conditions under which it may leak (higher temps, coolant boiling over, air pockets, etc that add pressure to a closed cooling system)

You really should look up how this type of testing is done, there's plenty of documented sources online.

-alex

[extrashaky]

Originally Posted by Notso

,,, but i know there is a leak, i cleaned the skidplate before i put it back on. nothing leaks when it's sitting, but when i last drove it around the block there was blue coolant (not a lot) but some sitting on the skidplate just under the thermostat housing and water pump.

I think this is being made more complicated than it needs to be. If you know there's a leak, you already know that a pressure test is going to fail, because you have a leak. There's really no point in doing a pressure test when you can see the visual evidence of an active leak.

If you know you have a leak, the logical next step is to find the source of the leak. That involves a very special technique professionals call noggin pokin'. The way you do this is to poke your noggin in there and see with your own eyes what's happening. You already have a general idea of where the coolant is coming from, so you already know where to start pokin' your noggin.

The water pumps on most cars have a weep hole somewhere on the bottom side to allow coolant to escape when the water pump is failing. You'll probably have to look at it from underneath to see it, but you might also be able to get a mirror or inspection camera in there instead. That's where I would start. Even if it turns out not to be coming from the weep hole, you already need to poke your noggin in there to find that leak anyway.

Fix the obvious (the leak) first and see if that stops your overheating issue. If not, move on to the next potential cause.

[justatroll]

Originally Posted by extrashaky

I think this is being made more complicated than it needs to be. If you know there's a leak, you already know that a pressure test is going to fail, because you have a leak. There's really no point in doing a pressure test when you can see the visual evidence of an active leak.

A pressure test is to help you find the leak without having to get it to temperature to pressurize the system. It is harder to work on a hot engine and if you want to unhook a hose you will have to wait for it to cool all the way down. With a pressure tester you can pressurize/relieve as many times as you want without running the engine.

Originally Posted by extrashaky

If you know you have a leak, the logical next step is to find the source of the leak. That involves a very special technique professionals call noggin pokin'. The way you do this is to poke your noggin in there and see with your own eyes what's happening. You already have a general idea of where the coolant is coming from, so you already know where to start pokin' your noggin.

Are you going to stick your head down the front of a running FA20???
Oh wait what other way might you get the system pressurized other than running the engine?

Originally Posted by extrashaky

The water pumps on most cars have a weep hole somewhere on the bottom side to allow coolant to escape when the water pump is failing. You'll probably have to look at it from underneath to see it, but you might also be able to get a mirror or inspection camera in there instead. That's where I would start. Even if it turns out not to be coming from the weep hole, you already need to poke your noggin in there to find that leak anyway.

Fix the obvious (the leak) first and see if that stops your overheating issue. If not, move on to the next potential cause.

The weep hole on a water pump will tell you when the shaft bearing/seal is failing. It will not tell you if it is pumping.

You can use your cellphone as an inspection camera and you can stick it in places you probably wouldnt put your head.
There are even apps where you can use one phone as a wifi camera and another for the display. Like a wireless inspection camera.

[tofurun]

Originally Posted by 86kahl

$10 says it's a weeping waterpump

Ill throw another 10$ at the waterpump. Just what it sounds like to me if you "tested" the thermostat. For future though to save some money drain the system leave the thermostat out temporarily and run distilled water in it to save on the coolant money till you fix the problem. when its fixed throw everything back in how it should be. Just my opinion.

[mav1178]

Originally Posted by extrashaky

I think this is being made more complicated than it needs to be. If you know there's a leak, you already know that a pressure test is going to fail, because you have a leak. There's really no point in doing a pressure test when you can see the visual evidence of an active leak.

Part of the problem is that OP isn't diagnosing it properly. It obviously leaks when it's hot, but when it's just normal idle it doesn't.

Stupid mechanics don't help either.

[Notso]

Originally Posted by mav1178

Part of the problem is that OP isn't diagnosing it properly. It obviously leaks when it's hot, but when it's just normal idle it doesn't.

Stupid mechanics don't help either.

right, which is why i came here, to figure out how to diagnose/fix it. a lot of people have mentioned a pressure test, just watched some videos on it and i should be able to find the leak under pressure. i'll report back my findings when it's done

[mav1178]

Originally Posted by Notso

right, which is why i came here, to figure out how to diagnose/fix it. a lot of people have mentioned a pressure test, just watched some videos on it and i should be able to find the leak under pressure. i'll report back my findings when it's done

BTW the stock radiator cap is 1.2 or 1.3 Bar. You should pressurize the system up to that point (or close) and it should be able to show leaking from wherever it may be.
Thermostat temp doesn't matter as the cooling system will be pressurized on both sides of the thermostat.

-alex