overheating, bubbles, no heat, new parts

[Brian75x]

I am looking to buy an 03 Protege 5, so I am brand new to this forum. I went to look at it today, but it is overheating. I have taken the time to search and read several posts regarding the overheating. From what I can tell, the head gasket may be blown, but if I am (or actually the seller is) VERY lucky, then it may just need to be "burped."

Here are the symptoms:
1) Runs normal temp at idle, overheats quickly when driving even a mile or so.
2) Bubbles in coolant reservoir -- even at idle
3) No heat (blows cold air)

According to the seller, here is what has been done, some by garage, some by owner/friend:
1) New Tstat
2) New Tstat housing
3) New temperature sending unit
4) New water pump
5) New radiator
6) New rad cap

I did verify that both electric fans work. Running the A/C seemed to cool the engine a little bit while test driving. We only went about a mile due to the temperature rising.

It seems like most of the signs point to the head gasket, except for the lack of heat. That, to me, would point back to a stuck-closed thermostat or a clog or a bubble in the heater core. Could I get that lucky? Or is it definitely a head gasket? I did not check for white residue on the top of the dipstick.
If you think it IS the head gasket, I guess I could ask the owner if I can put the color-changing test liquid in the coolant reservoir. Are there any other sure fire tests I can do myself quickly on someone else's car?

Sorry for the "overheat repost," but hopefully I supplied enough information that this can be resolved without wasting much of your time!

 

[hat1018]

If it has no heat, that tells me there is air in the system and needs burped. Start there and cross your fingers. Good luck!

 

[xxxmonoxidechil]

^
thats the first thing id be checking also. seems like its either really low on coolant, or has an air lock in the system, and needs to be burped.

 

[Jordysoso]

Take it for a test drive, when you get outta sight, pull over and burp it see if that works. If not it's head gasket. OR.... you can get them to come down with a blown head gasket argument, and then diagnose it accordingly.

 

[Installshield 2]

yeah, if there is no heat coming into the cabin...start by getting the air out of the system.

the crappy part is there is no quick way to do it. When the car is 'warm', but not hot (let it idle up to normal temp then let it sit for 10 minutes or so), get the rear of the car as high as possible, and keep the temp setting on all the way in the red. Carefully remove the rad cap with a big dry towel wrapped around your hand/wrist. Slowly turn it to where you'll hear some hissing, then step back for a minute or so (this may not happen if the system isn't building pressure properly). Drain the radiator and flush it with water, and remain cautious as the coolant will probably be very warm still. (distilled if you're really concerned, but its going right out the bottom anyway). Disconnect the over flow reservoir from the top of the radiator (by the pressure cap) and drain that also.

So now, assuming the engine is cooled and therefor the thermostat has closed, tighten the radiator drain plug at the bottom, fill up the radiator and enough to the 'low' line in the reservoir with pre-mixed 50/50 prestone. If you want to do the mixing yourself, go right ahead, but it will get very tricky keeping the balance right when you don't know how much coolant is still currently in the system. Fill up the radiator, leave the cap off, and lower the rear of the car (this puts the radiator cap at the high point of the system, allowing air to immediately escape. This will also keep a good collection of coolant at the lower radiator line to the water pump. Now close the temp setting to 'cold' Let the engine idle up to normal operating temp, and add more coolant at the radiator cap as needed (it will go down noticeably as the thermostat opens). Try not to let the reservoir empty also, but this usually won't happen with the rad cap off as there is no vacuum to draw coolant in from that. Once normal temp is attained from idle, open the heater core by turning the setting back to the red area. Add more coolant as necessary as the heater core will draw in more coolant when opened.

For a proper full flush you'll need to do this 2 or even 3 times. The capacity of the protege is 7.9 Liters of coolant. You can do this with only water, but again, unless you are actively measuring whats coming out and know how much you are starting with...its difficult to get the mixture right when finished...thats why i've always just flushed with new 50/50 as when a little gets left in there at least i have no worries about freezing from too much water. This should get the heater core working properly right away, though. Once done, put the rad cap back on, and top off the reservoir to full. Monitor the reservoir for the next couple of days, air will be bled into that and its level will go down over the next 100 miles or so.

I understand the car isn't necessary yours right now...but thats basically how it is done.

 

[Installshield 2]

Also, luckily a bad head gasket will create more problems than just no heat. I'm guessing the head gasket is fine if this really is the only thing happening. When you change the coolant, look at whatever you collect it in. Sludgy oil will rise right to the top, creating a gross film that should be noticeable right away. Check and change the oil too if you can, looking for a coffee w/ cream like appearance to it. does the engine miss at all?...bad HG's can get coolant/water into the combustion chambers...water doesn't ignite, but even worse...does not compress...which will make an engine be very noticeably off power wise...you can also rent compression guages from most parts stores...auto-zone has them for free. A bad head gasket will often bleed cylinder pressure off...

The previous owner has had a lot of things changed with the cooling system...all of which will introduce A LOT of air to the system...and most shops are very half assed about bleeding a car's cooling system effectively because it will work itself out over time (assuming the owner is informed to constantly check the overflow reservoir)...but getting a big old pocket of air in the heater core will give no heat, and usually means coolant isn't circulating properly...which is why the engine will overheat.

 

[kosteniuks17]

Hey man my p5 overheated once on me while going down the highway, all of a sudden I saw steam coming from the hood. When I pulled over and opened the hood, the antifreeze was literally boiling out of the resorvoir and was evaporating out, completely bubbling out and spilling everywhere. Anyways waited for it to cool down and rode it back home on a cool engine. Switched out the thermostat and it was set to go. Hasnt overheated for another 50,000 now. Anyways I would put my bet that its the thermostat, plus its only like 20-30 bucks. So its worth changing out. and btw flip out the gasket while your at it, its like a two dolllar paper gasket thing.

 

[Brian75x]

Thanks everyone for the help. It sounds like it is at least worth trying to burp it considering the HG alternative. I'll see what the owner thinks about giving it a shot.

Thanks again.

 

[P-Funk!]

Blown head gasket or cracked head will 'push' the coolant out the overflow bucket. The radiator will be low on coolant and not give out heat tot he heater and run hot.

The key is the bubbles in the overflow tank - if just a 'burp was needed - it would not bubble. Not to be confused with steam/overheat.

BUT! Price it right and a new head/gasket is cheap and easy on this car

 

[superchargedx]

Hey There,

Honestly, I will bet you 10 to 1 that it is either the Tstat or air in the system....

As for the whole head gasket thing that I often see on this forum..... Please do not take offence to this but NEVER, EVER in my 12 years as a Mazda Master Tech have I ever seen a head gasket blow on any 2.0l Protege!!! The ONLY exception to this is when the customer is so out to lunch that when there Tstat sticks, they overheat the engine so badly that the head warps!!

I am not trying to be a smart ass, but more someone to provide a little better info on such topics.. I think a few may be a little confused as to the order of failure in this respect!

Sean

 

[P-Funk!]

(popcorn)

 

[Jordysoso]

My motor had a legitimate blown head gasket. The motor was missing a dowel pin... Lol

 

[hat1018]

And the verdict is.......

 

[superchargedx]

Respectfully,

If your motor was missing a dowl pin............. there is alot more to that story!!!
If that was the problem from the factory, then it would have been an issue from near day 1!!!
If it was missing a dowl pin because the motor has been apart, well....... need I say more?

Sean

 

[Jordysoso]

No I know. Bought it from a POS used car place and discovered that when I tore down the motor. Caused a small leak on the exhaust side. I think someone (from Cleveland....) pulled the motor apart in their garage, got high, and forgot something. Lol but it's all good now.

Anywaysss, what did the problem turn out to be?