Mysterious water leak?.?

[SleekRunner]

Have you tried running coolant instead of water? You are talking about the blow-off from the radiator right? Maybe using coolant instead of water may do the trick. Speaking of i actually need to tip off mine with some coolant... Best of luck.

 

[Kotrin]

I did the recommended mixture of coolant and water. I did not think of the thermostat..maybe a good idea to do that plus water pump and timing?

 

[TheDurk]

I was actually having the same problem. I would smell antifreeze from outside my truck when it was running. No visual leaks any where. I was starting to get worried that it was my head gasket as well and brought it in to get it diagnosed. It ended up being the thermostat housing and gasket. Cheap fix. I also had the water pump done with my timing belt about a year ago which was also leaking. Usally if the water pump is leaking the antifreeze drips on the fan belts and you will hear a squealing noise coming from the belts. A sure sign the water pump is taking a dump.

That is usually true. But not on our 3.4L V6. The water pump is not near the 'fan' belts. It is under a cover driven by the toothed timing belt which will NOT squeal--if it does, the engine would immediately come to a semi-permanent stop.

Squealing belts for us means loose or worn accessory belts or a stuck PS pump, alt, or A/C compressor. Our W/P will advertise failure by leaking (often in a stealth manner) or very subtle timing belt noise, but not a squeal. The best check is looking behind the timing cover for dried coolant with an extension mirror.

Sorry, but I thought I should explain this.

PS. Don't go back to the mechanic who installed your W/P a year ago (no way W/P and thermo should leak after a year) and check your crank-bolt torque--he probably screwed that up, too--and the consequences could be dire.

 

[Kotrin]

I was getting ready to do the. Belt and pump...when I was oveer looking at 4x4wires site with the replacing timing belt guide and noticed my waterpump is behind the shroud. So if it is the culprit..where is the water going still out the seep hole down by the lower pulleys?

I've done a head replace and timing on an 87...I really don't want to pay 800 for the dealer to do it. As long as I got all the proper tools and follow the fsm...I should be good right? Anything in particular I should look out for?

Thanks in advance!

 

[lekiboy]

you may want to check the lower part of your rad...the leak i used to have is coming from the area where the grills and the plastic are joined....it is a slow leak also.
you can only see this from under the rad while the engine is at your back and the 4runner is lifted or raised...

you won't see this by just looking on top of the rad and peeking on some obviouis leaks on the lower part. look from the bottom.

 

[Kotrin]

I will look into it. I still plan to do the pump and such cause it leaks a fair amount then won't at all sometims leads me to believe it is more and more the pump plus I do not know whe the belt was done last

Any type of dye one could use to better see leaks? Or just clean up what looks like antifreezze leaks and see if they reappear?

 

[lekiboy]

I will look into it. I still plan to do the pump and such cause it leaks a fair amount then won't at all sometims leads me to believe it is more and more the pump plus I do not know whe the belt was done last

Any type of dye one could use to better see leaks? Or just clean up what looks like antifreezze leaks and see if they reappear?

a leak eventhough slow will appear still to be wet...touch it and see if it is oil or water...it is ovious to notice. wipe the leak and wait for it to reappear to confirm the location...

am not aware of any dye to use.

 

[Blitzkrieg]

You say its got a new radiator.

Completely draining a cooling system and refilling it, it's not uncommon for air pockets to make the initial fill low once they fill up. A gallon is a little much, but who knows what was done.

Take the radiator cap off and run the motor to operating temperature to burp the cooling system (purge of air). Fill everything up at that point and then keep an eye on it.

As advised above - if its a head gasket you will generally have one plug that looks way different (cleaner) than the others and the smell of burning anti-freeze is unmistakable - it's a very sweet, almost sugary smell.

Also, remember - a head gasket does not mean the head needs work (as long as it hasn't been warped from overheating. It should be noted that while the 3.0 litre V-6's are infamous for head/head gasket issues, the 3.4 are NOT and actually have proven pretty bulletproof in that aspect.

And lastly, you say you added "water". Never, ever add just water and never, ever add tap water. Use distilled water with a 50/50 mix of antifreeze.

Tap water plays havoc on aluminum parts and should be used for watering your lawn or peeing in, not your motor.

 

[49Runner]

As advised above - if its a head gasket you will generally have one plug that looks way different (cleaner) than the others and the smell of burning anti-freeze is unmistakable

And lastly, you say you added "water". Never, ever add just water and never, ever add tap water. Use distilled water with a 50/50 mix of antifreeze.

Tap water plays havoc on aluminum parts and should be used for watering your lawn or peeing in, not your motor.

Just did my head gasket... Definitely check plugs. If you find a wet plug, pull all the plugs and have someone crank the engine... You'll see spray if you have a bad gasket.

Other thing that is a warning is if it runs rough for the first 10-20 second after start up

 

[Kotrin]

I can never seem to gettthe quick reply to work for me...oh well. So I did the water pump seals and belt this weekend. Have driven it about 200 miles and she's holding water. The pump looked pretty bad..had the water residue on it so it does appear I found the culprit! Thanks for all your help ill still check out the head and write down your wonderful suggestions for future problems and to help others

 

[t4r4life]

get a pump for the rad and pump to 15 psi and check for all leaks everywhere the only way to find out really

 

[Kotrin]

So a follow up aftger I've put another 500 miles on it. Unfortunately it still has a slow leak. I think I'm smelling that sweet smell you were all talking about. Did a oil change / compression/spark plug replacement. Compression is 155 to 170, sparks plus were normal no unusual wear or color. Oil was standard no graying or discoloration.

So I'm probably good to assume the problem is the head gasket to the exhaust manifold yes? Not aware of any other test I can preform to check . It does on start up have your normal smoke and then it goes away. I don't feel or seem to smell it but at start ups after its sat awhile(a few hours).

Thanks for all your help in advance, and it might go through a cup a fuel tank or less.

 

[Singtoe]

You can't check head gasket leaks using pressure especially only 16 lbs worth. If you don't believe me that it is not the head gasket (assuming there is no visual leaks), take your truck to a Radiator shop. They have an apparatus that were measure if there is any CO (Carbon Monoxide) in the coolant. With the engine running, a tool is used to draw fumes from the cooling system through a chemical that checks for the presence of carbon monoxide (CO) in the cooling system. Carbon monoxide will only be present if the head gasket has failed or the cylinder head itself is cracked. The chemical starts off blue in color, but turns green or yellow in the presence of carbon monoxide. This test is known as a “block check." If there is, your HG is definitely shot or you have a cracked head.

 

[Diagram14]

One of the places my head gasket was leaking when it went was the back side of the motor (firewall side). What kind of gasket did you use on your new WP? There is always a chance it fail already.

 

[Kotrin]

Ill try to get it in and have them do the test for carbon.

Not sure about the gasket had that done so ill have them check it..its under warranty.

I only mentioned the head due to what people have toldme due to some of the signs aka pipe smell etc. I would hope its just the water pump again.. be nice. Any way I can do that test or do I gotta find a radiator shop?

 

[Singtoe]

Ill try to get it in and have them do the test for carbon.

Not sure about the gasket had that done so ill have them check it..its under warranty.

I only mentioned the head due to what people have toldme due to some of the signs aka pipe smell etc. I would hope its just the water pump again.. be nice. Any way I can do that test or do I gotta find a radiator shop?

Here is a place where you can buy it.

It might be cheaper to go to call some radiator shops and see what the charge to do the test for you.

 

[Kotrin]

Thanks. Ill call but. Most likely buy it it so I have it available for future checks =)

Thanks again.

Called and its only 24.95. Ill wait to buy it lol

 

[Kotrin]

Block check came back good. No other leaks even pumping it up. I did notice a small leak out my radiator cap the other day so going to try to replace that...other wise i think it might be the head :'( I understand that the cap leak wouldn't show up due to the cap not being on when you do a pressure check and such.
Comes at bad timing was hoping to do suspension upgrade not head lol.

 

[Hotkarl0_0]

Did you ever get this sorted?
I have similar symptoms.

 

[Mikey0449]

That is usually true. But not on our 3.4L V6. The water pump is not near the 'fan' belts. It is under a cover driven by the toothed timing belt which will NOT squeal--if it does, the engine would immediately come to a semi-permanent stop.

Squealing belts for us means loose or worn accessory belts or a stuck PS pump, alt, or A/C compressor. Our W/P will advertise failure by leaking (often in a stealth manner) or very subtle timing belt noise, but not a squeal. The best check is looking behind the timing cover for dried coolant with an extension mirror.

Sorry, but I thought I should explain this.

PS. Don't go back to the mechanic who installed your W/P a year ago (no way W/P and thermo should leak after a year) and check your crank-bolt torque--he probably screwed that up, too--and the consequences could be dire.

So im kinda new here and id didnt really know how to go about asking since i cant really post and you seem like you know a thing or two. I have a 2002 toyota 4runner and a leak that is coming out of what looks like a sensor located below the thermostat but after searching the web i cant figure it out any clues or help or other threads that would address this?