Water pump or head gasket

choff1212

New member
Good evening everyone, I have a riddle that needs a little help solving. First a little background on the truck. (I'll try to keep this short) Pick up a 2001 SR5 3.4l auto with 164,000 about 4 months ago. Clean 1-owner history timing belt and water pump changed at around 100,000 via service record, only problem was a possible charcoal canister failure. New canister and 1,200 miles without a CEL. The truck now has 169,000

Saturday night I drove the truck about 10 miles on the highway, when I pulled into the driveway I heard a hissing and saw some steam from the overflow. Once cooled I opened the radiator and found it dry with a bum radiator cap and the overflow reservoir had a quart and a half of oil in it. No power loss, rough idle, cold start white smoke from the tail pipe, pink milkshake, cloudy oil on the dipstick, chocolate mouse under the oil fill cap, visible leaks from the head/spark plugs, or overheating via the idiot gauge. Nothing looks out of place except the radiator and reservoir.

All of these symptoms lead me to believe it is one or all of the following options: Water pump crapped out, thermostat is shot, or oil cooler o-rings gave. The plan right now is to replace the radiator cap, thermostat, oil cooler o-rings, radiator, cooling system flush, engine flush, and any other maintenance that was probably forgotten by the PO.
 
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You sure it was oil in the overflow? Usually the coolant leaks into the oil, not visa versa since the coolant is thinner and is under pressure.
 
When my head went, I had white smoke whenever the truck was going slowly. Temp guage was up and down like a bride's nightie. But either way, what you are already replacing is wise and fingers crossed will cure it.
 
Why are you throwing parts at it without troubleshooting first? At least do a pressure check of your cooling system and do some compression tests.

Always do the easy stuff first.

Go from there.
 
The parts listed above are due to be replaced in the next 30,000k Miles anyway, figured if one or all could be failing I could get a jump on replacing them. There's about a quart of oil or some other extra fluid in the overflow tank. Oil dipstick is showing the correct oil level so I doubt that is the problem and the color is not alluding to transmission cooler failure. Maybe the previous owner put some weird leakstop in the radiator. Either way the oil and transmission fluid are getting dropped this weekend. Pictures will follow.
 
Here's a weekend update: Dropped the oil and took a sample of the transmission fluid and coolant. Also found that the overflow reservoir pipe that connects to the cap had fallen off; radiator cap is shot as well. Pretty much ruled out pink milkshake and blown head. Next step is tracking down the culprit in the cooling system. Let me know what you guys think. Pics taken during the process:

Trans fliud dipstick:
<a data-flickr-embed="true" href="https://www.flickr.com/photos/148776055@N07/30764334766/in/album-72157672371722163/" title="4runner misc"><img src="https://c7.staticflickr.com/6/5592/30764334766_0d0c1d20ce_n.jpg" width="240" height="320" alt="4runner misc"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

Oil dipstick:
<a data-flickr-embed="true" href="https://www.flickr.com/photos/148776055@N07/30764335396/in/album-72157672371722163/" title="4runner misc"><img src="https://c5.staticflickr.com/6/5758/30764335396_7b3afd0e90_n.jpg" width="240" height="320" alt="4runner misc"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

Reservoir tank:
<a data-flickr-embed="true" href="https://www.flickr.com/photos/148776055@N07/30764335746/in/album-72157672371722163/" title="4runner misc"><img src="https://c3.staticflickr.com/6/5575/30764335746_eef6abd81c_n.jpg" width="240" height="320" alt="4runner misc"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

Rad cap:
<a data-flickr-embed="true" href="https://www.flickr.com/photos/148776055@N07/30764336436/in/album-72157672371722163/" title="4runner misc"><img src="https://c5.staticflickr.com/6/5565/30764336436_7526153fc3_n.jpg" width="240" height="320" alt="4runner misc"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

Oil sample for Blackstone:
<a data-flickr-embed="true" href="https://www.flickr.com/photos/148776055@N07/30764336926/in/album-72157672371722163/" title="4runner misc"><img src="https://c7.staticflickr.com/6/5815/30764336926_e63899e9d4_n.jpg" width="240" height="320" alt="4runner misc"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

Reservoir tank contents:
<a data-flickr-embed="true" href="https://www.flickr.com/photos/148776055@N07/30764338226/in/album-72157672371722163/" title="4runner misc"><img src="https://c3.staticflickr.com/6/5724/30764338226_25fc73a22d_n.jpg" width="240" height="320" alt="4runner misc"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

Trans fluid (needs a flush asap):
<a data-flickr-embed="true" href="https://www.flickr.com/photos/148776055@N07/30764340786/in/album-72157672371722163/" title="4runner misc"><img src="https://c3.staticflickr.com/6/5471/30764340786_5085797b43_n.jpg" width="240" height="320" alt="4runner misc"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>

Radiator drain:
<a data-flickr-embed="true" href="https://www.flickr.com/photos/148776055@N07/30764342156/in/album-72157672371722163/" title="4runner misc"><img src="https://c5.staticflickr.com/6/5543/30764342156_7b7f2e3af7_n.jpg" width="240" height="320" alt="4runner misc"></a><script async src="//embedr.flickr.com/assets/client-code.js" charset="utf-8"></script>
 
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Looks rusty in the overflow. Tranny fluid is due for a change like you said. The coolant from the radiator looks fine. The culprit is likely your radiator cap.
 
Yeah that's not oil, that's burnt coolant. Turns from green to rusty orange when you've overheated the system. Ask me how I know.

Get that all out and maybe, just maybe you didn't damage the head gaskets.
 
All of you, thank you for the advice. I just finished up flushing the coolant and replacing the radiator cap; test drive went smoothly. My next move is to get a systems monitor to see where all my temps are at. Hopefully the oil test comes back clean. Once again thanks for all the help. I'll keep you posted.
 
That tranny fluid looks terrible. I wouldn't bother with a simple drain/fill, I would do a complete fluid exchange.

Mtbtim has a video showing you how to flush out all of the old fluid and replace it with new fluid.

Blackstone results will tell you a lot more. If the oil comes back fine, you should be good to go once the issue is found and resolved.
 

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