Help Chasing a Coolant Leak

Stereww

New member
I have been chasing coolant leaks ever since I bought my 4Runner. It had strawberry milkshake when I bought it. The previous owner wasn't aware of what that was and thought a new radiator would solve the problem, it didn't obviously, so I had to put a new tranny in it. The lines to the rear heater were causing coolant to leak pretty bad, I have since deleted those and solved that problem. Now I have this weird coolant leak that looks like it is coming from the AC compressor. I pressure tested the system, it slowly lost pressure and the drip emerged. I have attached a picture in the link below.

The first picture is taken from below, looking up through the engine bay on the passenger side at the front of the oil pan right below the AC Compressor. The bottom of the picture is towards the front of the vehicle. The red circle is the highest point I can see the leak. I'm not even really sure what that is, looks kind of like a bolt, but it's really tight in there right between the AC compressor and the oil pan. The coolant then drips down onto the wire loom and spreads from there. The purple is the path of the leak. When it is really leaking it also begins to drip from the bottom of the compressor at the third unconnected purple circle.

The second photo is just behind the radiator on the passenger side looking towards the rear of the vehicle. You can see the drip in the background (red circle). I took this picture because I thought the lines running through here may be causing the leak and I couldn't get my head in there. Doesn't look like it to me though.

Coolant Leak Pictures - Album on Imgur

I'm not sure if the previous owner messed something up putting in the new radiator, or if I did, putting in a new transmission or deleting the rear heater lines. I cannot see coolant anywhere in the engine bay from the top. I feel like I have tried every angle and there is always nothing. I don't have any experience with the cooling system in these 4Runners and I thought someone who has done this kind of work before would have a better idea.

Also, I took the timing belt cover off and got some pictures of the timing belt, just looking for some more opinions on whether or not you guys think it needs to be changed!

Timing Belt Pictures - Album on Imgur

Any help or advice is appreciated. I would like to get my leaks sorted before I put on skid plates and TB done if it needs to be. Thanks!
 
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The timing belt looks fine. It's hard to tell where your leak may be coming from with all the other residue. You might try pulling back the lower timing cover to look at the water pump.
 
The timing belt looks fine. It's hard to tell where your leak may be coming from with all the other residue. You might try pulling back the lower timing cover to look at the water pump.

Thanks for your quick reply, I really hope it's not that. Do you know if I would have to remove all of the drive belts to get to that lower timing cover? In this video of a Timing Belt job from Timmy it looks like the water pump was leaking pretty bad, but doesn't look like it was leaking over on top of the compressor?
Toyota Timing Belt Replacement (PART 1) for 3.4L V6 5VZ-FE (4runner, Tacoma, Tundra & T100) - YouTube
 
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I have been chasing coolant leaks ever since I bought my 4Runner. It had strawberry milkshake when I bought it. The previous owner wasn't aware of what that was and thought a new radiator would solve the problem, it didn't obviously, so I had to put a new tranny in it. The lines to the rear heater were causing coolant to leak pretty bad, I have since deleted those and solved that problem. Now I have this weird coolant leak that looks like it is coming from the AC compressor. I pressure tested the system, it slowly lost pressure and the drip emerged. I have attached a picture in the link below.

The first picture is taken from below, looking up through the engine bay on the passenger side at the front of the oil pan right below the AC Compressor. The bottom of the picture is towards the front of the vehicle. The red circle is the highest point I can see the leak. I'm not even really sure what that is, looks kind of like a bolt, but it's really tight in there right between the AC compressor and the oil pan. The coolant then drips down onto the wire loom and spreads from there. The purple is the path of the leak. When it is really leaking it also begins to drip from the bottom of the compressor at the third unconnected purple circle.

The second photo is just behind the radiator on the passenger side looking towards the rear of the vehicle. You can see the drip in the background (red circle). I took this picture because I thought the lines running through here may be causing the leak and I couldn't get my head in there. Doesn't look like it to me though.

Coolant Leak Pictures - Album on Imgur

I'm not sure if the previous owner messed something up putting in the new radiator, or if I did, putting in a new transmission or deleting the rear heater lines. I cannot see coolant anywhere in the engine bay from the top. I feel like I have tried every angle and there is always nothing. I don't have any experience with the cooling system in these 4Runners and I thought someone who has done this kind of work before would have a better idea.

Also, I took the timing belt cover off and got some pictures of the timing belt, just looking for some more opinions on whether or not you guys think it needs to be changed!

Timing Belt Pictures - Album on Imgur

Any help or advice is appreciated. I would like to get my leaks sorted before I put on skid plates and TB done if it needs to be. Thanks!

There is a coolant bipass pipe under the intake in between the heads in the valley. It is rtv'ed in the front and runs to a foam gasket in the back which collectsthe coolant and drips. A telescoping mirror would come handy.
There is a pic of the tube in the following thread.
Help - coolant in the valley - why?

Here is a diagram of the coolant pipes per the fsm.
 

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There is a coolant bipass pipe under the intake in between the heads in the valley. It is rtv'ed in the front and runs to a foam gasket in the back which collectsthe coolant and drips. A telescoping mirror would come handy.
There is a pic of the tube in the following thread.
Help - coolant in the valley - why?

Here is a diagram of the coolant pipes per the fsm.

Thanks for your reply and that diagram, I'll be sure to check it out.
 

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