Leaking Coolant

Hey Guys, I have a coolant leak behind the thermostat housing in my 2002 V8 Tundra. Photo attached as to where the leaking is coming from and was wondering if anybody has fied a similar leak so I will know what I'm up against.

Thank you!

 

Is that the V6? Maybe I'm crazy but it doesn't look like the 4.7L

 

Had same thought but I ass u me it's simply a picture used from Haynes repair manual ?

 

Yep, my Tundra has the 4.7L and the picture is from a Haynes manual. Since I have not started taking mine apart yet you can't see that part very well and has red coolant all over it.....

 

Look at the thermostat parts diagram on page 2054 of factory service manual in the link below. Maybe just need to replace that gasket.

https://drive.google.com/file/d/0B-5MhfqaHsHObmt6RDVhOGtKWjA/view

 

I just found one on my truck the other week too, I found a video on YouTube of someone doing the fix, looked fairly straight forward just haven’t had the time to tackle it yet.

 

Thank you guys, #weadjust- the leak is coming from behind the thermostat housing. #Filthyphil-that's where my leak is coming from, I will swing by the dealer tomorrow and see about picking up that gasket. I will post the results this weekend!

 

Did you ever get around to doing this?

 

Yes I did, it was straight forward, there is a u-tube video that is pretty helpful. The coolant leak was from the round port in the manifold(behind where the thermostat is housed) the gasket was so brittle that it just crumbled when I pulled it out, it was only a few bucks at the dealer. The rectangular port is sealed with silicone but you need to remove the old silicone first. I started with a blade from a box cutter but did not have good results, I then tried it with a 99 cent wire brush the size of a toothbrush from Harbor Freight and that worked very well as you can see in the picture. I did not read the instructions on the RTV high temp silicone and it says to apply the silicone on the faceplate but wait an hour before you torque it down. I torqued it down right away but it is not leaking and I doubt it will. After this, I fired up my Tundra and noticed I had a radiator leak about 1/8" stream- too big to try and use a sealer so I replaced the radiator as well as all the hoses- including the ones that go to the transmission and the cooler. Since I had it all apart might as well take care of it, I also replaced the thermostat and the weep hole that is supposed to be lined up at 12 o'clock instead was at 6. Not sure if it came from Toyota that way or someone had already replaced it before but it is now installed correctly....

 

Very nice, did you have to remove the belt to get that hose off? Or did you just leave it connected?

 

I did not have to remove the belt when I changed the gasket/silicone on the manifold or when I replaced the radiator. Plenty of room to work with the belt still on, pretty easy job, just need patience as I ended up with a squirt of transmission fluid on my head when I disconnected one of the small lower hoses that go to the radiator....

 

From the look of the Orange silicone it has been off before, factory only uses black rtv, never orange.

I have found the best way to dig out the old silicone from the rectangle groove was to use the back side corner of a single sided razor blade with brake cleaner.

 

thx Neutron

 

LoveLabs do you remember what you searched in youtube to find the video you watched?

 

@BuddhaBread, I could not find the exact video, but there are several that describe replacing the thermostat on a Tundra and if you have a leak on the manifold behind the thermostat you just keep going take that part off and replace the round gasket. Remember that the rectangular manifold uses RTV silicone instead of a gasket. As a matter of preventive maintenance if you have to replace the thermostat or take apart that housing I would also replace that back gasket, on a gen1 tundra those gaskets should be pretty brittle by now and the gasket cost a couple bucks. If you have specific questions let me know but the job is pretty straight forward. Good luck!