RESOLVED: coolant leak after timing belt replacement

Well, I hate to say it, but where is the weep hole?

I saw another thread where someone had multiple but somewht similar problems. One of the issues they said was that the weep hole was at the 6 o'clock position instead of the 12 o'clock position. Unfortunately, I still am unaware of the weep hole location even after looking at their pictures.

 

I’ve got a new one in a box waiting for install but it’s at the shop so I can’t locate and take a picture for you rn. When I last did my timing belt I had a coolant leak also, but it was from reusing the factory radiator hose clamps. Major leak at the upper to WP / thermostat connection. Had to back the factory clamp off and add a worm drive.

 

A new what exactly?

I still have all of my old parts so I might locate it on those

 

Did you use the petcock on the engine block to drain the coolant initially? There's a little valve that a lot of people use to drain the coolant from the engine block.

 

That weep hole is the "jiggler" valve (their description, not mine lol) on the thermostat. That wouldn't cause an external leak.

 

Yes, I drained from both sides of the engine block after draining the radiator. And I double checked those to be sure they are all snugged up and there is no coolant coming from either side

 

I have a new water pump. The weep hole I’m referring to is typically located on the water pump itself. I don’t have the pump with me to see where it’s located.

 

This is where the weep hole is located. The weep hole might seep a little bit of fluid during the first 10 minutes or so after you install the water pump or run the engine, but that will stop and it shouldn't be gushing out from here.

 

The leak picture sure doesn't look like a gasket, FIPG or weep hole leak. That is a big leak. A hose disconnected kind of leak.

Is the rear oil cooler hose hooked up? It's behind the AC compressor and a pain in the @$$ to get to.

This is why I suspect the rear cooler hose:

 

I agree that it is not a gasket FIPG or weep hole leak. Coolant comes out At a high rate


I can only do a little bit a day because of how weak I am from Covid but at least I got my truck moved back under my work area. So that cooler hose will be the first issue I explore.

Makes the most sense

 

if that hose you're speaking of connects by the oil filter closest to the truck cab (orange arrow)



and then runs by the dipstick and connects at the engine block (orange arrow below)

Then, yes, it is secure and it is also dry at the engine block


But what is obvious is that it is very wet with coolant behind the AC compressor (yellow arrow above) and I can see that's where the coolant is flowing. Not necessarily close to the source, but that is where it is flowing down to the ground


I've started taking off the ac compressor to see if I can follow the coolant flow. Probably going to have to also take off dr side timing belt cover at a minimum.

don't recall any other oil cooler hoses, etc that are higher in that area

 

That is the line I was thinking. Yours's is definitely dry.

Good luck on the search. The only other line I can think of in that area is the same one @Mr Badwrench mentioned on page 1.

 

Thanks. I checked the hose he mentioned. It check out ok and it is dry in that area.

probably going to require an almost complete disassembly of what was removed for the timing belt job to ID to the source. I don't believe I have to remove the radiator, fan shroud, etc. just the serpentine belt, AC, compressor, driver side timing belt cover, etc. Mostly right / driver side

 

With the amount of leakage you’re describing - I can only imagine the WP didn’t take a good seal for whatever reason and is puking right there.

 

I guess we'll find out. I just cannot imagine that it would flow that much from that area because I know I torqued down the bolts properly and I know once I finger tightened those bolts I rechecked the gasket and it appeared to be perfectly in place

but running out of explanations so I'm not going to dismiss any possibilities

 

EDIT: 3rd a/c compressor bolt found.
There were two things I was going to go back and do once I tested everything. Install the AC support bracket and get new fan shroud bolts because this new Denso radiator is different from what was previously installed and the shroud had to be temporarily zip tied. So I had put the 3rd bolt where the secondary AC support bracket bolt should go


orig:

Currently having a hard time finding the third 14 mm bolt that holds the compressor

The support bracket is off

Rear 14 mm nut has been removed

Front top 14 mm boat that requires a wrench instead of a socket has been removed.

I didn't have any problem finding this before putting it back on

None of the videos seem to match up. Looking at the Haynes manual, it doesn't differentiate with the three shorter bolts versus the longer one, but it should be the rear top bolt


This is basic and simple. Don't know why it is giving me fits.


Put a little more water through the inlet where the top radiator hose connects. Is starting to seem apparent there is coming out the right side of the water pump. Hard to imagine that being a missing bolt or gasket issue but there's really not much left on that side.

I would like to get the AC compressor off first since it's got to come off at some point, but it looks like a complete timing belt removal/disassembly is in the future

 

I've seen new OEM WP gaskets that were damaged. Could that be the case here?

 

It seemed OK on my visual inspection

 

I don't know if it's been asked, but where did you get your water pump? Are you sure it's 100% authentic Aisin?

 

If I remember correctly - there is a nut holding the compressor on the driver’s side - mine was rounded off and we had to swedge on a 7/16” socket to get it off. Fun times.

 

Rock Auto

 

Alrighty then, we can probably eliminate it as the culprit.

 

There's a bunch of hoses that run down to the oil filter...any one of them could be leaking.

 

And this thing...the "water bypass" offers many opportunities for leaking

 

I already went down this road earlier in the thread after some suggestions, and it proved to be fine

Not sure where this is located

 

And there it is:



One missing bolt - lower right on the water pump. I was 95% or better certain it was coming from this general area

One I could've sworn the video said was used later by another part that connects

 

Glad you got it fixed!! What did I win?

 

You definitely called it

common sense should have supported this since I had eliminated every other hose, and I knew I did the gaskets correctly

and I don't mind one bit that I spent an hour and a half, mostly waiting on they were clear on the interstate to go to the Toyota parts dept to pick up another water pump gasket just in case. $21 I didn't mind spending.








Now, if anyone can point me to a diagram that shows where the crank sensor wire/harness is supposed to be routed, they would also win a great prize

I'm going to go back and look at the videos, but I don't recall them ever giving me good specifics on this

I believe I did it partially right (ie wrong) but still ended up zip tying it to be 100% because it just looked like it came a little too close to the belt

 

Yes yes yes. Really the only way in this case. Actually, much more and it didn't require me cranking the engines since it flowed freely while adding coolant

I just used distilled water for testing. Will drain that at the block before adding the good pink stuff