Year and engine would help. The 3.5L and 3.9L engines had a coolant crossover pipe leaking problem.
Any chance this isn’t the head gasket? (2003 3.4L)
Back of engine, bottom, passenger side, below steering pump and alternator.
So I know it’s not the intake manifold gaskets, because I just did them and it had no effect. This leak looks exactly like it did before I did that job.
I caved in and bought a combustion gas test kit, and it did turn
What I wonder and hope someone might confirm is, is there any chance this could be the timing chain cover gasket? From what I can gather, it could cause the leak, just not sure if it definitely couldn’t cause the positive combustion gas test as well.
It had so many problems leading up to this that I’m not sure how to describe everything. It had been losing coolant and overheated at least once (which may be what blew the gasket if so), and there had been a lot of sludge in the cooling system. What I can say right now is, no white smoke, at least. Just this copious leak.
Another possibility I can imagine is, there’s an internal head gasket leak or cracked head in addition to this leak, which might still be the timing chain gasket. The more I learn about these cars, the more I would consider multiple problems at once.
Thanks in advance—trying to decide if this car is worth the work. Only 86k miles. From the outside or sitting in the cabin, it seems crazy to essentially scrap it, but here I am.
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Sorry about that … 2003 3.4L.Year and engine would help. The 3.5L and 3.9L engines had a coolant crossover pipe leaking problem.
The water pump and/or coolant bypass elbow aren't leaking?
Not saying head gaskets can't leak coolant externally but I'd look at the water pump and the coolant bypass elbow first.
Not saying head gaskets can't leak coolant externally but I'd look at the water pump and the coolant bypass elbow first.
I really appreciate the response. This is the rear of the engine compartment and I can’t see any way the water pump would be putting coolant there … water pump itself shows no leakage. But I’d love it if it could be that somehow.The water pump and/or coolant bypass elbow aren't leaking?
Not saying head gaskets can't leak coolant externally but I'd look at the water pump and the coolant bypass elbow first.
I’ve heard talk of these elbows but had thought they were limited to the 3.8s (this is a 3.4). I’ve been in there down to the LIM and never saw any hoses or such going through there. There’s a metal coolant bypass that runs across the front of the engine compartment over to the heater hoses, but it’s even further away from this spot and also completely dry.
Thanks again for the thoughts … I would really love for this to be something I’m just not getting.
What does your engine oil look like?
That’s the other part that doesn’t really seem to add up … I’ve never had the “milkshake.” The coolant seems to pick up some oil (not huge amounts) but I haven’t seen any coolant in the oil. It all makes me think there might be several issues going on here.What does your engine oil look like?
I've seen freeze plugs rust through as well.
You may want to look up there and make sure.
Head gaskets aren't a much more miserable job than lower intake gaskets. I usually do head gaskets on a GM V6 when I do the intake gaskets it's just a few more bolts and a lot more clean up. Once it's done it's done and I don't have to worry about whether it's going to blow them later or not.
The miserable part is getting the exhaust manifolds loose.
You may want to look up there and make sure.
Head gaskets aren't a much more miserable job than lower intake gaskets. I usually do head gaskets on a GM V6 when I do the intake gaskets it's just a few more bolts and a lot more clean up. Once it's done it's done and I don't have to worry about whether it's going to blow them later or not.
The miserable part is getting the exhaust manifolds loose.
Thanks ... I hadn’t heard of freeze plugs before — will check for sure.I've seen freeze plugs rust through as well.
You may want to look up there and make sure.
Head gaskets aren't a much more miserable job than lower intake gaskets. I usually do head gaskets on a GM V6 when I do the intake gaskets it's just a few more bolts and a lot more clean up. Once it's done it's done and I don't have to worry about whether it's going to blow them later or not.
The miserable part is getting the exhaust manifolds loose.
Definitely really wish I’d gone those few extra steps when I did the LIM. I was right there thinking I’d really regret it later if the head gasket blew or was already blown. Definitely a live and learn experience there.
Have heard about people having to cut the manifold bolts?
That's it.
Back of engine, bottom, passenger side, below steering pump and alternator.
So I know it’s not the intake manifold gaskets, because I just did them and it had no effect. This leak looks exactly like it did before I did that job.
I caved in and bought a combustion gas test kit, and it did turngreenyellow — exhaust gas is in the coolant. (And yes, I wish I had done that first, but I was still hoping.)
What I wonder and hope someone might confirm is, is there any chance this could be the timing chain cover gasket? From what I can gather, it could cause the leak, just not sure if it definitely couldn’t cause the positive combustion gas test as well.
It had so many problems leading up to this that I’m not sure how to describe everything. It had been losing coolant and overheated at least once (which may be what blew the gasket if so), and there had been a lot of sludge in the cooling system. What I can say right now is, no white smoke, at least. Just this copious leak.
Another possibility I can imagine is, there’s an internal head gasket leak or cracked head in addition to this leak, which might still be the timing chain gasket. The more I learn about these cars, the more I would consider multiple problems at once.
Thanks in advance—trying to decide if this car is worth the work. Only 86k miles. From the outside or sitting in the cabin, it seems crazy to essentially scrap it, but here I am.
I've cut the ends off nearly rusted away exhaust manifold bolts with a torch. Once the manifolds are off they usually back out with a stud extractor.
I would douche that off and look over the timing cover for leaks before condemning the head gaskets.
The timing cover is the back half of the water pump and it connects to two coolant passages in the block to the left and right of the cam sprocket similar to a smallblock V8 when you take a glance at it without the timing cover in place.
Just like a smallblock water pump you want to put RTV in the threads of the bolts that run into the cooling jacket when you re-assemble the timing cover.
This is a pic of the 3400 in an Equinox without the timing cover in place. This guys' engine was peeing coolant just exactly like yours is.
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This is the coolant leak on the Equinox in question. It looks really familiar.
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I would douche that off and look over the timing cover for leaks before condemning the head gaskets.
The timing cover is the back half of the water pump and it connects to two coolant passages in the block to the left and right of the cam sprocket similar to a smallblock V8 when you take a glance at it without the timing cover in place.
Just like a smallblock water pump you want to put RTV in the threads of the bolts that run into the cooling jacket when you re-assemble the timing cover.
This is a pic of the 3400 in an Equinox without the timing cover in place. This guys' engine was peeing coolant just exactly like yours is.
This is the coolant leak on the Equinox in question. It looks really familiar.
Thanks so much--that really helps confirm a suspicion here. It really does seem like that’s the source of what I can see here. I do have the positive combustion gas test as well, so it seems possible it’s that plus maybe an internal head gasket leak or crack as well.I would douche that off and look over the timing cover for leaks before condemning the head gaskets.
The timing cover is the back half of the water pump and it connects to two coolant passages in the block to the left and right of the cam sprocket similar to a smallblock V8 when you take a glance at it without the timing cover in place.
Just like a smallblock you want to put RTV in the threads of the bolts that run into the cooling jacket when you re-assemble the timing cover.
This is a pic of the 3400 in an Equinox without the timing cover in place. This guy was peeing coolant just exactly like you are.
View attachment 167290
This is the coolant leak on the Equinox in question. It looks really familiar.
View attachment 167291
When you did that, did you replace the oil pan gasket? I’ve seen conflicting reports on whether that’s necessary. It’s kind of a weird intersection of covers and gaskets right there.This is the coolant leak on the Equinox in question. It looks really familiar.
View attachment 167291
You can sometimes douche the gasket off with brakeclean, put a dab ov RTV in the corners, and put the cover back in place. Don't splooge a ton of RTV in the corners, a little goes a long way.
Worst case the pan gasket leaks oil so you have to pull the oil pan and replace the gasket.
Worst case the pan gasket leaks oil so you have to pull the oil pan and replace the gasket.
Great advice — thanks again. Definitely a more unusual kind of problem that doesn’t seem to be covered in a lot of places. May not be my only problem here, but definitely seems like at least one of them.You can sometimes douche the gasket off with brakeclean, put a dab ov RTV in the corners, and put the cover back in place. Don't splooge a ton of RTV in the corners, a little goes a long way.
Worst case the pan gasket leaks oil so you have to pull the oil pan and replace the gasket.
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