Rusted Y-pipe...does this look bad?

[uhhair]

So we have our new D disassembled down to the block so that we can redo the whole fuel and cooling systems then try and get the car turned over. However, when we removed the Y-pipe we found it like so (see attached pictures.) I also included pics of the two intakes on the block that the y-pipe connects to. My question is, how bad is this? Is this normal for a car that has been sitting for 20 years? Does this indicate any possible block rot? Also, I'm assuming we should at least invest in a new pipe, yes?

[Mark D]

Yikes... I'm not an expert when it comes to the valley of death and that coolant pipe, but it certainly doesn't look good when there is so much buildup that it's completely blocked. I'm interested to hear what the pros have to say on this as well.

[dmc6960]

Yes, it looks bad.

No, you dont HAVE to get a new one. This one could be carefully cleaned up internally and externally. Watch for pits in the aluminum, if there are any deep ones, its toast. But besides the buildup internally I dont see any large-scale aluminum corrosion. This pipe isn't steel, so it doesn't technically rust, but can still corrode.

I'd also recommend removing both drain plugs in the engine block and run water through them for a long time on each side (stick the hose into each y-pipe port). Probably want to do the heads too. If there is too much buildup internally on the engine components, that will insulate the engine from the coolant allowing for it to overheat.

[Bitsyncmaster]

If you're doing a complete block tear down, you can decide from what you find. I would not use that engine without knowing what it looks like inside.

[uhhair]

We did pull both drain plugs and run water through the ports, about 5 minutes per side. Should we do it for longer? Also, do you think a head job is necessary just to assemble the engine and try and run it as an initial test to see if it even works? Our issue is we don't want to stick lots of money into an engine that has a bad block or block rot. My solution was to simply clean out all this stuff, reassemble with a new cooling and fuel system and start it up and see what happens. If the engine holds pressure and appears to work fine then move on over the winter to things like heads, ect. Thoughts?

[Morpheus]

From the looks of pic#2 you posted above, I wouldn't do anything else until you take off those heads and see what you're dealing with. There is a lot of rust down there, with any luck it's you'll just be replacing your liners.

[WelmoedJ]

From the looks of pic#2 you posted above, I wouldn't do anything else until you take off those heads and see what you're dealing with. There is a lot of rust down there, with any luck it's you'll just be replacing your liners.

If you're successful in clening out the Y pipe, check the surfaces of each of the connecting openings to the block.
If they are too much pitted in the O-ring area they probably won't seal well.

Also check the openings of the ThermalAVC switch, the Lambda-switch and the idle temp switch.
If they're not sealing well, you'll have to get in again to clean out the VoD.
Make sure all connecting surfaces seal perfectly.
You can check once finished assembling the cooling system using water and a pressure tester.

[DMCMW Dave]

When you are looking into the holes where the Y-pipe was you are seeing the side of one of the cast iron cylinders. So - you have a direct shot into the cooling jackets. Between that and what you see in the Y-pipe I'd be very afraid.

[uhhair]

Dave, afraid of what is my question?

[David T]

It is unusual to see the Y pipe blocked like that. I would wonder if any other cooling passages are similarly blocked. Especially the heads. The whole engine should be dismantled, rodded out, and then tanked. In fact, the whole cooling system should be taken apart and mechanically cleaned and flushed out. It probably doesn't make sense to even try to use the radiator if it has the plastic tanks. As for the block itself, clean out the recesses under the intake manifold and see if they are rotten. The block can probably be salvaged if the recesses are not rotted through. Just flushing through the side drain plugs does not mean all of the cooling passages are clear. With that much junk inside you may have enough corrosion that the bottom liner seals have been compromised and will leak once the motor heats up.
I would also expect pinholes in the aluminum pipes underneath the car. The car sat too long and the anti-freeze got corrosive.
David Teitelbaum

[uhhair]

It is unusual to see the Y pipe blocked like that. I would wonder if any other cooling passages are similarly blocked. Especially the heads. The whole engine should be dismantled, rodded out, and then tanked. In fact, the whole cooling system should be taken apart and mechanically cleaned and flushed out. It probably doesn't make sense to even try to use the radiator if it has the plastic tanks. As for the block itself, clean out the recesses under the intake manifold and see if they are rotten. The block can probably be salvaged if the recesses are not rotted through. Just flushing through the side drain plugs does not mean all of the cooling passages are clear. With that much junk inside you may have enough corrosion that the bottom liner seals have been compromised and will leak once the motor heats up.
I would also expect pinholes in the aluminum pipes underneath the car. The car sat too long and the anti-freeze got corrosive.
David Teitelbaum

Well, we already have a new radiator, we didn't intend on using the old one anyways with the car sitting so long.

We'll look at the recesses this week, We gave them a quick and dirty cleaning, and aside from having tons of gunk on the top of the engine, the top of the motor didn't appear to be rotted or anything like that.

It's interesting, because only one side was gunked up like that, the other side was much cleaner.

[Grover]

I am betting someone thought putting GM Dexcool in for coolant was an excellent idea.

13298

[82DMC12]

I am betting someone thought putting GM Dexcool in for coolant was an excellent idea.

13298

That's actually the first thing I thought. Death-cool....

Andy

[Grover]

That's actually the first thing I thought. Death-cool....

Andy

Also, I bet the previous owner used tap water instead of distilled water if they required to add any water to the coolant.

13299

Google tap water with coolant, then look at the images. Combine that with Dexcool and bingo. I'd check some of the crud with a magnet to make sure it's not metal/rust, but from what I see I am going to guess lots of Dexcool and normal tap water, plus 20 years of going unchanged.

[uhhair]

The only rebuttal I have to the Dexcool argument is that 1. The car wasn't driven after 1988, and Dexcool seems to be a mid-1990's issue and 2. The coolant in the car was green, not red.

[DMCMW Dave]

Dave, afraid of what is my question?

As other David (T) said - I'd be worried that the whole inside of the engine (and the cooling pipes AND the radiator) looks like that, and you can't rinse it out good enough. How long did this car sit before you got it? I'd guess 20 years. . . .

[DMCMW Dave]

Well, we already have a new radiator, we didn't intend on using the old one anyways with the car sitting so long.

We'll look at the recesses this week, We gave them a quick and dirty cleaning, and aside from having tons of gunk on the top of the engine, the top of the motor didn't appear to be rotted or anything like that.

It's interesting, because only one side was gunked up like that, the other side was much cleaner.

Not good - I'll be you have compromised cylinder seals or head gasket. What did the oil look like when you drained the engine?

[uhhair]

Not good - I'll be you have compromised cylinder seals or head gasket. What did the oil look like when you drained the engine?

The drained oil looked fine, it was dark but nothing out of the ordinary.

Okay so our follow-up question is this, and maybe this should be a new thread, but how does one check for block-rot. What do we need to do, what are we looking for, etc?

[Bitsyncmaster]

The drained oil looked fine, it was dark but nothing out of the ordinary.

Okay so our follow-up question is this, and maybe this should be a new thread, but how does one check for block-rot. What do we need to do, what are we looking for, etc?

You clean out the four deep recesses that you now can access with the Y pipe off. When you get it clean, look for bad pitting in those "holes".

[uhhair]

You clean out the four deep recesses that you now can access with the Y pipe off. When you get it clean, look for bad pitting in those "holes".

Okay sounds good, we'll clean those tomorrow and post pics/updates

[Morpheus]

You clean out the four deep recesses that you now can access with the Y pipe off. When you get it clean, look for bad pitting in those "holes".

That takes care of the outside, but I'm more concerned with the corrosion/rot on the INSIDE of this motor.

Uhhair, are you trying to avoid taking off the heads?

[uhhair]

Yes, we were trying to avoid taking the heads off but at this point it looks like we might not have a choice. A few other people have said we might be able to just flush the engine good so I'm really on the fence about this one. Was really hoping to not have to do a complete engine rebuild as that's a little out of my comfort zone so I'm not sure what to do here. If the engine is already bad, what is the harm in reassembling and starting anyways is my question?

[Bitsyncmaster]

Yes, we were trying to avoid taking the heads off but at this point it looks like we might not have a choice. A few other people have said we might be able to just flush the engine good so I'm really on the fence about this one. Was really hoping to not have to do a complete engine rebuild as that's a little out of my comfort zone so I'm not sure what to do here. If the engine is already bad, what is the harm in reassembling and starting anyways is my question?

I would wonder if your pipes and hose under the car is in the same shape. Do you really want to plug up a new radiator? Maybe you can run the engine with the old one, do a flush and see what comes out.

[uhhair]

Well, our problem is now we don't really want to reassemble the entire engine to start it up and then blow the thing up because we didn't go the extra step to remove the heads and find out exactly what is going on. Seems to be the smart play to just disassemble the whole thing now and get it over with, yes?

[deloumis]

Well, our problem is now we don't really want to reassemble the entire engine to start it up and then blow the thing up because we didn't go the extra step to remove the heads and find out exactly what is going on. Seems to be the smart play to just disassemble the whole thing now and get it over with, yes?

Yes. If the rest of your block looks this way you can possibly overheat your engine and ruin good parts. A lot of things can happen in which case you will end up buying parts you didn't initially need which you could have avoided if you took a look.

[DeLorean]

Use of well water or other high mineral content water can do this to a cooling system faster then you might think. I would highly suspect that early on in this cars life it suffered from a loss of engine coolant, which was topped off every once in a while with the same water source- which was likely very high in mineral content... It can be almost as corrosive as salt water. With how bad that Y-pipe is, I'd pull the whole motor and every single piece of that cooling system to do a complete inspection on every single piece. If the Y pipe looked like this, Freeze plugs, radiator, heater core, aluminum coolant hoses... everything is suspect.

[AirmanPika]

This is why I always use premixed stuff if possible. Less hassle and you know it should be safe as long as you use the right kind. I'm glad my car has been gently used (and abused) over the last 30 years because when I tore my valley apart the insides of the pipes and so on were nice and clean. Honestly some of those pipes in the pics look like they are clogged by purely hardened coolant besides all that rust. God knows what's in the block.

[LEVY]

Use of well water or other high mineral content water can do this to a cooling system faster then you might think. I would highly suspect that early on in this cars life it suffered from a loss of engine coolant, which was topped off every once in a while with the same water source- which was likely very high in mineral content... It can be almost as corrosive as salt water. With how bad that Y-pipe is, I'd pull the whole motor and every single piece of that cooling system to do a complete inspection on every single piece. If the Y pipe looked like this, Freeze plugs, radiator, heater core, aluminum coolant hoses... everything is suspect.

Actually, distilled water is a lot more corrosive than water with some mineral content.

Distilled water is "out of balance" and is looking for minerals to neutralize itself, inside your cooling system water can get minerals from your antifreeze or from the inside of the piping, radiator, engine block etc.

LEVY