Cooling System Ruined?

35th Anniversary Edition I bought non-running two years ago. West Texas for its whole life, it has 135k on it and, as I understand, was parked in 1998? due to a no crank no start. After solving those problems getting the engine to start and idle, I decided to address the cooling system since the water pump was seized. This is what I found:


So how bad is this? I have never encountered it this bad. I scrapped some of it away, but it appears to go all the way through the timing cover.

Is this because of head gasket in a can or is this just a product of it sitting for too long?
Will the engine and supercharger need to be completely disassembled in order to clean it out or can I use flush?
Or is this the end of the road for this motor?

Hey,

I have only ever done one head gasket change, and I had help, so I’m no expert. But that does look pretty serious. We’ll see what some of the more experienced SC experts say, but I wouldn’t give up on that motor just yet. Even if it turns out that repairing it would be too costly and/or labor intensive; I assure you that there are still some parts worth saving before you let it go.

Sadly, head gaskets are a weak point on these cars and they require a bit more maintenance than most to keep in good running shape. That said, there’s still a good amount of support for these cars. Hopefully you can fix it up and enjoy all the quirks and features that these cars have to offer.

-Rick Leuce

Interesting you got it running.

What does the oil look like on the dipstick? Did you do an oil change? What does the underside of the oil filler cap look like? What came out of the exhaust when you had it running? Smell? Steam? smoke....?

If you haven't done an oil change, I would at least drain that oil and see if it looks milky, gummy, etc., or just old and dirty.

When the head gaskets go, you can see exhaust gases in the coolant and not coolant in the oil if the fail isn't extreme, or lots of coolant in the oil if a bad fail. I don't think what we see in the photos is a mix of oil and coolant.

My opinion is that after so many years, chemical changes/breakdown from old coolant and interaction with aluminum took their toll, leading to the crystallization in the photos.

I imagine the block could be torn down and boiled out, etc. but the real risk may be to the aluminum components of the cooling system, from the radiator, to the heater core, to the heads and the timing cover.

I don't see a simple save like flushing being capable of having an impact on the hard crystallized residue.

You could take the top end down and pull the heads to confirm if the same residue is present in that part of the block, and have a shop examine the heads, maybe there is a chance the block isn't as bad as the water pump/timing cover, then decide plan from there.

That isn’t a head gasket issue, that is just from coolant sitting for 20 years. I would start by chipping away what you can see there, fill the block as much as you can with some CLR, and then flush the whole thing out with a garden hose. Follow this up with a new water pump and thermostat, and see where you are at. If that doesn’t work, the next step will be to pull the motor out of the car, knock out all the freeze plugs, and get in there with wire brushes and things like that to clean all that crud out of there.

Good morning

I agree with KMT for a top engine tear down. I have worked on 35th last run 14 years ago. In my case the heads gasket between the coolant passages and the fire rings were damaged. Heads surfaces had slight corrosion pitting. If there is any additional maintenance items to be address with the heads off/additional access now is the time.

I did the following:

Machine shop recondition heads.

Checked engine oil. Was not contaminated.

The radiator had to serviced (boiled and rodded out). Water pump, thermostat, engine coolant sensor, almost all of the coolant hoses replaced.


Harmonic balancer (rubber cracked) and oxygen sensors (heavy dark brown coating) replaced.

New spark plugs and wires.

Cleaned EGR passage to plemen.

Re-assembled. Changed oil and filter. Changed fuel filter.

Use a professional heavy duty coolant cleaner from @NAPA to flush system. Ran engine. Replaced anti-freeze/coolant.

No other defects found. Return engine to service.

Thank you for all the replies. It really helps the hear that this engine is most likely salvageable.

It was hard to get running, rat damage to the wiring harness combined with a rogue anti-theft system, bad IRCM and fuel pump. But I did get it to start and idle with the IAC unplugged.

I did an oil and filter on it before attempting to crank it. The old oil did not have any separated water or coolant in it, just very thick, black and stinky.

I have a new water pump, molded upper and lowers hoses, heater core hoses, thermostat and housing, and radiator. I will get the temp sensor as well. The hose coming off the bottom of the water pump to the oil cooler appears to have liquid coolant in it and is not gummed up, but I will disconnect it and verify.

I will try to use my heater core blast gun and hot water on it and then put my inspection camera in it to see how far I get. I will also inspect the heater core itself.

Once again, thank you! I will report back.

The heater core isn't fun to change out - dash has to be pulled, so don't get carried away if you try to blast it. Would be a shame to blow up an otherwise good unit. Good news is they don't cost much and as far as I know, are still available in the aftermarket.

What you describe about the oil is encouraging.

Inspection cam for the win