I’ve just acquired a 1980 Daimler Sovereign Double 6 that hasn’t run in years. Maybe many years. Someone mentioned that if the previous owner(s) had used water in the radiator, the water passages in the block and heads could be corroded to the point that the engine would only be good as a coffee table like you see on Top Gear. I drained the radiator and the ‘coolant’ was a dirty brown colour and I have no idea whether it was just water or proper coolant that’d gone off. If it was plain old tap water and if it’d been there for years, could the engine actually be rendered useless?
Without a tear down not an easy thing to say yay or nay to, you would need to take the heads off to see what damage, if any, there is to the water ways.
Useless? You bet, especially if the coolant froze. Drain the engine oil and see if there is water mixed with the oil.
As a comparison i recently drained the coolant out of an S3 4.2 that had stood at least 20 yrs in a field, It came out lovely and blue!
Things probably aren’t good there. I don’t think the engine itself will have suffered significant damage unless it was overheated, but there are at least four concerns:
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The coolant passages may be plugged up with mineral deposits. At the very least, this car should have Tefba filters installed in the upper radiator hoses before the first startup to catch anything that might get blown out.
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Mineral deposits may have accumulated around the head studs which can make the heads VERY difficult to get off.
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The head studs are immersed in the coolant. If they’ve been immersed in plain water long enough, the corrosion on those studs may have effectively reduced the cross-section of the stud, making it weaker and less able to hold tension on the head gasket.
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The head gasket itself is steel, so having plain water in there has probably rusted it. After it rusts a while, sometimes chunks of it start wandering around and plugging up passages.
Interestingly, you can check ALL of this stuff by taking the heads off. I suspect you didn’t want to hear that.
David,
I wouldn’t be too negative. I’m not sure that the engine would be wrecked.
You could reverse flush and hope for the best. What’s the worst that could happen?
The studs are probably weakened. Head gasket might be toast. And there will be a pile of crud in the sides of the block where the coolant sits. The water pump may or may not leak. But it will depend upon the static water level. In one block I looked at, there was a distinct “dirty bath mark” about one third of the way up the water pump, so maybe only the lowest sections of the head gasket were “wet”, if that.
But the block and heads will be fine. Pistons, rings, bearings, valves, tappets etc shouldn’t be effected. Liners might be ugly, but I can’t see them being a problem.
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I don’t think you need to worry. I’ve just got the heads off my Double Six which hasn’t ran for 30 years and musn’t have had proper antifreeze solution as the expansion tank was completely rotted out.
The heads will come off if you take your time (see my thread in V12 section) and once everything is cleaned up you’ll know what’s what. The block is unlikely to be damaged as it’s alloy and has no faces which would rot. The heads could be rotted in the ‘triangles’ round each stud but that doesn’t mean the rest of engine is scrap. The studs will be corroded. You can buy a new set for around £200.
If your intentions are just to get the car running you’ve not really got much to lose as if it’s no good you can then strip it down.
Even if the studs are corroded you wan’t snap them by running the car. I snapped 3 of mine and it takes a lot of force on a long bar to do it
engine which hasn’t run since 1986 and probably had no antifreeze in it
things don’t look so bad when you start cleaning them
studs could be badly corroded but it takes a lot of force to shear them
even with bad corrosion on water-jacket studs the thread which enters the block can be in perfect condition
Thankfully, it never gets that cold where I live.
I wanted to hear the truth, whatever it may be. After I asked the question, I recalled watching a program called ‘Coltrains, Plains, and Automobiles’ hosted by Robbie Coltrain. In it, he visits a German aircraft restorer who found a WW2 plane that’d been in a lake in Belgium for 40 years and the engine was in very good condition. Fingers crossed.
The thing is, the corrosion inhibitors in antifreeze get used up. That’s why you’re supposed to change it every 2 years, and why long-life coolant with a 5 year life was an advance. So for periods of decades, it doesn’t make much difference whether they left coolant in, or water.
Snapping the studs is not usually the concern. The problem is that the amount of tension degrades with corrosion. When the head nuts were originally torqued, that torque spec applied a designed amount of compression on the head gasket. As the studs corrode, the cross section diminishes, and the compression on the head gasket is gradually diminished. Not good.
Easy to fix, though. Simply retorque all the head nuts. Just do them one at a time; remove the nut, clean up the threads, apply anti-seize to the threads and sealant to both sides of the washer if it’s a 7/16" nut, replace the thin flat washers with 1/8" thick washers under the outboard 3/8" nuts, and reinstall and retorque to spec. If a stud is too corroded, you’ll know it, because you won’t be able to achieve the spec torque; either the stud will snap or it’ll just start yielding, you just keep turning the nut and the torque doesn’t rise any more. New studs time.