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Old 01-26-2018, 08:03 PM   #1
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Totally agree. However, while motor oil may kill the cats, the only way to know will be to run them and cook the oil out with exhaust heat. I don't know the condition of the exhaust manifold to head bolts, but at this point I wouldn't risk breaking a few just to see if there is oil in there when we all know the answer to that one (see post 38). If the cats fail deal with it then. They may be fine. Lots of failed AOS that oil soaked cats came back from.
The US SE has 4 cats. 2 in the headers and 2 before the muffler. One problem i see is back pressure. Oil / water mixture in cats can be very tough / doughy (don't know the right english word). If you want to start the car, this can cause more problems than a sheared off head bolt. Also if the oil starts to burn (specially the header cats) by exhaust temperature, the cats will clog / die in a short time.

There are specialized companies that can clean oil contaminated catalytic converters. Oil contamination happens often if turbochargers fail.

And yes, if one or more header bolt shears off this is also a problem. But if you soak them in rust dessolver (min. 2-3 days and don't start the engine in this time) and clean them extensively (best is to soak and clean more than one time) with a steel brush before you try to open them in general they don't shear off. In my opinion these shear off fails are often caused by much too short preparation time.

My approach is always to check for risks and try to go the way with the least risks. Even if it takes more time. And for shure everybody has made it's own experiences and has it's own opinion. In the end everything can go wrong, even if you have tried to take all aspects in consideration.

Just my 2 cents…

Regards, Markus

Last edited by Smallblock454; 01-26-2018 at 08:16 PM.
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Old 01-26-2018, 08:31 PM   #2
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I'm not sure this is a good idea. Just a rich fuel mixture causes the cats to overheat and burn out.
I was thinking of flushing them out long before actually running the engine. The Jet Fuel would all be evaporated out (and blown through with compressed air when I flushed) Do you think that would still be a problem?

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...And yes, if one or more header bolt shears off this is also a problem. But if you soak them in rust dessolver (min. 2-3 days and don't start the engine in this time) ...
On the first day, I sprayed them with penetrating oil, and I have done it again a few times. There is still risk, but I think I can remove them safely if needed.

The rear cats and muffler are already unbolted. I am going to replace them with a good, dry parts before I start. The 'wet' muffler from this car will become my spare.
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Old 01-27-2018, 08:48 AM   #3
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[QUOTE=78F350;561197]I was thinking of flushing them out long before actually running the engine. The Jet Fuel would all be evaporated out (and blown through with compressed air when I flushed) Do you think that would still be a problem?


I would not recommend using ANY hydrocarbon in the cats. To the cats the only real difference between gasoline and jet fuel is the length of the molecular chain. JP5, JP8 doesn't matter, they are similar to diesel which does not completely evaporate and will leave residual hydrocarbons in the cats (feels oily) which is mostly paraffin. Simple Green maybe?

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Old 01-27-2018, 10:17 AM   #4
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I would not recommend using ANY hydrocarbon in the cats. To the cats the only real difference between gasoline and jet fuel is the length of the molecular chain. ...
Sometimes I'm slow, but it is finally sinking in. No flammable hydrocarbons. Now tending towards soapy water to get the oily film out of the primary cats, rather than just running the car and burning it out.
I saw some YouTube videos about cleaning old cats. People who were trying to fix failed cats didn't have good results. In this case, I assume they are still good, but coated with oil.
Eric the Car Guy: https://www.youtube.com/watch?v=1uukKrgBXeo
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Old 01-27-2018, 12:15 PM   #5
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I'm just going to throw this out there as something to consider. I can tell by what you've already accomplished that you have no reservations to getting your hands dirty.
I question how "oily" the cats can be. Let's think about the sequence of events and how oil came to be in the cats in the first place.
Flood waters rise and enter the muffler. water fills the entire exhaust system and enters a couple cylinders, (intake valves are at top), then displaces oil to the TOP of the crankcase and back out through the cylinders. Because the exhaust system is entirely full and due to phase separation (oil floating on top of the water) then the only contact of oil to the cats is at the top of the substrate as the oil migrates out the exhaust in a thin stream at the surface of the water. What does this mean? It is likely there was only a minor stream of oil in the exhaust at any given time, far less than the flood that would be seen from a failed AOS that experienced hydrolock. The water/oil did not form an emulsion since it was never sheared. Certainly cleaning is not going to hurt anything but is it necessary?
Regardless I am enjoying this thread. Keep up the good work!

The point of this post is: in my experience with flooded boat engines is that the quicker you could get one running (usually hours) the better. Detailing can happen later.

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Old 01-27-2018, 10:51 PM   #6
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I'm just going to throw this out there as something to consider. I can tell by what you've already accomplished that you have no reservations to getting your hands dirty.
I question how "oily" the cats can be. Let's think about the sequence of events and how oil came to be in the cats in the first place.
Flood waters rise and enter the muffler. water fills the entire exhaust system and enters a couple cylinders, (intake valves are at top), then displaces oil to the TOP of the crankcase and back out through the cylinders. Because the exhaust system is entirely full and due to phase separation (oil floating on top of the water) then the only contact of oil to the cats is at the top of the substrate as the oil migrates out the exhaust in a thin stream at the surface of the water. What does this mean? It is likely there was only a minor stream of oil in the exhaust at any given time, far less than the flood that would be seen from a failed AOS that experienced hydrolock. The water/oil did not form an emulsion since it was never sheared. Certainly cleaning is not going to hurt anything but is it necessary?
Regardless I am enjoying this thread. Keep up the good work!

The point of this post is: in my experience with flooded boat engines is that the quicker you could get one running (usually hours) the better. Detailing can happen later.
I think you've made some good points here. Let's think about in detail. What options do we have when the car was flooded and what damage can be caused. I try to keep it short.

Materials:
Engine casing: alloy. Pistons: steel. Oil control rings: steel (can rust). Piston rings: steel (can rust). In general some carbon resedue, because it's a used engine. Catalytic converter housing: stainless steel. Catalytic converter: ceramics, and materials that start the redox reaction above around 500° C / 932° F.

Time:
Car did sit für 4 months and was flodded with sweet water. Sweet water is a plus, because salt water would have been much more agressive. But the not stainless steel / not alloy parts can be corroded a bit. Will it make a difference if it sits 2 days or 4 months? I would say yes. Will it make a difference if it sits 4 months and 2 weeks. I would say no. Also the conditions in which it sat might make a difference.

Debree:
Was the water conatminated with sand or debree? If yes that seems intake wise to be stopped by the air intake filter. In that case Exhaust wise sand / debree can have found it's way into the combustion chamber. Water could also pass oil control rings and piston ring gaps and get into engine housing. Very small debree might sit in between them or passed. That would be a minus, because of the alloy block. (I suspect in sweet water rivers / lakes you have cleaner water (OK maybe not in harbors)). Will water have solved the carbon inside the combustion chamber in 4 weeks? Probably not.

Parameters we / i don't know:
Was the engine running and hot, when the poor car was flooded. Was the engine stopped by flooded water coming in the intake system. And would that make a difference?

How was the car saved? For example: if the front was lifted while saving it initially, this would be a plus, because fluids could run out of the exhaust system. But we don't know that.

Oily cats and what kind of oil/water consistency might we find there:
If the engine was flooded while running i suspect the redox reaction in the cats was stopped before the oil was flushed into them. So i suspect they were "cold".
Could there be an oil/water mixture caused while the engine running? Hm, to me that seems to be improbable.
Could be oil / water be sucked back into the engine if the header / exhaust systen is connected to the engine while starting for the first time? I would say no, but Honestly not shure about that. If the car was raised in the front, most of the liquid will be come out of the exhaust system. And because 78F350 said the muffler is off the car now i would say fluids have had their change to drain away the exhaust system.

So i think 911monty is right on that. Kind of hydrolocking will be not possible. Headers don't need to be removed, but i think it's a good idea to remove the muffler and lift the front of the car before starting it.

Grand childen:
Seems to have a very good influence. Videos have sound tracks now.

All fingers crossed!

Regards, Markus
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Old 01-28-2018, 07:02 PM   #7
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Not much progress today, as it should be. A little break is good. Tomorrow should be a busy day working on the car.
Installing the coils:
https://youtu.be/HfNgOWQjFEY
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