Cleaning oil out of cooling system?

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Got the "new" engine in the Grand Maruis. It ran terrible! Turns out 20 year old intake manifold gaskets are not reusable despite what yahoos on the Internet say.

Put new I/M gaskets in and fired it up. Full of coolant , belt, etc. It ran for 15 or so minutes and got up to 225 before I killed it. I felt the thermostat not opening. Pulled off the hose and found ...
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Well that's not ideal. That's oil. It plugged the passages to the temp sensor for the gauge cluster so that wasn't working but I had an OBDII scanner hooked up and was able to read the cylinder head temp that way.

I think I've ruled out a bad head gasket - no coolant in oil. I vaccumed out the paste, flushed everything and refilled again. Ran it for a while and the thermostat did open, gauge worked and with the AC running on a 95 degree day it never got about 197 - which is exactly where a 195 degree thermostat should run. It didn't over heat or start pushing a weird frothy mixture out of the radiator cap like my 5.4 did.

When I got this engine there was some residual oil in the coolant passages. I replaced the oil filter housing gasket and tried to clean it out but may have been bad.

Unfortunately I had the heater core hooked up for that first run. So now I need to try to clean that up so it doesn't plug. And flush out the rest of the system to get the oil out.

Anyone have any suggestions? Dish powder? What should I use?
 
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+2 on dish powder, a few teaspoons will do you, and frequent water change outs.

The stuff is bleach, so it's not good to have in there long term.

Also inspect all your rubber hoses for oil sweat-through. Went through this with a saturn cylinder head. You'll know-- the rubber will smear on your skin and feel all gooey.

Call me paranoid, but when I do a motor swap or major work I refill with plain water to make sure there aren't any mega leaks, then drain and refill with 100% coolant to make 50/50.
 

SwampSurvivor

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+2 on dish powder, a few teaspoons will do you, and frequent water change outs.

The stuff is bleach, so it's not good to have in there long term.

Also inspect all your rubber hoses for oil sweat-through. Went through this with a saturn cylinder head. You'll know-- the rubber will smear on your skin and feel all gooey.

Call me paranoid, but when I do a motor swap or major work I refill with plain water to make sure there aren't any mega leaks, then drain and refill with 100% coolant to make 50/50.

I actually did that haha. Filled it with 3 gallons of distilled water then drained to see what came out. Nothing bad. Then once I put in the coolant this happend.

The hoses are brand new so they should be able to tolerate it once. I'll get a small thing of dish powder and run it through with a flush and fill kit or something.

Now it has tap water. We're not able to leave the house for a few days because of ... reasons ... and I ran out of distilled water.
 
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If you do use citric acid, don't overdo it on the concentration. I've seen it attack brass transmission coolers in the radiator side tank to the point of leaking.
Automatic dishwasher detergent, either liquid or powder would be my choice, followed by a couple clear water flushes.
 
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Had the transmission cooler dump into the radiator of a Chevy Spark. After replacing the radiator, ran half a box of Cascade powder dish washing detergent dissolved in water for 20 minutes with the thermostat out followed by a few rinses. Finish up with this Prestone cleaner which may be hard to find. Remember replace all hoses in contact with the oil.

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Nick1994

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I'd worry after all this is said and done, about it plugging up your radiator passages. Keep a close eye in the time going forward on cooling ability. Might need a radiator replacementl
 
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I would suggest flushing out the system with water from a running hose until it runs as relatively clean. At this point, drain the radiator and add a gallon of Simple Green Extreme Simple Green Aircraft & Precision Cleaner and just enough water to fill the degas bottle/overflow tank a quarter of the way. Allow the engine to idle for 30 minutes with the radiator cap off and the heater running.

Once you hit the 30 minute mark, drain the radiator, pull out the thermostat and thoroughly flush and back flush the entire system with a running hose until it runs perfectly clear.

At this point, dissolve 1 lb of citric acid powder in ~1.5 gallons of water and pour the solution in to the cooling system through the thermostat housing and top off with water until full. Put the thermostat back in along with the radiator cap and start the engine. Run it at approximately 2,500 RPM for 15 minutes, and occasionally blip the throttle.

After it cools a bit, drain the radiator, pull the thermostat and flush/back flush until clear and repeat the process of running the engine at 2,500 rpm.

This should help clean everything out before you put coolant back in.
 

SwampSurvivor

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As well as the oil may swell the rubber seals that seal the tanks to the core.
I'd worry after all this is said and done, about it plugging up your radiator passages. Keep a close eye in the time going forward on cooling ability. Might need a radiator replacementl

Radiators are easy to replace - and on a 21 year old vehicle, it really wouldn't be surprising if I had to. I'm only worried about the heater core!

But my 5.4 blew the oil cooler in a similar fashion 5 years ago. It ran longer (enough that it ran itself out of oil) and I haven't had any issues with the hoses or radiator in that time.
 
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Big clue I had problems was no heater in the Michigan winter on my VW Passat. Found the heater core was all plugged up. Had NOT added the correct coolant for the top up. Result was formation of a gooey plug. Added some white vinegar, ran the engine for a few minutes, then attached a garden hose with duct tape to one of the coolant hose at the clamp. After about 15 mins on full tap pressure was able clear out the blockage.

My local repair shop told me I needed a new heater core, so this fix saved me a ton of money. Always pays to second guess the "experts"!
 

SwampSurvivor

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Big clue I had problems was no heater in the Michigan winter on my VW Passat. Found the heater core was all plugged up. Had NOT added the correct coolant for the top up. Result was formation of a gooey plug. Added some white vinegar, ran the engine for a few minutes, then attached a garden hose with duct tape to one of the coolant hose at the clamp. After about 15 mins on full tap pressure was able clear out the blockage.

My local repair shop told me I needed a new heater core, so this fix saved me a ton of money. Always pays to second guess the "experts"!

I'm really hoping to save the heater core on this one. It had nuclear heat last winter, hoping it will still have nuclear heat this winter. I really don't want to run too much through it so I'm going to leave the heater core bypassed while I flush the rest of the cooling system. I bought some extra lengths of heater hose, once this is done I should be able to use the prestone flush n fill kit to backflush the heatercore
 
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