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Cleaning out an engine

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Old 06-14-2017, 02:24 PM
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vanster
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Default Cleaning out an engine

The oil in this 22yr old engine reeks of varnish, fuel and mold. What is the best way to clean out the old. My thought is to drain the oil, refill with cheap oil, drain and repeat before refilling with the good stuff. The TB appears to be Ok for a few miles and the cam gears don't look worn.
Old 06-14-2017, 02:41 PM
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davek9
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what year please, may want to do some type of a Trans fluid mix, run up to temp and dump it, then the hi detergent oil and run a few miles and dump again?
Old 06-14-2017, 03:35 PM
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Adamant1971
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Originally Posted by davek9
what year please, may want to do some type of a Trans fluid mix, run up to temp and dump it, then the hi detergent oil and run a few miles and dump again?
+928 start with a mix of ATF, it will clean everything.

The rotary engine guys use ATF in the intake as well to clean the combustion chamber.
Old 06-14-2017, 03:56 PM
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crushingday
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What sort of oil/ATF, and what kind of ATF should be used when doing this? I have have a '78 and am considering doing this.
Old 06-14-2017, 04:30 PM
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skpyle
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Originally Posted by crushingday
What sort of oil/ATF, and what kind of ATF should be used when doing this? I have have a '78 and am considering doing this.
I believe any El-Cheapo Dexron III will work just fine.
Old 06-14-2017, 05:10 PM
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GT6ixer
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^^^Yeah, cheap oil. Don't make my mistake. Non-runner for 10+ years. Filled with VR1. Flooded while trying to start. Oil mixed with gas, so changed oil after 100 miles with VR1 again. Then drove it up to Colin for some work including new engine mounts and he suggested a WYAIT oil pan gasket change. Ugggh, so that's 16 qts of good stuff down the drain in less than 500 miles.
Old 06-14-2017, 05:27 PM
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vanster
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It's this 81 5sp that I picked up. It's going to be a bigger challenge than I was bargaining for.
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Old 06-14-2017, 05:45 PM
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vanster
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Do I really need to drop the fuel tank or can I just drain it and replace all the filters?
Old 06-14-2017, 06:56 PM
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Dropping the tank is the only way you'll be able to clean it out effectively. My car's tank sat half the time your's did and the inside was coated with a thick film of old gas. If you don't clean it out I suspect over time the new gas you put in will break that crud down and eventually ruin the fuel pump, clog the fuel filter and probably eventually clog the injectors.

Dropping the tank isn't very difficult, just takes time. Dwayne's write up is what I followed.

You are probably gonna need a new fuel sender as well. Check out what mine looked like when I removed it.

https://rennlist.com/forums/928-foru...l#post13483935
Old 06-14-2017, 07:01 PM
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AirtekHVAC
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I think you need to use rislone, or swepco mixed with cheap oil to clean it out. (The engine, not the tank)

Last edited by AirtekHVAC; 06-14-2017 at 10:09 PM.
Old 06-14-2017, 07:26 PM
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vanster
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Thanks Nate
Great info...why am I saving this car again?
Old 06-14-2017, 07:30 PM
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skpyle
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Originally Posted by vanster
Thanks Nate
Great info...why am I saving this car again?

Because you can.
Old 06-14-2017, 10:08 PM
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AirtekHVAC
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You can always send it to me.....I like basket cases.....
Old 06-14-2017, 10:44 PM
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dr bob
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My oil recommendation:

-- Don't flush with any oil you wouldn't normally use in the car.

-- Some oil passages and galleys may have restrictions caused by crud. Listen carefully for noises.

-- A couple quarts of reasonable ATF in the oil is a good idea for loosening old oil deposits. The ATF is a very high detergent oil equivalent to maybe 5 - 10 wt motor oil in viscosity. So no hard loading on the engine with this mix in it.

---

Were it mine...

Knowing that the TB and water pump are immediate needs, I'd start by cleaning the outside of the engine as one would for the major front of the engine service. While all that stuff is off, put in your favorite blend of engine cleaning chems, and circulate it through using a drill motor powering the oil pump directly. Rotate the crank periodically by hand, ditto the cams. Whatever you put in needs to lubricate the oil pump so probably not a good idea to just put in straight cleaning solvent, but you get the idea. You can drain and refill a few times until the stuff you take out looks OK. Then put in a few quarts of cheap oil, just enough to pump through and get your cleaning brew pushed out. Drain that after you finish the TB/WP service, put in your favorite oil flavor for normal use and you'll be good to go. Following this protocol allows you to be more aggressive with the cleaning steps without worrying about lubrication while you flush. If MM/OPG is in your immediate future, of course you'll have easy access to the bottom end to see your results. Else use a borescope of other inspection cam to look at your results. It's an easy look at the bottom of the sump through the oil pipe port on the front shelf.
Old 06-14-2017, 11:40 PM
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vanster
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Good suggestions and it makes total sense. What is the best way to clean and engine bay and the outside of the engine itself with ending up with water in the cylinders?


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