How do you know when your motor is dirty or clean?

Messages
230
Location
Front Range, Colorado
I can tell when the wife's Camry need decarboning and when I had low compression in one cylinder of my Land Cruiser but how do you know when your motor need to be cleaned and how do you know when its done being cleaned? I have Seafoamed via the carb/PCV several different vehicles and have had different amounts of smoke from each one. I assume if you keep Seafoaming over and over it will stop smoking??? Right? What parts in the motor get fouled other than the valves, rings and piston? But when you add to the oil MMO, AutoRX, Seafoam, ect how do you know when it done being cleaned without removing valve cover or oil pan? I bought an abused Land Cruiser with major buildup under the valve cover. Oil Crud buildup More Crud These pic were after one OCI. I did not take pic of the buildup when I first got the vehicle. It had stalagmites on the valve adjusting bolt/nuts. Now how can one say its needs "X" amount of treatments or "X" amount of miles to clear this up? I also had a Chevy 350 with a dead cylinder. It was full of the same crud that was under the Land Cruiser valve cover. Over time I got that cylinder to clean out and work again but it took a long time. Once again, there can be no "X" amount of time to clear it up. My present Land Cruiser has 364,000 mi on it. It has a golden varnish on under the valve cover. Golden Glaze This could take longer or shorter time to remove as its baked on. I could not remove it with my hand unlike the other Land Cruiser build up pic where I could just wipe it off. Other then taking the motor apart is it a guessing game to know when your motor is clean?
 
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Messages
2,500
Location
Dallas, Texas
I believed you have answered your own question. "How do you know when you engine needs to be cleaned without taking off the valve covers?" The easy reply is "You don't." There are probably a few hundreds of thousands of cars out there that have had a lifetime of 15,000 mile OCI's with minimal air filter changes. I've seen too many people who think an oil change is a "treat" for their car. I know in my Taurus, Xterra, and F150 it is a bear to get anything but a tiny view of the valve train through the fill hole. The '02 Taurus has some sort of steel baffle over the valve train under the fill hole, so in order to get a view you really need some type of small mirror to look around in there. The F150 is kind of high off the ground and much like the Xterra has a longer fill neck, so there again you need some type of mirror. As far as pulling the valve covers the Taurus is the only one that pulling one side of the valve covers wouldn't be a full day job. Perhaps I could do it to the F-150's driver side without too much of an issue, but why? The valve covers don't leak and with 2 jobs I don't have much time. If you have owned a car since new, and have done regular oil changes at a decent interval you won't need any mechanics in a bottle. However, every car I have ever owned has been used. My wife is the first person I have known to be around my age and pay for a New new car herself, (and when we were dating she would act like her car would self destruct if she didn't get an oil change before it rolled over every 3,000 miles.) So my bet is that it is Clean, but again, the time to pull valve covers... There are exceptions, like with Saturn's that have sticky rings due to design flaws. Or in my Taurus's case I have a leaky timing chain cover. The Taurus loses about 1 quart every 1,500 miles or so, drips onto the exterior of the catalytic coverter so at least I don't leave a puddle behind. It is a bear to get to and to fix, so I have just switched to topping off with 15w40 and 10w40 weight oils (depending on the season). I have run MMO and Auto RX through it, those didn't help the leak. I think they cleaned it more so that it ran smoother and dripped more freely. When it was 107 degrees out I tried some Lubro Moly Engine Oil Saver and it did seem to significantly slow things down. But topping a 30 weight HM oil change off with Engine Oil Saver, and 40 weight oil, during colder weather that should be coming, sounds like a bad mix. Just sticking with 10w40 for now, thinking about going to 10w40 HM, but that is a different thread. Am I absolutely certain that I could have open heart surgery off of my engine after it has been torn down into its components? No. But then again, my 3.0 Vulcan Single Overhead Cam engine could probably run off of a mixture of Crisco and Vaseline (especially when it is 107 degrees out there). Would it run further, farther, and with more vitality when I put the pedal to the metal if I pulled everything off the engine and fixed the leak so that I could run the back spec 5w20 engine oil? Perhaps. Although the 3 day weekend, or the small fortune needed to fix such a thing is not on the horizon, and paying for it 1 quart of oil at a time is easier. Is it clean because of my normal topping off? I'd bet so. Cheapo 15w40, Supertech or otherwise is nothing to poo poo on. Not sure if I would start using 15w40 or any other Mechanic in a bottle/ flush in another used car I bought. I would probably go for a few quick OCI's that are right off a long highway drive and hot to help get some built up crud out of the engine. I find that going slow (multiple short OCI's) and removing sludge/varnish, even at the price of a few OEM PCV valves, is better than going fast and the chance of losing an engine. When buying used I would always recommend a quick OCI interval to get things started.
 
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