i heard by alot of OLD mechanic put half a quart of gas on the oil every oil change for about 3 or 4 oil changes will help get ride of sludge in the engine. i laugh everytime i hear it but is that true?
Greetings,
* I would not mix any fuel / or fuel additive in with engine oil on a modern vehicle, too dangerous...
Haven't heard of using gasoline, but using clear highway-grade diesel fuel, and there is a specific procedure to do this - you need to follow the -exact- procedure, or you risk burning bearings in the motor.
In any case, if the engine is sludged as badly as the videos that Dave posted, even that procedure won't "magically" cure the problem - the motor needs to cleaned / oil passages & ports need to be inspected, cleaned and/or components replaced, just like the tech. did in the video.
* When we got our 1997 ford Aspire, it was badly sludged (not as bad as the motor in the video, but still a real mess), due to the former owner running it for many months with a stuck-open thermostat: it took me -days- to get the top & bottom ends cleaned up. (It would have been a $1,200+ job, just for labor hrs., if a shop did the work.)
This is some interesting info. I found when doing the rehab on the Aspire:
If the motor does not get up to normal operating temp, it will not burn off any accumulated condensation (water) in the motor: water in the oil is a primary cause for oil sludging. If the oil is further neglected / not changed, the additive pack will degrade to nothing -> then the motor is in real trouble, it will sludge up / oil will 'carbonize' quickly.
Same issue occurs on "church goer / grocery getter" vehicles: if the motor is only used a short time continuously -> never reaches normal operating temperature, the oil never has a chance to boil off any accumulated condensation, sludge forms.
Replacing a thermostat that is stuck-open, or regularly warming the vehicle up to operating temp., even if taking a short-trip ride are the best things you can do to prevent sludge from forming in the engine.. And regular oil changes w/ good quality oil, of course.
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Some things the video did not show that I ended up doing:
Label the cam caps, make a picture diagram when uninstalling (or take photos), and re-install in the same order. Same w/ any lifters, etc. that are removed.
After cleaning the cams / caps / lifters, I soaked everything in fresh oil that I pre-heated, overnight, before re-installing.
The Aspire has a 'real' EGR valve, that was totally plugged up, needed cleaning. The accumulated mass of sludge on the EGR ports was the consistency of 'tar', it was a mess.
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I've had good luck using Marvell Mystery Oil w/ short-interval oil & filter changes to help "clean out" a motor that has been neglected:
16oz. of Mystery Oil added to the balance of new oil / new filter change, and running for (750 / 1,000) mile interval helps to dislodge/dissolve minor sludging, and the product is mild enough not to significantly change the viscosity of the oil: I personally have found it safe to use.
Good videos Dave, those brought back some fond memories...
I think I'm gonna change the oil in the Aspire now. :lol:
Regards,
GottaCruise