Shariff
New Member
Hi I have VP D2 55 engine, I was thinking to use an engine flush fluid mixed with old engine oil. Has any have any recommendations, experience any issues. Would it do any harm to the engine.
yes it will make the engine sound like a bag of spanners do not do it!
Drain the old oil with the engine hot, after running, preferably under power, for half an hour. That will be just as effective as a low-viscosity flushing oil with no risk to bearings and other components. Adding Wynn's Engine Flush or something similar beforehand is cheap enough, £5.99 at one website, but I cannot see it achieving anything that a standard drain will not.
I know this has rather been done-to-death over the years, but there is absolutely no reason why an engine which has been properly serviced with modern oil and filters would have any crud which could get past the filter and block any oilways. Using flushing oil in such an engine is a waste of time and money.
I have removed sumps from many engines over the years and one or two of those were from engines which had not been serviced properly (or at all!). It's not very common these days because oils are so much better and synthetic oils virtually immune, but those mis-treated engines had a layer of thick sludge several mm thick lining the bottom of the sump.
This thick goo, the consistency of raw window putty, is mainly mineral oil which has broken down into carbon through burning. I do not believe that flushing oil would shift this sludge and, even if it did, I definitely would not want that stuff being "re-dissolved" and circulated around my engine. The only safe way to solve such a build-up is to remove the sump.
On every properly serviced engine I have stripped in the last 20 years the sump (and engine innards generally) has merely shown the metal to be stained brown which is not a problem. Even the brown staining can be avoided if synthetic oil has been used .... but that's a different thread!
Richard