Engine Flush Effectiveness Comparison

[campbeam]

I have been using diesel to flush my engine when doing oil changes for many, many years. For the past 2 years, I have done about 12 oil changes to desludge my Toyota 2006 Aurion engine. In that time, I have not used a commercial product. After a few false starts, I think that the engine is finally sludge free. However, a few recent posts got me thinking about whether my engine could be still badly sludged and it was time to change over to a commercial product. Penrite engine flush is currently on special at Autobarn [25% discount] so that is the product I used for this comparison effectiveness test.

I cleaned the oil filter cartridge and housing of any sludge particles, dropped the used engine oil [about 1 month old] then did an engine flush with 6 litres of diesel.

Following photo shows the results. Cleaned the oil filter cartridge and housing of any sludge particles, dropped the diesel then filled with new oil and performed the Penrite engine flush.

What I did notice was while the engine was running during the Penrite engine flush, the engine was idling a lower revs approx. 600 instead of the usual 700. Guess this is the effect of the oil being thinned during the treatment. After photo does show sludge particles and the oil was not too badly contaminated.

Overall quite happy with these results for my 2006 Aurion engine. I will say that I am encouraged to possibly include the Penrite engine flush in my maintenance schedule.

I have a 2008 Aurion as my project car so thinking about doing a future comparison doing a Penrite engine flush first then the diesel flush as a follow up.

 

 

 

[campbeam]

16 hours ago, campbeam said:

I have a 2008 Aurion as my project car so thinking about doing a future comparison doing a Penrite engine flush first then the diesel flush as a follow up.

Not raIning yet, so I did a follow up comparison adding the Penrite engine flush to the used engine oil after the engine had been warmed up and idling for at least 10 minutes. As expected, the oil was quite a dark colour after the flush and has been discarded. I then did the diesel engine flush and also idled the warmed up engine or at least 10 minutes. Surprisingly, there were slightly more sludge particles for the diesel flush than the Penrite flush [highly similar to the previously posted photos] .

Only conclusion, I am prepared to draw at this stage is that a 2nd engine flush does produce results.

[campbeam]

I have noticed a few posts on the internet expressing an opinion that commercial flush is essentially kerosene with additives so I decided to attempt a follow up comparison between Penrite engine flush and kerosene. Previous weekend, I idled the engine on my 2008 Prodigy for at least 2 hours. This was new engine oil with the penrite flush that had only been previously used for about 10 minutes.

Before starting the kerosene flush comparison, I checked the oil filter cartridge and determined that the amount of sludge particles was quite nominal. I then added approx. 375 ml of kerosene to the engine oil and idled the cold engine for 5 minutes. A visual check of the oil did not indicate any change. I then decided to run the engine until it was warm then an additional 10 minutes [similar to instructions for the Penrite Flush.

Afterwards, I checked the oil filter cartridge and also dropped the oil. There was no noticable change in the amount of sludge particles and the oil colour. At this stage, the apparent visual comparison results are quite inconclusive [in my opinion].

Now planning to continue to warm the engine and idle it for an additional 10 minutes for the next few weekends and see if there are any obvious changes worth mentioning..

[campbeam]

Convenient for comparison purposes to look at a past photo to see the quantity of sludge particles. "Sludgy" has certainly deserved her name.

More than 3 years later, I am certain [again] that the engine is getting to be sludge free. 

I will have to remember to get another photo when I next drop the engine oil.

As a follow up, I did not include the Penrite Engine Flush in future oil changes but changed to using a double flush with diesel as per this thread.

I am also using a full synthetic engine oil prefering those with more detergent additives.