Best Method for Piston Soak?

[explorer2030]

Hello All,

I wanted to share a piston soak procedure from Hyundai service bulletin 21-EM-003H that I found interesting. After adding 2 ounces of cleaning solution into the cylinder, they have you pressurize it to 30 psi for 3 minutes using a leakdown test tool to force the cleaning solution into all of the piston ring lands. To further agitate the cleaning solution you then connect a hose between specific cylinders and crank the engine 3 times for 3 seconds. Note that they say this can be done every 36,000 miles as part of routine maintenance. While I probably wouldn't do the agitation step, I think adding a pressurization step to a standard piston soak would make it much more effective. I am interested to hear everyone's thoughts, especially anyone that has tried something similar on their vehicle.

 

[YZJB]

That is fascinating and seems very thorough. Interesting!

 

[BMWTurboDzl]

Hello All,

I wanted to share a piston soak procedure from Hyundai service bulletin 21-EM-003H that I found interesting. After adding 2 ounces of cleaning solution into the cylinder, they have you pressurize it to 30 psi for 3 minutes using a leakdown test tool to force the cleaning solution into all of the piston ring lands. To further agitate the cleaning solution you then connect a hose between specific cylinders and crank the engine 3 times for 3 seconds. Note that they say this can be done every 36,000 miles as part of routine maintenance. While I probably wouldn't do the agitation step, I think adding a pressurization step to a standard piston soak would make it much more effective. I am interested to hear everyone's thoughts, especially anyone that has tried something similar on their vehicle.

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Seems like a lot of work for an issue which could be remedied by running a different oil (ex, Valvoline R&P).

 

[Donald]

I wonder if the Hyundai piston soak is targeted for a loss of compression (first two rings gunked up with crud) or excessive oil use (oil control ring gunked up with crud)?

 

[Kira]

Or both.

 

[explorer2030]

Seems like a lot of work for an issue which could be remedied by running a different oil (ex, Valvoline R&P).

I have been following the new Valvoline R&P oil as information comes out, but I think it's too early to say whether or not it lives up to its claims. Even if it proves to be moderately effective for cleaning around the piston rings and skirt, I don't see how it would fully replace a piston soak for removing carbon buildup on the piston crowns where there isn't continuous oil flow. The other downside is that the R&P oil could take up to 3+ years to see substantial results depending on your oil change interval.

 

[BMWTurboDzl]

I have been following the new Valvoline R&P oil as information comes out, but I think it's too early to say whether or not it lives up to its claims. Even if it proves to be moderately effective for cleaning around the piston rings and skirt, I don't see how it would fully replace a piston soak for removing carbon buildup on the piston crowns where there isn't continuous oil flow. The other downside is that the R&P oil could take up to 3+ years to see substantial results depending on your oil change interval.

Or it could take 3 oil changes to observe improvements. It's essentially a no cost solution.