I have my engine out of my 2005 Prius. The intake and exhaust ports are open and I can see oil/carbon build up (engine has 100k miles). Is there a cleaner that is safe to use while I have easy access, or better just to leave it alone?
You can get pretty aggressive because its solid metal... You could even polish it up to a mirror like shine so everything flows faster even if it doesn't. Main concept being is mass produced vehicles are built as quickly and inexpensively as possible, so there's hundreds of ways to upgrade a vehicle... One of those ways is turning all that black carbon in your pics into bright shiny mirror-like polished metal even if it doesn't... In other words I'm talking about the time honored tradition of porting&polishing: What Is Cylinder Head Porting, And How Does It Increase Horsepower? Also a good summary of porting vs. polishing as well as all the best tools to use:
You could probably use B-12 Chemtool. It's essentially toluene and acetone. It won't hurt the metal and it's meant to go through the engine anyway.
Well, yes... It does limit what is safe to do, but there's so many different ways to port and polish... Some would be ideal in this case, some would not be wise.
1. I am wondering what causes the engine to be out of the car. 2. I would limit the cleaning to applying solvent on a cloth and using that to scrub - unless the OP is going to remove the head from the block.
Yes, to Patrick's point about wondering why your have the engine out in the first place? If I went to all the trouble of pulling an engine it would make sense to pull the head and do a thorough inspection and cleaning/boost performance of ports because it's really not that much additional work compared to pulling the engine itself...
If you want to do it right pull the head and send it to a speed shop and they’ll hot tank it and deck it. Btw what kind of oil has this engine seen it’s whole life?
