I took this pic months ago while doing my valve adjustment, I'm really concerned if pouring one bottle of engine oil flush can clean these dark stains above the rocker arm cover!



the engine is at ~80k miles
I bought it from its first owner with 70k and the service book shows several mineral oils have been used in the past (I used synthetic from day one)
does engine flush harm the engine more than it can benefit it?

 

Run a can of Sea Foam with your engine oil for the next few oil changes should clean that up nicely.

 

Thank you for your reply,
Any alternatives to Seafoam are you aware of?
because it's not easy to get where I live

 

Sorry I cannot comment on other products. I have solely used that product because of how well it cleans metal parts and engine components.

 

Sea Foam is a widely used product with a good reputation (as far as I know), but I have one question: Should one be concerned about the product's effects on non-metal parts? I'm thinking of seals, gaskets, etc. Does the product come with any warnings? I'm asking out of my own curiosity. Thanks.

 

There are folks who put some in their oil, some in their gas, and then what's left they get drawn into the intake manifold using engine vacuum. So I'm thinking it's pretty friendly to most materials.

I've never used it though.

 

Stick with safe products if you use anything at all. The goop dissolves in hot oil if it's churned up enough, so it won't clog your oil pump.

Don't sweat it. Increase frequency of your oil changes, clean out your pcv valve.

 

Looks like previous owner might have extended oil changes. I would attempt seafoam and go from there. If top end looks like that. Oil pick up might be like that as well

 

Its fine for seals, gaskets 100% safe for gas engines. Only warning on the bottle is not for human consumption and is combustible.