Hi,

I own a 97 ford ranger and I'd like to remove some sludge, gum and varnish from my engine by adding a valve cleaner product in my oil reservoir before changing oil.

Does this product would be harmful for any seal or something similar ?
Any reasons why I shouldn't do this, please tell me.

Thank you folks.

 

I've disassembled a few engines that have been well used (and a lot of small engines that have been run hot!) and haven't found much sludge or gum or varnish in any of them. Main place of deposits are the valves which an in tank fuel additive might help.