It's YOUR car, do whatever you want to do with it. Just make sure when you sell it, you tell the buyer what you did to it. Be honest.... NOT CALLING YOU DISHONEST.....
There's people that dumps leak seals to close up head gaskets and sell to unsuspecting buyers. If everyone was honest, the used car market would be dead.
No it wouldn't, it would be better. When I shopped for a used car, I always asked the people to tell me what's wrong with the car. When they said "nothing", I knew they were lying! When I asked WHY are they selling it then, they always stubbled for an answer. 99% of the time I passed. I also tell them I work on cars so I can fix it myself. sometimes they would tell me, mostly they wouldn't.