Ever since (some time before) I got my crown vic, the oil dipstick tube has been rusted through near the bracket that secures it to the head (you could see light looking down the tube). I recently realized how big this hole was, and after two years of sometimes thinking “I should fix that” I decided to fix that.
There are two major downsides to having a gaping hole in your dipstick tube as I see it. The first is the obvious - contaminants are easily able to get into the oil, including bits of rust from the tube itself. Also with where this is located, any time I drive through a puddle, heavy rain, etc, it’s likely that water would make its way into the oil thanks to the tire.
The other problem as I see it, is that this hole essentially creates a vacuum leak. Being a fuel-injected car with a MAF, the only air that should come in through the PCV is air which has already been metered and enters the engine through (the opposite side) breather tube, which comes from the intake runner. This hole allows air to enter the crankcase and go through the PCV and into the engine unmetered - essentially, acting as a small vacuum leak.
But that’s enough rambling - picture time. Here’s a picture from before I patched it up (after I cleaned the oil from the area with the help of brake cleaner and a lot of elbow grease) - the wooden handle of a foam brush fit perfectly (it was a 2” foam brush from walmart, less than a dollar) in the hole to keep cleaner and crap from going in the oil. It also showcases the hole since the light wood contrasts the rust:
You can see why I wanted to patch this gaping hole. Not only does it present the contamination issues mentioned above in addition to defeating the whole “positive” of “positive crankcase ventilation,” it also spews oil vapor and makes this side of the engine bay continually dirtier than the other.
Here you can see it patched up with steelstik, a putty made by JB weld with some pretty good reviews - yes it was done in two parts (I got the first, upper patch on, took a picture since I have no idea where my inspection mirror went, and realized I missed part of the hole) but it seems to be bonding well. I’m going to give it overnight to cure (nowhere I have to go this evening) and we’ll see how it holds up:
So there’s that. I felt like sharing this since little things like this are amongst my favorite things to find on Oppo - and maybe some of you are the same way.