Fixing an Oil Leaking Bronco - Where to Begin

[bostonbronconut]

I've recently had a lot of help figuring out a solution for an oil leak coming between the back of my intake manifold and engine block. It looks like I'll be pulling the manifold off and installing some new gaskets. Unfortunately, that doesn't seem to be the only source of oil leaking from my engine bay. As of recently, I've noticed more oil leaking from under the hood and it is hard to pinpoint where it is coming from. The majority of the puddling seems to be happening from the driver-side of the engine bay. There is so much grime and dirt that it isn't easy enough to just find a few drops of oil and go from there.

So, here I am, once again, asking for your help and patience as I try to figure out how to stop dispersing 5W-30 around my town. Where should I begin? Are there hoses I should be looking at for replacement? Is it potentially the header covers and they need a new gasket?

I've attached some bad photos; my plan is to get the Bronco on some stands so I can really get under there. I can provide as much info/photos if requested. As always, thank you for your help in resolving this.

 

[DirtDonk]

Well, I might as well be the first to say it. Because if you don't know, WE sure don't know!
But first of all, to help you and the rest of us to diagnose, you really, really, really must clean it up. Is that not an easy chore where you are? Big mess perhaps?
It's pretty much unavoidable with all that oil all over the vehicle. For all we know it's just one leak that has been blowing all over the place for years making all the mess. I've seen valve cover leaks do that and worse.
More likely than not though, with any vehicle this old you're leaking from pretty much every orifice there is.
But you're going to have to clean it up first.

This cleanup does two things. First it lets you more easily (if that's an appropriate word here!) pinpoint the leak(s). Second, and possibly more importantly, the cleaner components let you actually work on stopping the leaks WITHOUT introducing some of this gunk to the inside where it can actually do harm.
You don't want to pull the manifold off if you're going to have to worry about dropping chunks of gunk into the crankcase through the lifter valley/gallery.
Leaving anything dirty while you work on it is just not a good practice. Sure, pro mechanics have to do it all the time because they're on the clock. But you can't be on the clock because you have to clean the work area first.

Bottom line, is that stuff has been there too long for us to give any good reference points of interest.
We could literally go down the list of possible culprits, and it might end up being only one, or literally all of them.
Oil pan rail, oil pan dipstick, transmission top cover and front shaft seal and rear output seal, transfer case seal(s), engine rear main seal, valve cover(s), cylinder head, front/timing cover, distributor shaft, PCV valve, PCV return grommet and fitting, air cleaner housing buildup, front main seal, thermostat housing, power steering (if applicable), front differential, steering stabilizer, overflow grease from the steering and suspension components. All of the above...
See what I mean about many possible sources?

Good luck.
(but good luck starts with a good cleaning!)

Paul

 

[Glass Pony]

I can hear my father telling me this 50 years ago.
" You have to get under there and clean and scape and then clean some more".
Some of the points of interest on the driver's side that I could think of would be:
Valve cover gasket
Dipstick housing entering oil pan
oil pan gasket
oil pressure sensor
Power steering system (if you have it)

 

[DirtDonk]

haha! Beat 'ya by a few seconds!

 

[Lawndart]

Do I see auto-tranny lines? If so, I am betting power steering as well.
That area is indicative of a power steering reservoir or line leak. Mine started leaving a nice little puddle about a week ago and the "oil" on the driver's side frame rail and there back. One hose in the power steering system had a small leak near the end. I sniped it off and re-installed; leak gone. Err, leak gone for now.

 

[DirtDonk]

Oh yeah. Another spot is where the fuel pump bolts to the engine. And yet another one (a big one!) is the oil pressure sending unit where it is screwed into the extension tube and engine near the oil filter.
And speaking of the filter... That's another potential culprit if it was not installed correctly. When done properly, they rarely leak unless they just sat around for twenty years or so.
But we don't know any Broncos that ever sit that long. Right? (insert your favorite rolling eyes or disbelief emoji here)

 

[Oldtimer]

I would start at a quarter (25¢) car wash, with a whole lot of quarters.
Check local auto detail shops, they may have (or know of) an engine steam cleaner.

 

[bostonbronconut]

Good call on the self-service car wash. It is amazing how much I was able to get off. I am sure I still have some cleaning ahead with a long brush but it is a big start. Hopefully, I'll start to see a drip and can narrow down where some of the leaks are coming from. I still might replace a lot of gaskets/parts just so I don't have to deal with it in the future. It is better to do it right and fix it for a while than just throwing on a bandaid/duct tape.

 

[Beau Nugget]

If you can get access to a hot water pressure washer you can clean that up very quickly. Hot water pressure cuts through old oil and dirt so much faster than cold water, it’s no comparison.