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I have a 1986 F-150 5.0 EFI. It just developed a nice sized oil leak and I am trying to find out where it is coming from.
Here is some background. When the truck was last inspected in May the garage that I go to (whom I trust) said that I needed some engine mounts since mine were shot. There was also some antifreeze leaking near the water pump. When working on that I had the timing chain replaced (original from 1986) because it was still functional but on its last legs. The last thing they did was replace the timing chain cover.
The truck has been running like a champ lately.
On Saturday I drove it I could occasionally smell something burning while I was driving. Not all the time but when stopped at a red light it was pronounced. I figured that there was a leak. I got the truck to a parking lot at Advance Auto Parts and could see the oil dripping on the ground will the truck was running. I ran in and got a quart and put it in and then drove the 20 miles home. In my driveway I parked it while running got out and could see the oil dripping. I parked it in my garage that has an oil change pit. Later when the truck was cool I pulled the dip stick and it was full. All through the week I did not drive it and cleaned out all the oil underneath.
I bought some UV oil to add to the crankcase and I have a UV light. Today I turned on the truck and let it sit for 10 minutes. No leak emerged. So then I drove it for a couple of miles and could smell the burning at the stop signs but it was running great. Back home the leak appeared only now the oil was everywhere under the passenger side of the truck - not the drivers side. Using the UV light I looked at the upper cylinder covers - no UV oil glow. The oil seems to be all under and around the alternator and the front passenger side of the truck. I have inserted some photos and tried to get some with the UV light on the area.
If the new seal on the new timing chain cover gave out would this cause and oil leak? It seems to me that this is the area where the leak is but frankly it is hard to tell exactly.
I take the truck to the shop tomorrow but I wanted some opinions so that I can share them with the garage. Any help is appreciated. I am in my oil pit looking up at the front of the oil pan and timing chain area. As you can see this is where the oil is coming from. No oil on the other side of the engine.
Same view but a little closer with the UV light on it.
I think the problem I had was due to not getting the bottom of the timing cover perfectly flush with the bottom of the engine block. With the oil pan gasket spliced to reinstall the timing cover, this created a perfect place for a leak. I think the timing chain slings oil right at that spot, too.
If you still have leakage from that area, I recommend replacing the spliced stock cork gasket with a one-piece aftermarket style. Access stinks, but once done the gasket should outlast you:
Usually on a high mileage truck the front seal wears a groove into the harmonic balancer. Did they spell out all the parts they used and is there a repair sleeve in the parts list? Another pesky place to leak is around the large bolt that holds the balancer onto the front of the crankshaft. Oil will make it's way past the keyway on the crankshaft, and migrate around the large washer and bolt, and get slung all over the place. The factory put sealer in this area to stop it, but it's often forgotten.
Both of these problems can be checked and fixed by simply pulling the balancer back off without pulling the timing cover back off.
