Phantom oil leak...

[choke artist]

So, I've got an '83 720 that runs like a champ and has low miles...but the thing drips oil. Every time I park, I have a small puddle of oil under my truck. Thought it was the oil pan gasket so I replaced that....still dripping.

 

Today I sprayed the engine degreaser on 'er and tried to isolate the source, it's hard to tell with all the crap in the way but it looks like it's coming from behind (or in the vicinity) of the motor mount just next to the oil filter. I'm fairly certain it's not from the filter, it was leaking before and I've sinced replaced the filter. This truck would be perfect if not for this and it's driving me batty. Any thoughts?

[wayno]

Check the oil senser, do you have the gauges in the center console, or just the oil light?

It would be just in back of the oilfilter, just above the rear side of the motor mount.

If you have the gauges, there would be a big senser beside the oilfilter with two wires going to the end, if you have just the oil light, then it is much smaller with one wire.

It is very difficult to see in this area, when looking for the leak, I would suggest buying brakeclean, or a high quality spray degreaser, spray a lot around that area, blow off the area with air, let dry, then start it up and do whatever you can to see in the areas, use a small mirror, or buy a small one on a telescoping handle with an ajustable end, and use a good bright flashlight.

Clean everything in the area, around the oilfliter, check the valve cover also.

See the gold senser behind the oilfilter with the rubber cover and yellow wires on the end of it.

[metalmonkey47]

Wayno, looks like yours leaks too ^^^ lol

 

 

 

OP, are you sure your drip is from the motor and not transmission?

[datzenmike]

If near the oil filter that's a long way forward from the transmission. Oil tends 'gravitate' downwards and backwards from the fan blowing air and the forward motion of the vehicle. I had my old 620 alt and mount on that side wet with oil and it was the timing cover seal behind the crank pulley. Yes, I have had leaky oil senders.

 

choke artist, if you have the sender in wayno's picture be sure to use the correct wrench when tightening/removing that oil sender. Slip it down between the sender and the block. I believe it's a non metric 9/16 or 5/8. If you don't have an oil gauge then remove the wire and fit a socket.

[Laecaon]

Yes oil sender can be leaky, I needed a new wrench to change mine, then I did it in Home Depots parking lot. If it is near the tranny, I had a problem with my rear main seal. Didnt seem to leak when running (checked while parked over shop floor), but as soon as I turned the car off a giant puddle developed.

[datzenmike]

This could be because the PCV would cause a slightly low or negative pressure in the crank case. Outside air would be trying to get it while running.

[wayno]

Everything leaked on that engine, it had a lot, i mean a LOT of blowby, I was putting almost an oilchange a week in that truck/engine at the time, if I filled the tank, and filled up the oil, and then went on a trip, i would use about 3 quarts per tank, but when I parked the truck, it would only leave minimal oil spots, but it did leave spots, I am not saying it didn't leak.

 

Wayno, looks like yours leaks too ^^^ lol

 

 

 

OP, are you sure your drip is from the motor and not transmission?

[banzai510(hainz)]

Mine, was the stock oil sender diaphram

[Rustina 510]

Did you make sure the oil filter mount was cleaned? I had a oil filter that leaked and replaced it, but forgot to clean the area that the filter touches the motor, it had crusty burned rubber and didn't seal. Clean it and see of that does the trik