the-glove
Jr. Member
Help! I'm an idiot and overfilled my engine oil by probably about 2 quarts. I have a 67 with a 1988 Mustang 5.0 SEFI in it. Been having trouble getting accurate read on dipstick because the power brake booster is in the way. Long story short, thought I was really low on oil and added in 2 3/4 quarts while in an autoparts parking lot. When I started the engine, saw a little bit of smoke coming out of the right side of the engine.....seemed to be from under where the headers are.....it died down after a bit. Not sure if this was related to overfilling. Looked at the dipstick again and this time it was way over the top notch.
Instead of immediately draining out some oil, like an idiot I tried driving home. Seemed to drive fine on the road and freeway for about 10 mins. However, when I hit an uphill section, stopped for a stop sign on the hill, then hit the gas.....the engine started sputtering almost as if running out of gas. I let go of the gas and let it idle, which evened it out after a bit, then tried again. After doing this a couple of times, was able to gain some forward momentum which made the engine run smoother again. However, this kept happening the rest of the way home on any uphill sections. If I hit the gas after slowing down or at a stop sign, the engine would sputter and I'd have to let it idle. Pretty much, I had to get momentum going until rpm's were higher and then it would run fine. Ran fine on level ground and downhill and as long as I was able to keep rpm's up.
I let it sit for a few days, then drained out 2 quarts of oil. Next time I started it, it started and idled fine. Ran fine going downhill (and for some reason also when I reversed uphill about 5 feet), until I tried turning around halfway down and going back up the hill. Started sputtering again. I had to back into a level area, then get about 20 feet of run-up to get rpm's and speed up then it went fine up the hill. Seems to go uphill fine as long as I don't stop.
So I'm guessing by overfilling the oil, the oil got whipped up and frothy by camshaft and oil started going where it shouldn't. So what should I do now? Should draining out the 2 quarts have fixed it (my best guess is that is how much I overfilled by)? Or does it sound like there's still too much oil in there, so the engine is sloshing through too much oil, and the added strain of uphills makes the engine lose power....but if rpm's are high enough it can work through that? Does it sound like there's oil in the combustion chamber? Should I just try running it for a while to hope that the oil gets worked out of wherever it got forced into? I'm really hoping I didn't do permanent damage to the engine. If there's damage, why would it idle ok and run fine on level ground? Thanks.
Instead of immediately draining out some oil, like an idiot I tried driving home. Seemed to drive fine on the road and freeway for about 10 mins. However, when I hit an uphill section, stopped for a stop sign on the hill, then hit the gas.....the engine started sputtering almost as if running out of gas. I let go of the gas and let it idle, which evened it out after a bit, then tried again. After doing this a couple of times, was able to gain some forward momentum which made the engine run smoother again. However, this kept happening the rest of the way home on any uphill sections. If I hit the gas after slowing down or at a stop sign, the engine would sputter and I'd have to let it idle. Pretty much, I had to get momentum going until rpm's were higher and then it would run fine. Ran fine on level ground and downhill and as long as I was able to keep rpm's up.
I let it sit for a few days, then drained out 2 quarts of oil. Next time I started it, it started and idled fine. Ran fine going downhill (and for some reason also when I reversed uphill about 5 feet), until I tried turning around halfway down and going back up the hill. Started sputtering again. I had to back into a level area, then get about 20 feet of run-up to get rpm's and speed up then it went fine up the hill. Seems to go uphill fine as long as I don't stop.
So I'm guessing by overfilling the oil, the oil got whipped up and frothy by camshaft and oil started going where it shouldn't. So what should I do now? Should draining out the 2 quarts have fixed it (my best guess is that is how much I overfilled by)? Or does it sound like there's still too much oil in there, so the engine is sloshing through too much oil, and the added strain of uphills makes the engine lose power....but if rpm's are high enough it can work through that? Does it sound like there's oil in the combustion chamber? Should I just try running it for a while to hope that the oil gets worked out of wherever it got forced into? I'm really hoping I didn't do permanent damage to the engine. If there's damage, why would it idle ok and run fine on level ground? Thanks.
