I always thought it was better to drain old oil when it was at operating temp. Reason is that more of it came out faster and sludge came out too.

 

I have been changing oil in vehicles for a very long time now. My dad was a master mechanic way before I was born and did a lot of mechanic work for friends and other folks at home. I was always out there with him trying to help but was mostly I the way.

Changing oil was something he figured I could handle so he let me do it. I was probably 8 or 9 the first time he had me slide under a car to drain the oil.

In the old days it was a fairly common practice to put a quart of transmission oil in your engine and drive around for a half hour or so before draining and changing the oil.

A can of ATF was cheap enough and thin enough that it would do a fair job of washing the sludge out of your engine.

Most cars would be down at least a little by the time the owner decided it might be time to actually change it anyway.

The old timey oil seemed to create a lot more sludge in a lot less time too.

Although I never forgot the drain plug, filter, or new oil I know a lot of so called mechanics that have. One of the other guys that worked at the Texaco station I worked at when I was in high school was always forgetting to put the drain plug back in.

The Texaco station had a hose hooked up to a 55 gallon oil drum with the new oil in it and a pump that would fill the car up. You could set a lever on the pump for more or less oil, it depended on how much oil the engine was supposed to take but most cars were 5 quarts. You just stuck the hose in the oil fill hole in the engine and turned the pump on. After 5 quarts the pump shut off. Of course if you had not put the drain plug back in that oil was on the shop floor instead of in the engine.

Some times he would forget that he had already put the new oil in and would turn the pump on and put 5 more quarts in. that was not quite as messy as just running it on the floor but took more time because you had to drain the oil and do it all over again. Of course once he drained the oil on an over fill like that he dumped it in the drain oil barrel.

The boss finally fired him after like the 5th time of doing that.

Another fellow that worked at the Ford garage in town forgot to put the filter on the car several times. One time the owner was in such a rush that as soon as the car came off the lift he took off with it. Ruined the engine on that one.

Seemed like a lot of the guys at the Ford garage did not tighten the drain plug because they replaced several engines because the plug had fallen out and the oil drained while the owners were driving.

I learned to make sure that there were no leaks by starting the engine and looking under the car. I always fretted that I didn't have the drain plug tight enough so I started torquing them instead of just hand tightening them with a wrench.

 

No, not a hand pump. As I stated:

 

I use a Mityvac 4300 fluid evacuator on my HHR. Makes oil changes a breeze. I also use one in our shop as I do most of the maintenance on our equipment (turbo diesel John Deere tractor, Bobcat, etc). I also use the 4300 for brake fluid changes/ flushing and trans fluid changes.

 

I just read this thread. My best story involved my then-19-year-old brother and his '77 Cutlass. He changed the oil in my Dad's condo parking lot (not allowed, but we were fast, and I was playing lookout).

He thought he was done, so he fired it up. It turns out he had the filter for the Chevy 350 and not the Olds 350. The filters were the same size, but the gasket diameters were NOT. His car had headers on it, too, so he was revving it a bit, when he suddenly saw the "river of Pennzoil" as we still call it 30 years later and a cloud of smoke. The poor kid freaked out, but at least he shut it down. By the time I saw it, I was laughing hard. It turned out OK, but the smoke from the exhaust was just the ultimate. The imagery still makes me laugh. We were no longer "sneaky"...

The moral? Take your time, and make sure you check your work AND your parts...

 

I don't think he meant "cold" down, just don't burn your forearm cool.

I usually at least warm it up then drain it. If you have enough sludge to be worried about it, you have much larger problems.

 

So I changed the oil on my lawnmower yesterday (not the first time doing it) and I made an even bigger mess than I did with the car. I also burnt the mess out of my finger.

Needless to say I think I'm going to stay away from anything that needs an oil change for a while. Oh well rub some dirt on it and move on.

 

I guess "mechanicing" just isn't your thing.

Last week I did my Spring maintenance on my equipment. Changed oil in 4 lawnmowers, Kubota tractor, pressure washer and a generator.
Lubed all and sharpened all blades.
No injuries and not 1 spill.

 

I've always figured the job just ain't done if I don't bleed on it at least a little.

 

My girlfriend has had the worst luck with the fast oil change shops.

The first time she had an issue was when the "tech" pulled the transmission plug instead of the oil plug (he had to drop the skid plate to get to the tranny plug).

The next time they stripped the threads on the plug hole in the aluminum oil pan and didn't tell her. They stuck in a self tapping bolt that leaked.

On another visit, they changed her center stop light bulb and overtightened the screws on the lens, cracking it. A week later she gets pulled over because lens fell off.

Then there was the time the "tech" opened the radiator cap without stopping to let it vent and sprayed her with hot coolant.

I guess that's why I like to do my own stunts...