Your (un)favorite "I can laugh about it now, but at the time....." moment(s) - PeachParts Mercedes-Benz Forum

pdrayton · #1 08-13-2007, 06:04 PM

Everyone has them (I hope). I had one a week ago. You know those moments when everything seems to suddenly stop and a rush of cognition about how stupid you've been floods into your brain and you want to either run and hide or get a strong drink.

But since I'm sure (hoping like hell) I'm not the only shadetree who's done some stupid stuff, I figured we could all get a laugh and some experience out of each others mistakes.

So here's the stupid thing I did that I can laugh about now but at the time I was just dumbfounded about how stupid I was, and how I had missed the little signs along the way that something was wrong.

My 240D runs on WVO blend so I have a flat plate heat exchanger in the engine bay. This, plus the fact that vege oil is much more viscous than diesel, especially when cold, means that the stock lift pump has to work really hard to get enough oil to the IP. Not good for the IP, so an auxiliary fuel pump is put near the fuel tank to push the viscous oil to the IP at the front.

Well, I was quite proud of myself for installing an aux fuel pump. And I felt so much less antsy about cold starts - after all I had 5-9 psi of fuel pressure to the lift pump. Until I discovered (while fixing an unrelated fuel supply issue) my stupidity.

I had the fuel lines connected the wrong way. I had connected the output of the fuel pump to the return line at the front of the car. So the fuel pump I had proudly installed was busily pumping against the lift pump and the IP. Sheez! When I found that out I couldn't believe it. What a dumb donkey!

Needless to say I felt like a complete dork since I had been driving around feeling all secure and safe for about a year because I had an aux fuel pump. Yes, I had an aux fuel pump, but it was doing the opposite of what I thought it was! I don't know how the car drove like that - 5-9psi up the return line?

What did I learn?

I learned not to make assumptions about the fuel lines at the front of the car. I thought the top metal fuel line must be the supply. Don't know why I thought that, but it seemed very logical at the time.

I'm now wondering if the return line was actually bypassing the 2ndary fuel filter and supplying the IP with fuel the whole time?

Anyway the car's fuel problems are solved, and I'm a wise man now.

How about you?

pdrayton · #2 08-14-2007, 07:23 AM

Ahh geez Margy, it is just me.

bustedbenz · #3 08-14-2007, 12:11 PM

It's not related to the Mercedes but my most famous "it seemed like a good idea at the time" moment was a few (ok, more like eight or ten) years ago when they gave me my first multimeter for Christmas, it was a pretty nice Extech 460 or 463 or something like that, it's not with me at the moment... anyway, I was just playing with it, I knew how to set it to ohms and test my tongue to see if it still had low resistance the way it did five seconds ago, that kind of thing... and I knew that I could check the voltage of a wall outlet by setting it to ac volts.

But... I asked myself.... how many AMPS does that outlet have? :-D

I didn't realize that the time that amperage was a current drain measurement and not just a static "at rest" measurement - so I dutifully plugged in a power strip (so I could reach it easier or something) and set the meter to amps, plugged the positive lead into the amp socket, and stuck it in.

Pffffffttt.... needless to say, it shorted out the power strip... the circuit breaker on the strip saved the rest of that outlet and so forth I guess... but it melted the tip of the + lead on my tester, and fried the power strip... yeah, explaining THAT one to my dad was a lot of fun

Dubyagee · #4 08-14-2007, 12:21 PM

I "forgot" the crank damper bolt once. It didn't forget me though.

Palangi · #5 08-14-2007, 04:34 PM

Quote:

Originally Posted by bustedbenz

But... I asked myself.... how many AMPS does that outlet have? :-D

Many years ago in a high school electronics class, there was this one kid who really didn't belong in that class. We decided to have a little fun with him...., we talked him in to checking how many milliamps came out of the wall outlet.

As we were heading for the door, we heard a big KaPOW!!! The sound of a brand new Simpson 260 meter blowing up.

Simpson 260 was $50 in those days. Your tax dollars well spent.

E320wagon'94 · #6 08-14-2007, 04:55 PM

I took off my A/C compressor, not realizing that the front bolts seal of the block. My mom took the car to the grocery stor, and said it was smoking from under the hood, I went to look under the hood and saw oil had been sprayed all over the place byt the belts/fan. It was all over the fenderwells, and the underside of the hood (which I had just spent 4 hours scraping and painting). Theres still oil stains on the black underside of the hood, and the baby blue fenderwells stain pretty easlily, so after a good degreasing i still have a nice reminder of my amateurity.
-Zach

winmutt · #7 08-14-2007, 05:19 PM

I failed to depressurize the fuels system on my first car, 85 200SX. Failed to wear appropriate eye wear. Failed to look away when pulling the fuel line off the fuel filter.

Running around a busy parking lot stark raving mad screaming at the top of my lungs? Priceless.

LUVMBDiesels · #8 08-14-2007, 05:24 PM

A friend and I were redoing the kitchen in a town house I had bought. We THOUGHT we had shut off all the water in the house and started to cut off the old pipes to the faucet. Well lo-and-behold, it turned out that that line still had pressure in it. The pipe came off with a BANG and the water came gushing, no streaming, no erupting out of the 1/2 inch pipe. The basement was flooded instantly as I ran outside to shut off the main line (inside a pipe well about 4 feet underground) Well the cover of this well was never put on right and it was full of rainwater. I grabbed the valve and had the handle come off in my hand! Running back inside I saw my friend trying in vain to hold a rag on the end of the pipe. I grabbed a pair of pliers and went out and finally shut off the water. Both of us were soaked and miserable. We then had to finish the job we started and get the water back on.

Now this was at 2am and remember what I said about it being a town house? The next door neighbors had just come home from a day out horseback riding and the wife was in the shower all soapy when all of a sudden the water went off! It turns out that the main supplied both houses.

Next day they mentioned the water going off at 2am and I had to say "really? it did?"

tankdriver · #9 08-14-2007, 05:54 PM

I have no difficult car things that I can laugh about now. They still make me mad. I'm still angry at the gasket on the water pump I missed, requiring me to do the job 3 times. F'n invisible gasket.

Mine's related to a sculpture/table I made. The tabletop is made of steel conveyor belt pieces (see the who likes art thread in OD for pic). I glued them all down, and needed to fill the space in between them. I tried just painting in black, but that didn't work. Then I tried Bondo and resurfaced the pieces so the bondo was just in the cracks and used a permanent marker, but that looked like s***. As I'm tediously scraping out the bondo, it occurs to me that this is basically the purpose of grout. So the 15 min grout job I ended up with took me three days.

JazzArtDesign · #10 08-14-2007, 05:54 PM

Not MB related either, (and I hope this doesn't happen with my new Benz)

I drove my old ford ranger about 300 miles with a blown head gasket. That was smart. Ended up Cracking the head and costing about 2000 dollars to replace.

dawsonj3 · #11 08-14-2007, 06:28 PM

Well, here's the dumbest thing I've ever done:

I was going to cook steaks on the grill one evening, so I went outside to check the charcoal supply. As I casually reached into the bag (without looking), I became aware of an intense burning sensation - which I discovered was due to the dozen or so hornets stinging my hand. It turns out that there was a nest. I was pretty fired up after this, so I rationally decided I would grab my air rifle and blast the hell out of the charcoal bag and teach the little bastards a lesson. Unbeknownst to me, there was a full can of silver spray paint behind the bag, which, once punctured, spun around on the deck surface and sent silver paint everywhere. So, in addition to being in agony from the bee stings, I was able to look forward to cleaning the deck off with paint thinner!

carnut · #12 08-14-2007, 07:36 PM

My best car related embarassing moment happened about 20 years ago. I had just finished restoring a 68 Mustang fastback and had driven it home from the paint shop. Because freshly painted cars seem to be magnetic, attracting other cars, I parked it on the left side of the garage refusing to drive it till "Murphys Law" wore off. About 3 days later while at work, I discovered that my check book was in the Mustang. I drove to the house, pulled up an inclined driveway to the right of my Mustang with my 1937 Oldsmobile street rod. Left it running, hit the garage door opener and flew out of the Olds up to the Mustang opening the right door to get the book from the glove box. While bent over and the right door fully open, I heard my Olds getting louder and louder. Looked over my shoulder and saw the Olds coming up the driveway in drive! The left corner of its bumper hit the door jamb of the Mustang, virtually pinning me in the car! The car was in gear trying to push the Mustang! I climbed over the open door, slid down the Olds' fender and got inside. Then I sloooowly backed up the 37 Olds to clear the car and put it in park and shut it off. The damage: Red paint on the r/rear quarter of the mustang, yellow paint on the L/front fender of the Olds and the only dent was a small dimple in the door latch jamb of the Mustang! The red paint came off with rubbing compound, the Olds fender had to be repainted and the hinges realigned on the Mustang door! 3 inches over to the right, the Olds would have ended up in my kitchen!

Stevo · #13 08-14-2007, 08:26 PM

While assembling a 616 after spending a bunch of money on a rebuild, I installed the little gear that drives the oil pump upside down. No oil pressure

when I pulled the oil pump and looked up the little hole I figured it out. I was getting ready to track down the guilty party and inflect maximum punishment...oh wait

Dieseldoofus · #14 08-14-2007, 09:47 PM

A month ago I replaced my front wheel bearings with nothing but the MB tool kit, a screw driver hammer and allen wrench (makes the job about twice as difficult than using an air gun and a floor jack). After I got everything back together I realized that I hadn't tightened the lock bolts on the spindle nuts.

rrgrassi · #15 08-15-2007, 11:06 AM

YEAH!!! Here is one of the many dumb things...baptism by tranny fluid.

My first car, a '73 Pontiac Grand Prix. 400 cid, THM 400 tranny. I decided to change the tranny fluid and filter. I had my Chilton manual and followed the direction of loosening the pan bolts a bit, then making a "slope" by loosening the rear bolts to almost out with the others in a bit more so that the pan could drop and begin draining. Well the pan did not drop like the manual said it would. It was stuck to the tranny. Well I was under the car and my head was at the lower end of the slope. Took the rubber mallet and a gasket scraper applied between the housing and the pan...next thing I know, I got a tranny fluid hair and face treatment...