Home » What Wrenching Mistakes Have You Had To Go Back And Fix? It’s Wrenching Wednesday!

What Wrenching Mistakes Have You Had To Go Back And Fix? It’s Wrenching Wednesday!

Wrenching Wednesday Ts 111324
ADVERTISEMENT

When we first moved to Maryland, we had to get our cars inspected to register them, and my wife’s GMC Yukon failed for having a leaky steering box. I decided I should just overhaul everything since I was going to be in there installing parts and that way I wouldn’t have to mess with it again later. In went a rebuilt steering box, new pitman arm, idler arm, inner and outer tie rods, and swaybar links. Everything went together fine, the car passed inspection, and we’ve been driving it around with no issues for months.

But my wife has always complained that it had a slight rattle over bumps. I have jacked it up and checked everything out more than once, but I couldn’t find any problems – until today.

Vidframe Min Top
Vidframe Min Bottom

I crawled under the car without jacking it up and discovered both swaybar links were loose. How did I miss this? I didn’t discover the loose links before because when the car is jacked up and the suspension is at full droop, the slack in the loose connections gets taken up, and they stop rattling. I checked the repair manual, and sure enough, you’re supposed to torque down the links with the wheels on the ground. A half-dozen ratchet turns later, and no more rattle.

20241113 111701 Copy

The moral here, I guess, is if at first you don’t succeed, go back and read the instructions.

ADVERTISEMENT

Your turn: what wrenching mistakes have you had to go back and fix?

Share on facebook
Facebook
Share on whatsapp
WhatsApp
Share on twitter
Twitter
Share on linkedin
LinkedIn
Share on reddit
Reddit
Subscribe
Notify of
65 Comments
Inline Feedbacks
View all comments
SCOTT GREEN
SCOTT GREEN
1 minute ago

Rebuilding an aircooled VW engine. The block was stamped with “040”, indicating a .040″ overbore on the main bearings, so I bought and installed bearings with that in mind. Finished building the engine, not noticing the lateral play in the crankshaft. However, I definitely noticed it after firing the engine up. Turned out it was bored .060″ over…had to tear down the whole engine to replace the bearings with the right size.

Commercial Cook
Commercial Cook
2 hours ago

wanted to replace my intermittently working light bulb in the cluster of my 88 e28 bmw.

resulted in not working econo gauge, and broken soldered bulb (yes another bulb) for Drive gear indicator.

and this is like me doing it 3rd time.
it was the worst.

that night i was swearing while asleep my wife said.

GirchyGirchy
GirchyGirchy
7 hours ago

Luckily mine were all caught quickly and did no harm:

  • Changed the oil in my Altima and forgot to put the oil fill cap back on. Started it up the next morning, wondered, “Why does it seem noisier than usual? Has something changed? Oh fuck!” It barely made a mess.
  • Replaced the rebuilt carb on my ’85 Caprice and forgot to reconnect one of the vacuum hoses. Started it up, got a code, read it (OBDI magic!), plugged hose back in.
  • I had changed the ATF and filter in my Mazda3, even got a new trans pan so I wouldn’t have to clean out the old one. Looked down at the old one after I’d put the new one on and spotted the magnet. Motherfucker! All that planning and I still had to clean up the FIPG goop and re-seal it.
JShaawbaru
JShaawbaru
8 hours ago

The shop that I paid $1700 to fix my Saabaru forgot to torque the hub nut after replacing all (most, more accurately) the parts that were destroyed by the failed wheel bearing. It made it the few hundred miles home from West Virginia, but the next time I drove it I could tell something was wrong, and when I took it all apart, that nut came off with no effort. Had to get a new bearing pressed in. Of course the shop didn’t believe me and wouldn’t give me even a partial refund since I didn’t drive it back to them on a failing bearing.
The coil I had just replaced a few months earlier also spontaneously failed at the same time, so I was chasing a misfire and messing with suspension stuff at the same time. At least while firing the parts cannon, I got new spark plugs, wires, and valve cover gaskets done. Now there’s no more smell of oil burning off the exhaust, and none of the spark plugs are swimming in an oil bath.

Last edited 8 hours ago by JShaawbaru
Ford Friday
Ford Friday
8 hours ago

I was replacing glow plugs on the 7.3 Powerstroke in my F250. This involves getting under the valve cover. When I was in there I accidentally disconnected one of the injector plugs. Fired it up and had a check engine light and a bit of a shake. Apparently it wasn’t designed to be a V7. Of course it was the side of the engine that’s under the intake so that needed to all be pulled again.

Another one, I was doing the timing on a 4.6 in my Crown Vic and forgot to put the tone ring on (basically the piece that the crank position sensor reads so the engine can run). I didn’t realize it until one of my friends sent me a video joking about it.

Last one, I had a 1995 Ford F150 with a 5.0 that I could never figure out how to get running. I replaced the injectors, spark plugs, distributor, coil, throttle position sensor, eventually my friends and I figured it was the engine that had fairly weak compression, so I replaced the engine and it still wouldn’t start. It turns out the whole time it was the MAP sensor. Threw a new one in and it fired right up.

Ford Friday
Ford Friday
7 hours ago
Reply to  Ford Friday

Oh, one more I just remembered. I was replacing the door handle on my E36. It was a coupe so extra pain in the ass because the window is slightly down when the door is open (frameless windows are stupid). There’s a pin on one side and a little ring you screw over the lock cylinder on the other side. I could not for the life of get the ring to stay in place. And scratched the shit out of the door in trying to use a screwdriver to seat the ring. Turns out, the new (used) part I got had the ring on there already, so I had to feed it back through the door and take the ring off. It went in perfectly smoothly after that.

Pit-Smoked Clutch
Pit-Smoked Clutch
8 hours ago

I once smoked a transaxle because I damaged an oil seal while doing the clutch and ALL of the oil leaked out. I had reason to believe the gear oil smell was coming from a previous leak’s mess that I was too lazy and hoist-less to clean up. $600 and 2 days to get a junkyard gearbox in.

LostinTransit
LostinTransit
11 hours ago

I didn’t make the mistake, but the shop did and all after I told them 6 times to do it this way.. I was there Last Wed in an effort to find out if a 28mm kuga sway bar would fit a transit connect and it does.. but even after telling the tech to make sure they use Teflon tape on the sway bar and grease the bushing.. they still didn’t do it right and now I have to take the van to a new shop and allow those guys to correct the mistake the other shop made.

Jatco Xtronic CVT
Jatco Xtronic CVT
13 hours ago

Serious time. While I was replacing my catalytic converter, I was reinstalling my exhaust manifold. Turns out I put the gasket where the manifold meets the engine for cylinder 1 on improperly, and so it let air in. Not only did my car run terribly, but it didn’t take long for it to melt my new catalytic converter before I thought to check my work again…

Gabriel Jones
Gabriel Jones
15 hours ago

I had a Honda xr250 as my main transportation for a while in Bolivia. It started to smoke a bit, so I replaced the rings. I was working out of a small shed and it got pretty late when I was starting to put everything together.

I wanted to put the head back on just to keep the dirt out of the expensive bits, so I hand tightened the cylinder bolts and set the “valve cover” over top of everything.

The next morning, I made sure the timing was right, tightened up the top end and took off. I probably rode a good 500 miles before I noticed a small amount of oil on top of the gear box. I looked for a crack and didn’t see one. I didn’t remember leaving the bolts hand tightened until I started to take the cylinder off again while looking for the culprit.

TLDR: Honda XR 250 will still run great even with a slightly mobile cylinder.

Ok_Im_here
Ok_Im_here
16 hours ago

Thought I knew how to replace my brake pads and discs on my Mazda 6 since I’d done it before. I did not. I missed a bolt on the calipers (in terms of properly tightening it–it looked like I had properly installed and tightened it, but I had not). So I do a test drive–all good. I’m driving along later and there’s a clunk when I brake. That’s not good. Then I realize I’ve lost a lot of braking power. At first I think I just need brake fluid because I check and it’s low. Then while messing with it I look at the caliper on one side and it’s just hanging there by the brake line. I was stuck. I limped the car home hazards on VERY slowly on the shoulder. I had to buy an entire new caliper because the bolts had fallen out and lots of other parts were missing and I couldn’t tell what I had lost on the road. At least I was able to return the main parts of the existing caliper. I felt pretty stupid. On the upside, I lost so much brake fluid I basically had bled the whole system, so I got a fluid replacement for my trouble. They’ve been flawless after making sure the bolts catch and are tightened. Go figure.

WarBox
WarBox
19 hours ago

Chewed up the bendix gear on like 3 starters before realizing that the ring gear on my flywheel had nubs instead of teeth anymore.
Like a month after replacing my clutch. :/
(thankfully I learned the trick of disconnect drive shaft, replace each transmission bolt one at a time with a 10″ long one, and just slide the transmission back to do the work!)

Along with Martin, Dutch Gunderson, Lana and Sally Decker
Along with Martin, Dutch Gunderson, Lana and Sally Decker
20 hours ago

While rebuilding the front suspension on my ’17 Pacifica earlier this year, I was using a good-sized hammer to separate the hub from the control arm at the ball joint (I was replacing the control arms and the ball joints – among other things. Being dainty wasn’t necessary). One errant swing of the hammer however and I hit the spring metal boot clamp on the outer joint in such a way that it popped open and couldn’t be closed back up. My first attempt at a HELP style strap clamp ended up with CV grease everywhere. Eventually got a proper replacement strap, and even more eventually I cleaned up all the errant grease. What a mess.

Slow Joe Crow
Slow Joe Crow
20 hours ago

My most embarrassing moment was my first big project in 1988. The initial problem was snapped studs on the exhaust manifold. I couldn’t easily remove it , so this turned into removing the cylinder head. This all went back together, but wouldn’t start. It turned out I got the firing order wrong and this was fixed by rearranging plug wires.

Smoke&Mears
Smoke&Mears
21 hours ago

I’ve done the timing on my Mk4 24v vr6 at least six times, and my mechanic friend has had the motor & transmission out to do it himself. Still something not right.

Mr. Frick
Mr. Frick
1 day ago

Replaced the intake and valve cover gaskets on my 70 AAR. Took my time and meticulously cleaned everything as I went. Cleaned and touched up the paint on the six barrel intake and valve covers. Buttoned everything back up and decided it was late so I would clean up tomorrow. Next day I realized the shop towels I had carefully placed in the valley to protect the lifters and cam were missing.

LMCorvairFan
LMCorvairFan
17 hours ago
Reply to  Mark Tucker

Putting a new cam in my 70 442 Olds. Carefully cleaned everything, scraped and cleaned the gasket surfaces. Lube on cam, new lifters, manifold gaskets, double row timing chain, install timing cover. All done, put the rad back in, hooked up, new thermostat, coolant, fill burp. Drain oil and new filter, put on new air cleaner. All good, crank a few times, check everything … and notice on top of the battery, the oil slinger that fits on the front of the timing chain. Damn, damn, double damn! Not as bad as having to pull off the manifold but up there in annoyances.

Last edited 17 hours ago by LMCorvairFan
Mark Jacob
Mark Jacob
1 day ago

The old classic – didn’t make sure the old filter gasket wasn’t still on the motor when installing a new oil filter. The doubled-up gaskets made quite the fountain of oil in my driveway.

Along with Martin, Dutch Gunderson, Lana and Sally Decker
Along with Martin, Dutch Gunderson, Lana and Sally Decker
20 hours ago
Reply to  Mark Jacob

To his dying day, whenever I saw one of my old bosses – or his son – they would invariably start our conversation with, “Hey! Do you remember that time you said the oil filter was defective? What an idiot!”

Good-naturedly of course.

Jim Zavist
Jim Zavist
1 day ago

Many years ago, on my first new car (’75 Gremlin), I tried to install an aftermarket air conditioner (from Sears!). In my ignorance, when I installed the compressor, I failed to notice that the pully didn’t clear the mounting bracket that came with the kit (so the pulley would not turn). I had to take it to a mechanic to see what I wasn’t seeing.

TXJeepGuy
TXJeepGuy
1 day ago

Biggest one I ever made was not rotating the engine as I tightened down valve springs on a 4.0 head. Almost made my new head a paperweight.

Sklooner
Sklooner
1 day ago

My Volvo 740 I did the timing belt and all went smoothly, when cleaning up I was looking for the old belt and picked up the box, shook it and discovered I had put it in the box. Next day I went to recycle the box and pulled the old belt out to discover a very new belt inside. Good thing it only took about 45 minutes to do the new belt as the bolts weren’t rusty and I remembered most of what I did the day before

Saul Goodman
Saul Goodman
1 day ago
Reply to  Sklooner

You and Frank now have something in common lol

65
0
Would love your thoughts, please comment.x
()
x